Journal articles: 'Biomolecular and medicinal chemistry, n.e.c'

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Jin, Bong-Suk, Won-Kyu Lee, Kwangseog Ahn, Myung Kyu Lee, and Yeon Gyu Yu. "High-Throughput Screening Method of Inhibitors that Block the Interaction between 2 Helical Regions of HIV-1 gp41." Journal of Biomolecular Screening 10, no. 1 (February 2005): 13–19. http://dx.doi.org/10.1177/1087057104269726.

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The HIV-1 envelope glycoprotein transmembrane subunit, gp41, mediates the fusion of viral and target cell membranes. The 2 helical regions in the ectodomain of gp41, the N-helix and the C-helix, form a helical bundle complex that has been suggested as a fusion-active conformation. Previously, an enzyme-linked immunosorbent assay (ELISA) method had been established to measure the interaction of 2 helical regions of gp41. In this study, the ELISA method was modified to apply high-throughput screening (HTS) of an organic compound library. A few compounds had been identified to prevent the interaction between 2 helical regions of gp41, and they were further shown to inhibit the gp41-mediated viral infection. In addition, they specifically quenched the fluorescence of tryptophan in the N-helix region, indicating that these compounds bound to the N-helix rather than the C-helix of gp41. These results suggested that this assay method targeting gp41 could be used for HTS of HIV fusion inhibitors. ( Journal of Biomolecular Screening 2005:13-19)

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Sauermann, Mamatha, Florian Hahne, Christian Schmidt, Meher Majety, Heiko Rosenfelder, Stephanie Bechtel, Wolfgang Huber, Annemarie Poustka, Dorit Arlt, and Stefan Wiemann. "High-Throughput Flow Cytometry–Based Assay to Identify Apoptosis-Inducing Proteins." Journal of Biomolecular Screening 12, no. 4 (March 22, 2007): 510–20. http://dx.doi.org/10.1177/1087057107301271.

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After sequencing the human genome, the challenge ahead is to systematically analyze the functions and disease relation of the proteins encoded. Here the authors describe the application of a flow cytometry—based high-throughput assay to screen for apoptosis-activating proteins in transiently transfected cells. The assay is based on the detection of activated caspase-3 with a specific antibody, in cells overexpressing proteins tagged C- or N-terminally with yellow fluorescent protein. Fluorescence intensities are measured using a flow cytometer integrated with a high-throughput autosampler. The applicability of this screen has been tested in a pilot screen with 200 proteins. The candidate proteins were all verified in an independent microscopy-based nuclear fragmentation assay, finally resulting in the identification of 6 apoptosis inducers. ( Journal of Biomolecular Screening 2007:510-520)

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Todorov, Petar, Stela Georgieva, Desislava Staneva, Petia Peneva, Petar Grozdanov, Ivanka Nikolova, Evgenia Vasileva-Tonkova, and Ivo Grabchev. "Study of Novel Peptides for Antimicrobial Protection in Solution and on Cotton Fabric." Molecules 27, no. 15 (July 26, 2022): 4770. http://dx.doi.org/10.3390/molecules27154770.

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Some new N- and C-modified biomolecular peptide analogues of both VV-hemorphin-5 and VV-hemorphin-7 with varied amino acids (Cys, Glu, His), 1-adamantanecarboxylic acid, and niacin (nicotinic acid) were synthesized by solid-phase peptide synthesis—Fmoc (9-fluorenylmethoxy-carbonyl) chemistry and were characterized in water solutions with different pH using spectroscopic and electrochemical techniques. Basic physicochemical properties related to the elucidation of the peptide structure at physiological pH have been also studied. The results showed that the interaction of peptide compounds with light and electricity preserves the structural and conformational integrity of the compounds in the solutions. Moreover, textile cotton fibers were modified with the new compounds and the binding of the peptides to the surface of the material was proved by FTIR and SEM analysis. Washing the material with an alkaline soap solution did not show a violation of the modified structure of the cotton. Antiviral activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5), the antimicrobial activity against B. cereus and P. aeruginosa used as model bacterial strains and cytotoxic effect of the peptide derivatives and modified cotton textile material has been evaluated. Antimicrobial tests showed promising activity of the newly synthesized compounds against the used Gram-positive and Gram-negative bacteria. The compounds C-V, H-V, AC-V, and AH-V were found slightly more active than NH7C and NCH7. The activity has been retained after the deposition of the compounds on cotton fibers.

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Dams, Géry, Koen Van Acker, Emmanuel Gustin, Inge Vereycken, Lieve Bunkens, Pascale Holemans, Liesbet Smeulders, Reginald Clayton, Asa Ohagen, and Kurt Hertogs. "A Time-Resolved Fluorescence Assay to Identify Small-Molecule Inhibitors of HIV-1 Fusion." Journal of Biomolecular Screening 12, no. 6 (May 21, 2007): 865–74. http://dx.doi.org/10.1177/1087057107304645.

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Fusion of host cell and human immunodeficiency virus type 1 (HIV-1) membranes is mediated by the 2 “heptad-repeat” regions of the viral gp41 protein. The collapse of the C-terminal heptad-repeat regions into the hydrophobic grooves of a coiled-coil formed by the corresponding homotrimeric N-terminal heptad-repeat regions generates a stable 6-helix bundle. This brings viral and cell membranes together for membrane fusion, facilitating viral entry. The authors developed an assay based on soluble peptides derived from the gp41 N-terminal heptad-repeat region (IQN36) as well as from the C-terminal region (C34). Both peptides were labeled with fluorophores, IQN36 with allophycocyanin (APC) and C34 with the lanthanide europium (Eu3+). Formation of the 6-helix bundle brings both fluorophores in close proximity needed for Förster resonance energy transfer (FRET). Compounds that interfere with binding of C34-Eu with IQN36-APC suppress the FRET signal. The assay was validated with various peptides and small molecules, and quenching issues were addressed. Evaluation of a diversified compound collection in a high-throughput screening campaign enabled identification of small molecules with different chemical scaffolds that inhibit this crucial intermediate in the HIV-1 entry process. This study's observations substantiate the expediency of time-resolved FRET-based assays to identify small-molecule inhibitors of protein-protein interactions. ( Journal of Biomolecular Screening 2007:865-874)

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Wang, Zhongyang, Ge Sun, Mrinmay Mandal, Paul Kohl, Juan de Pablo, Shrayesh N. Patel, and Paul F. Nealey. "Role of Water Molecules in Enabling Site Hopping and Vehicular Transport Mechanisms in Polynorbornene-Based Anion Exchange Membrane." ECS Meeting Abstracts MA2022-02, no. 41 (October 9, 2022): 1536. http://dx.doi.org/10.1149/ma2022-02411536mtgabs.

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Role of Water Molecules in Enabling Site Hopping and Vehicular Transport Mechanisms in Polynorbornene-based Anion Exchange Membrane Zhongyang Wang, ⸹ Ge Sun ， ⸹ Mrinmay Mandal, ‡, Paul A. Kohl, ‡, Juan de Pablo, ⸹ Shrayesh N. Patel, ⸹ and Paul F. Nealey ⸹ ‡ School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332-0100, United States ⸹ Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA Ion exchange membranes are at the heart of electrochemical conversion and storage devices such as fuel cells 1, water electrolyzers 2, CO2 electrolyzers 3. redox flow batteries 4, and reverse electrodialysis 5. Anion exchange membrane fuel cells (AEMFCs) have attracted enormous attention as alternatives to replace perfluorinated, sulfonic acid-based proton exchange membrane fuel cells (PEMFCs) 6 because alkaline membrane electrode assemblies (MEAs) composed of anion exchange ionomers (AEIs) and AEMs that allow the use of Ni 7, 8, Fe 9, and Ag 10 based precious-group-metal (PGM) free catalysts in alkaline environments for hydrogen oxidation reactions (HORs) and oxygen reduction reactions (ORRs). However, the lack of understanding of ion transport mechanisms at different hydration levels of an anion exchange membrane hinders the rational design of the MEAs in an AEMFC. Here we investigate site hopping and vehicular transport mechanisms using anion exchange thin films, interdigitated electrodes, and atomistic molecular dynamics simulations. Halide ion (Br-, Cl- and I-) conductivities in polynorbornene-based thin films are measured as a function of temperature and relative humidity using electrochemical impedance spectroscopy. Halide ions show Arrhenius behaviors, and activation energy (Ea) is for the first time used as an indicator for detecting the transition of site hopping and vehicular transport mechanisms. Using atomistic molecular dynamics simulation, we quantitatively demonstrate that the transition of site hopping and vehicular mechanisms is aided by better solvation environments of anions and more percolated water pathways. References Z. Wang, J. Parrondo, C. He, S. Sankarasubramanian and V. Ramani, Nature Energy, 2019, 4, 281-289. S. Z. Oener, M. J. Foster and S. W. Boettcher, Science, 2020, 369, 1099-1103. D. A. Salvatore, C. M. Gabardo, A. Reyes, C. P. O’Brien, S. Holdcroft, P. Pintauro, B. Bahar, M. Hickner, C. Bae, D. Sinton, E. H. Sargent and C. P. Berlinguette, Nature Energy, 2021, 6, 339-348. K. Lin, Q. Chen, M. R. Gerhardt, L. Tong, S. B. Kim, L. Eisenach, A. W. Valle, D. Hardee, R. G. Gordon, M. J. Aziz and M. P. Marshak, Science, 2015, 349, 1529-1532. R. D. Cusick, Y. Kim and B. E. Logan, Science, 2012, 335, 1474-1477. J. Wang, Y. Zhao, B. P. Setzler, S. Rojas-Carbonell, C. Ben Yehuda, A. Amel, M. Page, L. Wang, K. Hu, L. Shi, S. Gottesfeld, B. Xu and Y. Yan, Nature Energy, 2019, 4, 392-398. G. Braesch, Z. Wang, S. Sankarasubramanian, A. G. Oshchepkov, A. Bonnefont, E. R. Savinova, V. Ramani and M. Chatenet, Journal of Materials Chemistry A, 2020, 8, 20543-20552. S. Kabir, K. Lemire, K. Artyushkova, A. Roy, M. Odgaard, D. Schlueter, A. Oshchepkov, A. Bonnefont, E. Savinova, D. C. Sabarirajan, P. Mandal, E. J. Crumlin, Iryna V. Zenyuk, P. Atanassov and A. Serov, Journal of Materials Chemistry A, 2017, 5, 24433-24443. H. Adabi, A. Shakouri, N. Ul Hassan, J. R. Varcoe, B. Zulevi, A. Serov, J. R. Regalbuto and W. E. Mustain, Nature Energy, 2021, 6, 834-843. H. Erikson, A. Sarapuu and K. Tammeveski, ChemElectroChem, 2019, 6, 73-86.

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Frey, Johanna, Sabine Choppin, Françoise Colobert, and Joanna Wencel-Delord. "Towards Atropoenantiopure N–C Axially Chiral Compounds via Stereoselective C–N Bond Formation." CHIMIA International Journal for Chemistry 74, no. 11 (November 25, 2020): 883–89. http://dx.doi.org/10.2533/chimia.2020.883.

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N–C axial chirality, although disregarded for decades, is an interesting type of chirality with appealing applications in medicinal chemistry and agrochemistry. However, atroposelective synthesis of optically pure compounds is extremely challenging and only a limited number of synthetic routes have been designed. In particular, asymmetric N-arylation reactions allowing atroposelective N–C bond forming events remain scarce, although great advances have been achieved recently. In this minireview we summarize the synthetic approaches towards synthesis of N–C axially chiral compounds via stereocontrolled N–C bond forming events. Both organo-catalyzed and metal-catalyzed transformations are described, thus illustrating the diversity and specificity of both strategies.

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Sun, Kai, Fengji Ma, Lulu Liu, Jingjing Sun, Xin Liu, Yachao Wang, Zhiguo Zhang, and Guisheng Zhang. "Iodine-mediated regioselective C–N and C–I bond formation of alkenes." RSC Advances 5, no. 100 (2015): 82492–95. http://dx.doi.org/10.1039/c5ra14407h.

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Iodine mediated intermolecular C–N and C–I bonds formation of alkenes was realized. A series of alkenes could be converted into the aminoiodination products, which are versatile building blocks in organic synthesis and medicinal chemistry.

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Zhang, Ming, Qiuhong Wang, Yiyuan Peng, Zhiyuan Chen, Changfeng Wan, Junmin Chen, Yongli Zhao, Rongli Zhang, and Ai Qin Zhang. "Transition metal-catalyzed sp3 C–H activation and intramolecular C–N coupling to construct nitrogen heterocyclic scaffolds." Chemical Communications 55, no. 87 (2019): 13048–65. http://dx.doi.org/10.1039/c9cc06609h.

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Dar’in, Dmitry, Mikhail Krasavin, Anton V. Budeev, and Grigory Kantin. "Continued Exploration of Trifunctional Alkyl 4-Chloro-2-diazo-3-oxobutanoates: Streamlined Entry into [1,2,3]Triazolo[5,1-c][1,4]benzoxazines and [1,2,3]Triazolo[5,1-c][1,4]benzoxazepines." Synthesis 53, no. 12 (January 8, 2021): 2155–66. http://dx.doi.org/10.1055/a-1348-9031.

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AbstractFurther exploration of the trifunctional character of previously introduced alkyl 4-chloro-2-diazo-3-oxobutanoates in reactions with N-protected substituted o-aminophenols followed by deprotection provided a convenient entry into [1,2,3]triazolo[5,1-c][1,4]benzoxazines, which are of high medicinal importance, as documented in the literature. The same approach applied to N-protected substituted o-(aminomethyl)phenols afforded [1,2,3]triazolo[5,1-c][1,4]benzoxazepines, which are practically unexplored compounds from a medicinal chemistry perspective. The syntheses start with SN2-type alkylation of the phenol. Removal of the protecting group triggers imine formation followed by Wolff 1,2,3-triazole synthesis.

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Cucu (Diaconu), Dumitrela, and Violeta Mangalagiu. "Pyridine-Imidazlolium Salts: Oxidatively Cleavage of N-C Bond via Nitration." Molbank 2019, no. 4 (November 23, 2019): M1095. http://dx.doi.org/10.3390/m1095.

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Azaheterocycles derivatives with pyridine-imidazole skeleton are compounds of great value for medicinal chemistry. We report herein the nitration of 1,1′-(pyridine-2,6-diylbis(methylene))bis{3-[2-(4-nitrophenyl)-2-oxoethyl]-1H-imidazol-3-ium} bromide using a typical mixture of nitric and sulphuric acid. The nitration occur with the oxidative cleavage of N–C bond between imidazolium ring and methylene group.

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McMurray, Lindsay, Thomas M. McGuire, and Rachel L. Howells. "Recent Advances in Photocatalytic Decarboxylative Coupling Reactions in Medicinal Chemistry." Synthesis 52, no. 12 (March 9, 2020): 1719–37. http://dx.doi.org/10.1055/s-0039-1690843.

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This review covers recent advances in decarboxylative photocatalysis applicable to the medicinal chemist. The review is not intended to be exhaustive, but instead is focussed on transformations that could be useful in the synthesis of drug-like compounds in order to highlight the utility of this methodology in the development of new pharmaceutical candidates.1 Introduction2 C–C Bond Formation3 C–N and C–O Bond Formation4 Fluorination and Trifluoromethylation5 Hydrodecarboxylation6 Protein Functionalisation7 Conclusion

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Tian, Lifang, Yahui Wang, Yue Zheng, Xiaoqing Shao, and Velayudham Ramadoss. "Recent Developments in Photochemical and Electrochemical Decarboxylative C(sp3)–N Bond Formation." Synthesis 52, no. 09 (March 2, 2020): 1357–68. http://dx.doi.org/10.1055/s-0039-1690839.

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Considering the important applications of nitrogen-containing compounds in agrochemical materials and biomolecular drug molecules, research on methods for the construction of C–N bonds quickly and efficiently has become an important topic in synthetic chemistry. Carboxylic acids are inexpensive, stable, and non-toxic substances that are widely present in Nature, which makes them appealing as potential coupling partners for C(sp3)–N bond-forming reactions. Moreover, compared with the well-established transition-metal-catalyzed protocols, the rapid development of photoredox catalysis and electrochemical methods in recent years provides options for chemists to design new synthetic routes. In this short review, we concentrate on the decarboxylative C(sp3)–N coupling reactions mediated by visible light or electricity, with special attention on mechanistic insights.1 Introduction2 Photoredox-Mediated Decarboxylative C(sp3)–N Bond Formation2.1 Intramolecular Decarboxylation2.2 Intermolecular Decarboxylation3 Electrochemistry-Induced Decarboxylative C(sp3)–N Bond Formation3.1 Intramolecular Decarboxylation3.2 Intermolecular Decarboxylation4 Conclusions and Outlook

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Knipe, Peter C., and Jamie S. Sweet. "Catalytic Enantioselective Synthesis of C–N Atropisomeric Heterobiaryls." Synthesis 54, no. 09 (February 23, 2022): 2119–32. http://dx.doi.org/10.1055/s-0040-1719896.

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AbstractMolecules containing an atropisomeric C–N biaryl axis are gaining increasing attention in catalytic and medicinal chemistry. Despite this rising interest, relatively few approaches towards their catalytic enantioselective synthesis have been reported. Here we review these approaches, with a focus on the mechanism of asymmetric induction. Some common themes emerge: Brønsted acid catalysed cyclo-condensation and palladium-catalysed ring-closure are the most common and successful approaches. Meanwhile, the more direct but challenging axial C–N bond formation strategy remains in its infancy, with just two reports to-date. We hope this review will inform and inspire other researchers to develop new creative approaches to this important chemical motif.1 Introduction2 Cyclo-Condensation3 Proximal C–N Bond Formation4 Desymmetrisation of Intact Axes5 ortho-C–H Functionalisation6 Cycloaddition7 Axial C–N Bond Formation8 Atropisomeric N–N Axes: An Emerging Class of Heterobiaryls9 Conclusion and Outlook

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Surendra Reddy, G., A. Suresh Kumar, and Dhevalapally B. Ramachary. "Organocatalytic enone-azide [3 + 2]-cycloaddition: synthesis of functionally rich C/N-double vinyl 1,2,3-triazoles." Organic & Biomolecular Chemistry 18, no. 23 (2020): 4470–78. http://dx.doi.org/10.1039/d0ob00848f.

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C/N-Double vinyl-1,2,3-triazoles were furnished in very good yields with excellent selectivity by using an organocatalytic [3 + 2]-cycloaddition of enones with azides under ambient conditions. Many of the vinyl-1,2,3-triazoles have shown medicinal properties.

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Qiu, Mengyu, Xuegang Fu, Peng Fu, and Jianhui Huang. "Construction of aziridine, azetidine, indole and quinoline-like heterocycles via Pd-mediated C–H activation/annulation strategies." Organic & Biomolecular Chemistry 20, no. 7 (2022): 1339–59. http://dx.doi.org/10.1039/d1ob02146j.

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Gagné, Michel, and Brandon Moyer. "Taming Silylium Ions for Synthesis: N-Heterocycle Synthesis via Stereoselective C–C Bond Formation." Synlett 28, no. 18 (August 16, 2017): 2429–34. http://dx.doi.org/10.1055/s-0036-1590967.

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Silylium ions (formally [R3Si]+) have long been the subject of investigations and significant debate in both theoretical and experimental chemistry, but few catalytic, synthetic applications have been reported due to the exceptionally high reactivity and Lewis acidity of these elusive species. Results to be discussed include the application of easily accessible silylium ion catalysts to the stereoselective synthesis of various N-heterocyclic pyrrolidine and piperidine scaffolds. The tested substrates are derived from the chiral pool and can be obtained in three high-yielding steps from amino alcohols; subsequent stereoselective silylium ion catalyzed Prins cyclization and trapping with R3Si–Nu nucleophiles (e.g., Nu = H, allyl, azide, and enol ethers) results in novel nitrogen-containing polycyclic scaffolds with potential medicinal chemistry applications.

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Böser, Richard, Lars Denker, and René Frank. "N-Heterocyclic Carbene Adducts of Alkynyl Functionalized 1,3,2-Dithioborolanes." Molecules 24, no. 9 (April 30, 2019): 1690. http://dx.doi.org/10.3390/molecules24091690.

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Alkynyl functionalized boron compounds are versatile intermediates in the areas of medicinal chemistry, materials science, and optical materials. In particular, alkynyl boronate esters [R1−C≡C−B(OR2)2] are of interest since they provide reactivity at both the alkyne entity, with retention of the B−C bond or alkyne transfer to electrophilic substrates with scission of the latter. The boron atom is commonly well stabilized due to (i) the extraordinary strength of two B−O bonds, and (ii) the chelate effect exerted by a bifunctional alcohol. We reasoned that the replacement of a B−O for a B−S bond would lead to higher reactivity and post-functionalization in the resulting alkynyl boronate thioesters [R1−C≡C−B(S2X)]. Access to this poorly investigated class of compounds starts form chloro dithioborolane cyclo-Cl−B(S2C2H4) as a representative example. Whereas syntheses of three coordinate alkynyl boronate thioesters [R1−C≡C−B(S2X)] proved to be ineffective, the reactions of NHC-adducts (NHC = N-heterocyclic carbene) of cyclo-Cl-B(S2C2H4) afforded the alkyne substituted thioboronate esters in good yield. The products NHC−B(S2C2H4)(C≡C-R1) are remarkably stable towards water and air, which suggests their use as boron-based building blocks for applications akin to oxygen-based boronate esters.

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Zhang, Yitao, Balaram S. Takale, Fabrice Gallou, John Reilly, and Bruce H. Lipshutz. "Sustainable ppm level palladium-catalyzed aminations in nanoreactors under mild, aqueous conditions." Chemical Science 10, no. 45 (2019): 10556–61. http://dx.doi.org/10.1039/c9sc03710a.

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Greening-up aminations: a well-defined palladium pre-catalyst enables ppm-level Pd-catalyzed C–N cross couplings in water under very mild conditions. Comparisons using this protocol vs. traditional amination conditions for preparing key medicinal intermediates are demonstrated.

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Batalha, Pedro N., Luana da S. M. Forezi, Maria Clara R. Freitas, Nathalia M. de C. Tolentino, Ednilsom Orestes, José Walkimar de M. Carneiro, Fernanda da C. S. Boechat, and Maria Cecília B. V. de Souza. "Study on the regioselectivity of the N-ethylation reaction of N-benzyl-4-oxo-1,4-dihydroquinoline-3-carboxamide." Beilstein Journal of Organic Chemistry 15 (February 12, 2019): 388–400. http://dx.doi.org/10.3762/bjoc.15.35.

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4-Oxoquinolines are a class of organic substances of great importance in medicinal chemistry, due to their biological and synthetic versatility. N-1-Alkylated-4-oxoquinoline derivatives have been associated with different pharmacological activities such as antibacterial and antiviral. The presence of a carboxamide unit connected to carbon C-3 of the 4-oxoquinoline core has been associated with various biological activities. Experimentally, the N-ethylation reaction of N-benzyl-4-oxo-1,4-dihydroquinoline-3-carboxamide occurs at the nitrogen of the oxoquinoline group, in a regiosselective way. In this work, we employed DFT methods to investigate the regiosselective ethylation reaction of N-benzyl-4-oxo-1,4-dihydroquinoline-3-carboxamide, evaluating its acid/base behavior and possible reaction paths.

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Assefa Sisay, Melaku, Estifanos Ele Yaya, and Wendimagegn Mammo. "Essential oil and smoke components of Carissa spinarum." Bulletin of the Chemical Society of Ethiopia 36, no. 3 (July 15, 2022): 641–49. http://dx.doi.org/10.4314/bcse.v36i3.13.

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ABSTRACT. Carissa spinarum Linn. is an incense plant traditionally used in Ethiopia and other countries for the treatment of numerous diseases. It also exhibits different biological activities, and different classes of natural compounds were previously reported from the plant. In this study, the essential oil from the roots of C. spinarum together with medicinal smoke obtained from burnt roots of C. spinarum were analyzed by GC-MS. The essential oil of C. spinarum roots was predominantly composed of 2-hydroxyacetophenone (82.97%). The dominant components in the n-hexane soluble fraction of the smoke derived from the roots of C. spinarum were 2,6-dimethoxyphenol (14.16%), 2-methoxyphenol (10.34%) and 2-hydroxyacetophenone (9.51%). On the other hand, the major components in the MeOH-soluble fraction were 2,6-dimethoxyphenol (17.51%), 2-methoxyphenol (13.02%) and 2-hydroxyacetophenone (10.98%). The smoke derived from the roots of C. spinarum showed 92.60 ± 0.34% DPPH inhibition at concentration of 100 µg/mL. At the same concentration, standard ascorbic acid scavenged the DPPH radical by 96.09 ± 0.16%. This result supports the traditional medicinal use of the plant material as a skin-care and wound healing agent most likely due to the presence of simple phenols and other biologically active compounds. KEY WORDS: Carissa spinarum Linn., Medicinal smoke, Essential oil, Antioxidant activity, Phenolic compounds Bull. Chem. Soc. Ethiop. 2022, 36(3), 641-649. DOI: https://dx.doi.org/10.4314/bcse.v36i3.13

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Engeloch, Caroline, Ulrich Schopfer, Ingo Muckenschnabel, Francois Le Goff, Hervé Mees, Karoline Boesch, and Maxim Popov. "Stability of Screening Compounds in Wet DMSO." Journal of Biomolecular Screening 13, no. 10 (November 21, 2008): 999–1006. http://dx.doi.org/10.1177/1087057108326536.

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The impact of storage conditions on compound stability and compound solubility has been debated intensely over the past 5 years. At Novartis, the authors decided to opt for a storage concept that can be considered controversial because they are using a DMSO/water (90/10) mixture as standard solvent. To assess the effect of water in DMSO stocks on compound stability, the authors monitored the purity of a subset of 1404 compounds from ongoing medicinal chemistry projects over several months. The study demonstrated that 85% of the compounds were stable in wet DMSO over a 2-year period at 4 °C. This result validates the storage concept developed at Novartis as a pragmatic approach that takes advantage of the benefits of DMSO/water mixtures while mediating the disadvantages. In addition, the authors describe how purity data collected over the course of the chemical validation of high-throughput screening actives are used to improve the analytical quality of the Novartis screening deck. ( Journal of Biomolecular Screening 2008:999-1006)

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Nayak, Riddhi A., and Anvita D. Mangte. "Synthesis and Antimicrobial Studies of Novel N-Glycosyl Hydrazino Carbothioamide." Asian Journal of Chemistry 33, no. 1 (2020): 127–31. http://dx.doi.org/10.14233/ajchem.2021.22967.

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In view of applications of N-glycosylated compounds in medicinal chemistry and in many other ways, herein the synthesis of novel N-glycosyl hydrazino carbothioamides is reported. New N-glycosyl hydrazino carbothioamides were synthesized by the condensation of per-O-acetyl glycosyl isothiocyanate with different aromatic hydrazides. The newly synthesized compounds were characterized by using the IR, 1H NMR and mass spectral studies. Antimicrobial evaluation of the synthesized N-glycosyl hydrazino carbothioamide was also examined. Antimicrobial activities of the synthesized compound were evaluated against bacteria E. coli, P. aeruginosa, S. aureus, S. pyogenus and fungi C. albicans, A. niger and A. clavatus. All the N-glycosyl hydrazino carbothioamides exhibit promising antimicrobial activity.

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Kim, Dong, Yae Choi, Jaewon Shim, Yun-Sang Choi, Yun Kim, Mina Kim, and Min Kim. "Suppressive Effect of Arctium Lappa L. Leaves on Retinal Damage Against A2E-Induced ARPE-19 Cells and Mice." Molecules 25, no. 7 (April 9, 2020): 1737. http://dx.doi.org/10.3390/molecules25071737.

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Age-related macular degeneration (AMD) is a major cause of irreversible loss of vision with 80–90% of patients demonstrating dry type AMD. Dry AMD could possibly be prevented by polyphenol-rich medicinal foods by the inhibition of N-retinylidene-N-retinylethanolamine (A2E)-induced oxidative stress and cell damage. Arctium lappa L. (AL) leaves are medicinal and have antioxidant activity. The purpose of this study was to elucidate the protective effects of the extract of AL leaves (ALE) on dry AMD models, including in vitro A2E-induced damage in ARPE-19 cells, a human retinal pigment epithelial cell line, and in vivo light-induced retinal damage in BALB/c mice. According to the total phenolic contents (TPCs), total flavonoid contents (TFCs) and antioxidant activities, ALE was rich in polyphenols and had antioxidant efficacies on 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and 2′,7′-dichlorofluorescin diacetate (DCFDA) assays. The effects of ALE on A2E accumulation and A2E-induced cell death were also monitored. Despite continued exposure to A2E (10 μM), ALE attenuated A2E accumulation in APRE-19 cells with levels similar to lutein. A2E-induced cell death at high concentration (25 μM) was also suppressed by ALE by inhibiting the apoptotic signaling pathway. Furthermore, ALE could protect the outer nuclear layer (ONL) in the retina from light-induced AMD in BALB/c mice. In conclusion, ALE could be considered a potentially valuable medicinal food for dry AMD.

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Damdindorj, Mungunnaran, Gereltu Borjihan, Odontuya Gendaram, and Bayarmaa Bold. "Synthesis and antihyperlipidaemic activity of a new piperine derivative." Mongolian Journal of Chemistry 22, no. 48 (December 29, 2021): 13–18. http://dx.doi.org/10.5564/mjc.v22i48.1782.

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Long pepper (Piper longum Linn.) is widely used as a medicinal substance in traditional Ayurvedic medicine. Its major alkaloid piperine is the main active constituent with various therapeutic activities and has low solubility in water. In this study, a soluble new derivative of a piperine alkaloid, named N-leucinylpiperamide was synthesized. The animal experiment showed that N-leucinylpiperamide has more hypolipidemic effects than commercially available simvastatin and piperine in modulating serum lipids in Wistar male rats. At the amount of 10 mg/kg bw, it significantly reduced TC (-52.4%), TG (-61.7%), and LDL-C (-27.8%), respectively, and increased HDL-C (+147.4%) in the serum of the high-lipid model group. Furthermore, the synthesized N-leucinylpiperamide had no noticeable cytotoxicity against HepG2 cell line in vitro. Thus, our study shows that N-leucinylpiperamide has an ability to improve serum lipid profile in hyperlipidemic model rats and could be a valuable promising agent for the preventing hyperlipidemia.

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25

Amrati, Fatima Ez-Zahra, Mohammed Bourhia, Hamza Saghrouchni, Meryem Slighoua, Andriy Grafov, Riaz Ullah, Essam Ezzeldin, et al. "Caralluma europaea (Guss.) N.E.Br.: Anti-Inflammatory, Antifungal, and Antibacterial Activities against Nosocomial Antibiotic-Resistant Microbes of Chemically Characterized Fractions." Molecules 26, no. 3 (January 26, 2021): 636. http://dx.doi.org/10.3390/molecules26030636.

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Caralluma europaea (Guss.) N.E.Br.: (C. europaea) is a wild medicinal plant belonging to the family Apocynaceae. It is commonly used in traditional medicines for treating several diseases. The present work aims to evaluate the anti-inflammatory, antibacterial, and antifungal potentials of C. europaea fractions including hydro ethanol (ET CE), n-butanol (But CE), and polyphenol (Poly CE). The chemical composition of hydroethanol, n-butanol, and polyphenol-rich fractions from C. europaea were determined using GC-MS after silylation. The anti-inflammatory effect of hydroethanol, n-butanol, and polyphenol-rich fractions was studied by carrageenan-induced paw edema. Antibacterial and antifungal activities of hydroethanol, n-butanol, and polyphenol-rich fractions against Gram-positive bacteria, Gram-negative bacteria, and yeasts were assessed using the disc diffusion and micro-dilution assays. The findings of the chemical characterization affirmed the presence of interesting bioactive compounds in C. europaea fractions. The polyphenol-rich fraction was the best inhibitor of edema by75.68% after 6 h of treatment. The hydroethanol fraction was the most active against both bacteria and yeasts. This study contributes to society as it provides potential bioactive compounds in C. europaea extract, which may help in fighting nosocomial antibiotic-resistant microbes.

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26

Gülten, Şirin, Ufuk Gezer, and Elmas Aksanli Gündoğan. "Fast and Efficient One-Pot Three-Component Synthesis of Some 1,2,3,4- Tetrahydro-6-methyl-N-phenyl-5-pyrimidinecarboxamide Derivatives via Biginelli Condensation Reaction." Letters in Organic Chemistry 17, no. 5 (April 28, 2020): 366–71. http://dx.doi.org/10.2174/1570178616666190819142221.

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Tetrahydropyrimidine (THPM) synthesis has an enormous importance in organic chemistry and especially in pharmaceutical applications. Pyrimidines are the most active class of N-containing heterocyclic compounds and have different biological properties. The heterocyclic ring system with a thio group occupy a unique position in medicinal chemistry. This type of compounds play an important role in synthetic drugs and in biological processes. Dihydropyrimidinethione derivatives occur widely in nature. Several modifications of THPM-5-carboxamides have attracted considerable interest of medicinal chemists due to their pharmacological and therapeutic properties. A series of 1,2,3,4-tetrahydro- 2-pyrimidinone/thione derivatives bearing a phenylcarbamoyl group at C-5 position were synthesized by one-pot three-component Biginelli condensation reaction. The reaction of acetoacetanilide as the 1,3-dicarbonyl component with various aromatic aldehydes and urea/thiourea in the presence of a catalytic amount of p-toluenesulfonic acid monohydrate (PTSA·H2O) or concentrated HCl as an efficient catalyst leads to Biginelli compounds. We have prepared eight THPM 5-carboxamide derivatives, four of them are new compounds. Their structures were confirmed by spectroscopic techniques and elemental analysis. These compounds have potential applications in organic synthesis and medicinal chemistry. We have synthesized a series of THPM-5-carboxamides by simple and efficient threecomponent Biginelli condensation reaction. Significant benefits of the present procedure include: a) application of inexpensive, non-toxic, environmentally friendly and easily available catalysts, b) the reactions are easy to carry out without high temperature and the workup is very simple, c) the required reaction times are relatively short (30-80 min with HCl and 8-24 h with PTSA·H2O), d) compatibility with various functional groups, e) the products are isolated in good to excellent yields (50-95%).

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Yu, Da Qing, Xiao Jing Han, Ting Yu Shan, Rui Xu, Jin Hu, Wang Xing Cheng, Liang Ping Zha, and Hua Sheng Peng. "Microscopic Characteristic and Chemical Composition Analysis of Three Medicinal Plants and Surface Frosts." Molecules 24, no. 24 (December 12, 2019): 4548. http://dx.doi.org/10.3390/molecules24244548.

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The accumulation of chemical constituents of some medicinal plants, such as Paeonia ostii T. Hong et J. X. Zhang, Houpoëa officinalis (Rehder and E. H. Wilson) N. H. Xia and C. Y. Wu. and Atractylodes lancea (Thunb.) DC, can precipitate on the surface and form frosts after natural or artificial intervention. The characteristics of these three medicinal plants and their frosts were analyzed by light microscope, polarizing microscope, stereomicroscope, and metalloscope. The results of ordinary Raman of P. ostii and H. officinalis showed that the frosts of P. ostii matched paeonol, while that of H. officinalis matched magnolol and honokiol. In P. ostii and its frost, 19 peaks were identified by UPLC-Q/TOF-MS, and the main component was paeonol. Eleven components were identified in H. officinalis and its frosts, and the main components were magnolol and honokiol. A. lancea and its frosts were analyzed by gas chromatography-mass spectrometry (GC-MS), 21 were identified, and its main components were hinesol and β-eudesmol. These three medicinal plants accumulate compounds and precipitate frosts on the surface. The results show that the components of the frosts provide a basis for quality evaluation and research on similar medicinal plants, and reveals the scientific connotation of “taking the medicinal materials’ precipitated frosts as the best” of P. ostii, H. officinalis, and A. lancea, to some extent.

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28

Bai, Xiuyun, Hengye Chen, Wanjun Long, Wei Lan, Siyu Wang, Guanghua Lei, Yuting Guan, Jian Yang, and Haiyan Fu. "Accurate Traceability of Stable C, H, O, N Isotope Ratios and Multi-Element Analysis Combined with Chemometrics for Chrysanthemi Flos ‘Hangbaiju’ from Different Origins." Chemosensors 10, no. 12 (December 12, 2022): 529. http://dx.doi.org/10.3390/chemosensors10120529.

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Chrysanthemi Flos ‘Hangbaiju’ (HBJ) is a common Chinese medicinal material with the same origin as the medicinal and edible cognate plant in China, whose quality is seriously affected by the place of origin. In this study, four stable isotope ratios (δ15N, δ2H, δ13C, and δ18O) and 44 elements were detected and analyzed in 191 HBJ flower samples from six locations in China to trace the origin of HBJ. An ANOVA analysis of δ15N, δ2H, δ13C, and δ18O values, as well as milti-elements, showed that there were significant differences among the six places of origin. Partial least squares discriminant analysis (PLSDA) and one-class partial least squares discriminant analysis (OPLS-DA) models were established to trace the origin of HBJ from these six locations. The results showed that the classification effect of the PLSDA model is poor; however, the established OPLS-DA model can distinguish between products of national geographic origin (Tongxiang City, Zhejiang Province, China) and samples from other origins, among which Ni, Mo, δ13C, Cu, and Ce elements (VIP > 1) contribute the most to this classification. Therefore, this study provides a new method for tracing the origins of HBJ, which is of great significance for the protection of origin labeling of products.

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Jung, In-Geun, Jae-Young Jeong, Seung-Hoon Yum, and You-Jin Hwang. "Inhibitory Effects of Selected Medicinal Plants on Bacterial Growth of Methicillin-Resistant Staphylococcus aureus." Molecules 27, no. 22 (November 11, 2022): 7780. http://dx.doi.org/10.3390/molecules27227780.

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Methicillin-resistant Staphylococcus aureus (MRSA) is a serious threat to global public health due to its capacity of tolerate conventional antibiotics. Medicinal plants are traditionally used to treat infectious diseases caused by bacterial pathogens. In the present study, 16 medicinal plants were screened for antibacterial activities to preselect more effective species. Ethanol extracts of selected medicinal plants (Caesalpinia sappan L., Glycyrrhiza uralensis Fisch., Sanguisorba officinalis L., and Uncaria gambir Roxb) were partitioned successively with different solvents (n-hexane, chloroform, ethyl acetate, 1-butanol, and water). Disc diffusion assay and broth microdilution were performed to evaluate the antibacterial activities of plant extracts and fractions against Staphylococcus aureus strains. Furthermore, the cytotoxicity of the extracts and fractions was determined against the human hepatoma (HepG2) and human lung carcinoma (A549) cell lines using a trypan blue exclusion method. A few extracts and fractions showed significant inhibitory effects on the bacterial growth of all tested strains, including multidrug-resistance (MDR) clinical isolates. The ethyl acetate fraction of C. sappan had the most potent effects with minimum inhibitory/bactericidal concentrations (MIC/MBC) of 31.2/62.5 μg/mL and showed low cytotoxicity with over 90% cell viability in both cells. Our results suggest that medicinal plants have considerable potential as alternatives to conventional antibiotics.

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Innes, Dylan, Michael V. Perkins, Andris J. Liepa, and Craig L. Francis. "N,N-Dialkyl-N′-Chlorosulfonyl Chloroformamidines in Heterocyclic Synthesis. Part XIV. Synthesis and Reactivity of the New Benzo[4,5]imidazo[1,2-b][1,2,6]thiadiazine Ring System." Australian Journal of Chemistry 71, no. 1 (2018): 58. http://dx.doi.org/10.1071/ch17255.

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N,N-Dialkyl-N′-chlorosulfonyl chloroformamidines 1 underwent regioselective reactions with the 1,3-NCC bis-nucleophilic 1H-benzimidazole-2-acetonitriles 4 and related compounds to produce benzo[4,5]imidazo[1,2-b][1,2,6]thiadiazine dioxides 6, 9, 12, and 14, representatives of a new ring system. Reaction of dichlorides 1 with trifluoroacetyl derivative 16 afforded benzo[4,5]imidazo[1,2-c]pyrimidines 19 and 20. An N-acyl and some N-alkyl derivatives of benzimidazo-thiadiazines 6 were prepared to demonstrate the potential of this new ring system as a novel scaffold for synthetic and medicinal chemistry applications. Treatment of the 4-cyano-5-methyl-benzimidazo-thiadiazine 26c with LiAlH4 resulted in an unexpected and remarkable conversion of the nitrile to give the 4,5-dimethyl-benzimidazo-thiadiazine 29.

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31

Semenyuk, Pavel I., Lidia P. Kurochkina, Lauri Mäkinen, Vladimir I. Muronetz, and Sami Hietala. "Thermocontrolled Reversible Enzyme Complexation-Inactivation-Protection by Poly(N-acryloyl glycinamide)." Polymers 13, no. 20 (October 19, 2021): 3601. http://dx.doi.org/10.3390/polym13203601.

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A prospective technology for reversible enzyme complexation accompanied with its inactivation and protection followed by reactivation after a fast thermocontrolled release has been demonstrated. A thermoresponsive polymer with upper critical solution temperature, poly(N-acryloyl glycinamide) (PNAGA), which is soluble in water at elevated temperatures but phase separates at low temperatures, has been shown to bind lysozyme, chosen as a model enzyme, at a low temperature (10 °C and lower) but not at room temperature (around 25 °C). The cooling of the mixture of PNAGA and lysozyme solutions from room temperature resulted in the capturing of the protein and the formation of stable complexes; heating it back up was accompanied by dissolving the complexes and the release of the bound lysozyme. Captured by the polymer, lysozyme was inactive, but a temperature-mediated release from the complexes was accompanied by its reactivation. Complexation also partially protected lysozyme from proteolytic degradation by proteinase K, which is useful for biotechnological applications. The obtained results are relevant for important medicinal tasks associated with drug delivery such as the delivery and controlled release of enzyme-based drugs.

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32

Bisz, Elwira, Pamela Podchorodecka, Hengzhao Li, Wioletta Ochędzan-Siodłak, Jie An, and Michal Szostak. "Sequential Iron-Catalyzed C(sp2)–C(sp3) Cross-Coupling of Chlorobenzamides/Chemoselective Amide Reduction and Reductive Deuteration to Benzylic Alcohols." Molecules 28, no. 1 (December 27, 2022): 223. http://dx.doi.org/10.3390/molecules28010223.

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Benzylic alcohols are among the most important intermediates in organic synthesis. Recently, the use of abundant metals has attracted significant attention due to the issues with the scarcity of platinum group metals. Herein, we report a sequential method for the synthesis of benzylic alcohols by a merger of iron catalyzed cross-coupling and highly chemoselective reduction of benzamides promoted by sodium dispersion in the presence of alcoholic donors. The method has been further extended to the synthesis of deuterated benzylic alcohols. The iron-catalyzed Kumada cross-coupling exploits the high stability of benzamide bonds, enabling challenging C(sp2)–C(sp3) cross-coupling with alkyl Grignard reagents that are prone to dimerization and β-hydride elimination. The subsequent sodium dispersion promoted reduction of carboxamides proceeds with full chemoselectivity for the C–N bond cleavage of the carbinolamine intermediate. The method provides access to valuable benzylic alcohols, including deuterium-labelled benzylic alcohols, which are widely used as synthetic intermediates and pharmacokinetic probes in organic synthesis and medicinal chemistry. The combination of two benign metals by complementary reaction mechanisms enables to exploit underexplored avenues for organic synthesis.

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Gao, Meng, Wenting Zhao, Hongyi Zhao, Ziyun Lin, Dongfeng Zhang, and Haihong Huang. "An efficient and facile access to highly functionalized pyrrole derivatives." Beilstein Journal of Organic Chemistry 14 (April 20, 2018): 884–90. http://dx.doi.org/10.3762/bjoc.14.75.

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A straightforward and one-pot synthesis of pyrrolo[3,4-c]pyrrole-1,3-diones via Ag(I)-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with N-alkyl maleimide, followed by readily complete oxidation with DDQ, has been successfully developed. Further transformation with alkylamine/sodium alkoxide alcohol solution conveniently afforded novel polysubstituted pyrroles in good to excellent yields. This methodology for highly functionalized pyrroles performed well over a broad scope of substrates. It is conceivable that this efficient construction method for privileged pyrrole scaffolds could deliver more active compounds for medicinal chemistry research.

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34

Shafiq, Nusrat, Farah Yasmin, Sadia Noreen, Alina Shahzad, Zill-I.-huma Nazli, Shagufta Parveen, Basharat Ali, Zaheer Ahmad, Maryam Rashid, and Muhammad Bilal. "Phytochemical Profiling of Medicinal Plants Extracts and Their Antioxidant and Anticancer Potentialities Against Human Liver Cancer (Hep G2) Cell Lines." Revista de Chimie 72, no. 1 (February 3, 2021): 100–110. http://dx.doi.org/10.37358/rc.21.1.8407.

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Although Pakistan is stacked with enormous varieties of medicinal plants, only a little proportion of these plants has been evaluated for their medicinal and therapeutic properties. Herein, four indigenous medicinal plants Citrus sinenesis, Citrus paradiasii, Moringa olifera, and Hibiscus rosa-sinenesis were collected and subjected to phytochemical analyses to scrutinize the presence of secondary metabolites. Qualitative analy�sis showed the presence of an array of secondary metabolites in the selected plants, which were further corroborated by high-performance liquid chromatography. Results revealed the presence of 33.24, 21.04, 15.2 ppm gallic acid in methanol, ethyl acetate and n-hexane fraction of C. sinensis peels extract, respectively. C. paradaissi peels consist of 24.06, and 18.24 ppm of gallic acid and caffeic acid, respectively, in methanol and chloroform fractions, whereas its methanolic seeds extract contain caffeic acid as a major component (10.63 ppm). H. rosa-sinenesis has shown p-coumaric acid, caffeic acid, and gallic acid at 35.26, 15.04, and 11.4 ppm, respectively. M. olifera contained 3.24 ppm gallic acid in pods extract while stems and leaves extract contain a very low amount. Anticancer profile evinced that Citrus sinensis extract showed the highest percent inhibition (142.746%) of human liver cancer (Hep G2) cell lines followed by H. rosa-sinensis (132.49%), C. paradaisii (82.39%) and M. olifera (68.0%). The determined IC50 values for antioxidant activity were C. sinenesis (IC50=0.49 mM), C. paradaisii (IC50=0.43 mM), M. olifera (IC50=0.42 mM) and H. rosa-sinensis (IC50=0.41 mM). Conclusively, the selected plants could be an effective alternative and deliverable chemical therapeutic to the pharmaceutical industry due to their excellent biological effects.

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Zhang, Lin, Wei Xie, Xiaojun Teng, Kui Wang, Wei Xie, and Caiyan Wang. "Improving the Extraction of Active Ingredients from Medicinal Plants by XynA Modification." Journal of Chemistry 2022 (February 3, 2022): 1–8. http://dx.doi.org/10.1155/2022/2483797.

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Active ingredients of medicinal plants have unique pharmacological and clinical effects. However, conventional extraction technology has many disadvantages, such as long-time and low-efficiency. XynA-assisted extraction may overcome such problems, since the plant cell wall is mainly composed of cellulose. Based on the three-dimensional protein structure, we found the C-terminal domain and N-terminal domain twisted together and resulted in more flexibility. We carried out a series of truncations, with XynA_ΔN36 getting more yields of active ingredients. As shown by HPLC analysis, the efficiencies for extraction of salvianic acid A and berberine from Salvia miltiorrhiza and Phellodendron chinense were increased by approximately 38.14% and 35.20%, respectively, compared with the conventional extraction protocol. The yields of the two compounds reached 2.84 ± 0.05 mg g−1 and 3.52 ± 0.14 mg g−1, respectively. Above all, XynA_ΔN36 can be applied to the extraction of salvianic acid A and berberine, and this study provides a novel enzyme for the extraction technology, which aids rational utilization and quality control of medicinal plants.

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Asilbekova, Daniya Tolimbekovna, and Khairulla Mamadievich Bobakulov. "STUDY OF LIPIDS, FATTY ACIDS AND LIPOPHILIC SUBSTANCES OF СONSOLIDA AMBIGUA (L.) P.W. BALL & HEYWOOD AND NIGELLA SATIVA L. SEEDS." chemistry of plant raw material, no. 1 (March 16, 2021): 105–12. http://dx.doi.org/10.14258/jcprm.2021018384.

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The seeds of two medicinal plants from Ranunculaceae family – Consolida ambigua (L.) P.W. Ball & Heywood (Syn. Сonsolida ajacis Schur, ajacsova consolida, larkspur) and Nigella sativa L. (black cumin) cultivated in Uzbekistan was analyzed. Free and bound lipids were isolated from the seeds, the fatty acid composition of their neutral, glyco- and phospholipids was established. It was revealed that unsaturated components dominate among the ordinary fatty acids of seed lipids – oleic (C. ambigua) and linoleic (N. sativa). Their rare homologues – 11(Z)-eicosaenoic (C. ambigua) and 11,14(Z,Z)-eicosadienoic (Nigella sativa) acids were esterified mainly in the triacylglycerol molecules, and were found as free fatty acids of the studied oils. The major compounds among the 26 constituents of the essential oil of N. sativa seeds were p-cymene, terpinolene, β-pinene, limonene and sabinene.

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Cilia, Giovanni, Giacomo Luchetti, and Antonio Nanetti. "Polymorphism of 16s rRNA Gene: Any Effect on the Biomolecular Quantitation of the Honey Bee (Apis mellifera L., 1758) Pathogen Nosema ceranae?" Applied Sciences 12, no. 1 (January 2, 2022): 422. http://dx.doi.org/10.3390/app12010422.

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The microsporidian Nosema ceranae is a severe threat to the western honey bee Apis mellifera, as it is responsible for nosemosis type C, which leads the colonies to dwindle and collapse. Infection quantification is essential to clinical and research aims. Assessment is made often with molecular assays based on rRNA genes, which are present in the N. ceranae genome as multiple and polymorphic copies. This study aims to compare two different methods of Real-Time PCR (qPCR), respectively relying on the 16S rRNA and Hsp70 genes, the first of which is described as a multiple and polymorphic gene. Young worker bees, hatched in the laboratory and artificially inoculated with N. ceranae spores, were incubated at 33 °C and subject to different treatment regimens. Samples were taken post-infection and analyzed with both qPCR methods. Compared to Hsp70, the 16S rRNA method systematically detected higher abundance. Straightforward conversion between the two methods is made impossible by erratic 16s rRNA/Hsp70 ratios. The 16s rRNA polymorphism showed an increase around the inoculated dose, where a higher prevalence of ungerminated spores was expected due to the treatment effects. The possible genetic background of that irregular distribution is discussed in detail. The polymorphic nature of 16S rRNA showed to be a limit in the infection quantification. More reliably, the N. ceranae abundance can be assessed in honey bee samples with methods based on the single-copy gene Hsp70.

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Rasool, Rabia, Inam Ullah, Samiah Shahid, Bismillah Mubeen, Syed Sarim Imam, Sultan Alshehri, Mohammed M. Ghoneim, et al. "In Vivo Assessment of the Ameliorative Impact of Some Medicinal Plant Extracts on Lipopolysaccharide-Induced Multiple Sclerosis in Wistar Rats." Molecules 27, no. 5 (February 28, 2022): 1608. http://dx.doi.org/10.3390/molecules27051608.

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Multiple sclerosis is a chronic autoimmune disorder that leads to the demyelination of nerve fibers, which is the major cause of non-traumatic disability all around the world. Herbal plants Nepeta hindustana L., Vitex negundo L., and Argemone albiflora L., in addition to anti-inflammatory and anti-oxidative effects, have shown great potential as neuroprotective agents. The study was aimed to develop a neuroprotective model to study the effectiveness of herbal plants (N. hindustana, V. negundo, and A. albiflora) against multiple sclerosis. The in vivo neuroprotective effects of ethanolic extracts isolated from N. hindustana, V. negundo, and A. albiflora were evaluated in lipopolysaccharides (LPS) induced multiple sclerosis Wistar rat model. The rat models were categorized into seven groups including group A as normal, B as LPS induced diseased group, while C, D, E, F, and G were designed as treatment groups. Histopathological evaluation and biochemical markers including stress and inflammatory (MMP-6, MDA, TNF-α, AOPPs, AGEs, NO, IL-17 and IL-2), antioxidant (SOD, GSH, CAT, GPx), DNA damage (Isop-2α, 8OHdG) as well as molecular biomarkers (RAGE, Caspase-8, p38) along with glutamate, homocysteine, acetylcholinesterase, and myelin binding protein (MBP) were investigated. The obtained data were analyzed using SPSS version 21 and GraphPad Prism 8.0. The different extract treated groups (C, D, E, F, G) displayed a substantial neuroprotective effect regarding remyelination of axonal terminals and oligodendrocytes migration, reduced lymphocytic infiltrations, and reduced necrosis of Purkinje cells. The levels of stress, inflammatory, and DNA damage markers were observed high in the diseased group B, which were reduced after treatments with plant extracts. The antioxidant activity was significantly reduced in diseased induced group B, however, their levels were raised after treatment with plant extract. Group F (a mélange of all the extracts) showed the most significant change among all other treatment groups (C, D, E, G). The communal dose of selected plant extracts regulates neurodegeneration at the cellular level resulting in restoration and remyelination of axonal neurons. Moreover, 400 mg/kg dose of three plants in conjugation (Group F) were found to be more effective in restoring the normal activities of all measured parameters than independent doses (Group C, D, E) and is comparable with standard drug nimodipine (Group G) clinically used for the treatment of multiple sclerosis. The present study, for the first time, reported the clinical evidence of N. hindustana, V. negundo, and A. albiflora against multiple sclerosis and concludes that all three plants showed remyelination as well neuroprotective effects which may be used as a potential natural neurotherapeutic agent against multiple sclerosis.

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39

Katugampala, Supun, Inoka C. Perera, Chandrika Nanayakkara, and Theshini Perera. "Synthesis, Characterization, and Antimicrobial Activity of Novel Sulfonated Copper-Triazine Complexes." Bioinorganic Chemistry and Applications 2018 (August 29, 2018): 1–7. http://dx.doi.org/10.1155/2018/2530851.

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Metallotriazine complexes possess interesting biological and medicinal properties, and the present study focuses on the synthesis, characterization, and antimicrobial activity of four novel copper-triazine derivatives in search of potent antibacterial and antifungal drug leads. In this study, 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine-4,4′-disulfonic acid monosodium salt (L1, ferrozine) and 3-(2-pyridyl)-5,6-di(2-furyl)-1,2,4-triazine-5,5′-disulfonic acid disodium salt (L2, ferene) have been used as ligands to study the complexation towards copper(II). The synthesized complexes, [CuCl2(ferrozine)]·7H2O·MeOH (1), [CuCl2(ferrozine)2]·5H2O·MeOH (2), [CuCl2(ferene)]·H2O·MeOH (3), and [CuCl2(ferene)2]·H2O·MeOH (4), have been characterized spectroscopically, and preliminary bioassays have been carried out. FTIR spectroscopic data have shown that N=N and C=N stretching frequencies of complexes have been shifted towards lower frequencies in comparison with that of the ligands, confirming new bond formation between Cu and N, which in turn lowers the strength of N=N and C=N bonds. In addition, a bathochromic shift has been observed for UV-visible spectra of complexes (1), (2), (3), and (4). Furthermore, elemental analysis data have been useful to obtain empirical formulas of these complexes and to establish the purity of each complex. Complexes (1) and (2) have shown antibacterial activity for bothS. aureus(ATCC® 25923) andE. coli(ATCC® 25922) at 1 mg/disc concentration, and ferrozine has shown a larger inhibition zone against the clinical sample ofC. albicansat 1 mg/disc concentration in comparison with the positive control, fluconazole.

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Chuang, Lu-Te, Ya-Hsin Shih, Wen-Cheng Huang, Lie-Chwen Lin, Chin Hsu, Jong-Ho Chyuan, Tsung-Hsien Tsai, and Po-Jung Tsai. "In Vitro and In Vivo Screening of Wild Bitter Melon Leaf for Anti-Inflammatory Activity against Cutibacterium acnes." Molecules 25, no. 18 (September 18, 2020): 4277. http://dx.doi.org/10.3390/molecules25184277.

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Cutibacterium acnes (formerly Propionibacterium acnes) is a key pathogen involved in the development and progression of acne inflammation. The numerous bioactive properties of wild bitter melon (WBM) leaf extract and their medicinal applications have been recognized for many years. In this study, we examined the suppressive effect of a methanolic extract (ME) of WBM leaf and fractionated components thereof on live C. acnes-induced in vitro and in vivo inflammation. Following methanol extraction of WBM leaves, we confirmed anti-inflammatory properties of ME in C. acnes-treated human THP-1 monocyte and mouse ear edema models. Using a bioassay-monitored isolation approach and a combination of liquid–liquid extraction and column chromatography, the ME was then separated into n-hexane, ethyl acetate, n-butanol and water-soluble fractions. The hexane fraction exerted the most potent anti-inflammatory effect, suppressing C. acnes-induced interleukin-8 (IL-8) production by 36%. The ethanol-soluble fraction (ESF), which was separated from the n-hexane fraction, significantly inhibited C. acnes-induced activation of mitogen-activated protein kinase (MAPK)-mediated cellular IL-8 production. Similarly, the ESF protected against C. acnes-stimulated mouse ear swelling, as measured by ear thickness (20%) and biopsy weight (23%). Twenty-four compounds in the ESF were identified using gas chromatograph–mass spectrum (GC/MS) analysis. Using co-cultures of C. acnes and THP-1 cells, β-ionone, a compound of the ESF, reduced the production of IL-1β and IL-8 up to 40% and 18%, respectively. β-ionone also reduced epidermal microabscess, neutrophilic infiltration and IL-1β expression in mouse ear. We also found evidence of the presence of anti-inflammatory substances in an unfractionated phenolic extract of WBM leaf, and demonstrated that the ESF is a potential anti-inflammatory agent for modulating in vitro and in vivo C. acnes-induced inflammatory responses.

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Hasserodt, Jens, Arnaud Gautier, Romain Barbe, and Michael Waibel. "ChemInform Abstract: The N→C=O Interaction: A Weak Bond with Attractive Properties for the Deliberate Exploitation in Medicinal and Supramolecular Chemistry." ChemInform 42, no. 24 (May 19, 2011): no. http://dx.doi.org/10.1002/chin.201124215.

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Tang, Xue Song, and Ming Li. "Synthesis of n-Hexadecylphosphonic Acid-Coated Monodisperse Fe₃O₄ Superparamagnetic Nanoparticles." Key Engineering Materials 512-515 (June 2012): 170–73. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.170.

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Monodisperse Fe3O4 Superparamagnetic Nanoparticles Were Synthesized in N-Hexadecylphosphonic Acid/ Cyclohexane/ Water/ Ethanol Microemulsion under Solvothermal Conditions at 100°C. the Crystal Structure and Particle Size of Synthesized Fe3O4 Were Observed by X-Ray Diffraction (XRD) as Well as Transmission Electron Microscopy (TEM). the Results Show that the Nanoparticles Have a Cubic Crystal System and a Average Particle Size of about 10nm. each Nanoparticle Has a Single Crystal Structure. the Surface Chemistry of Synthesized Fe3O4 Nanoparticles Was Characterized by Fourier Transform Infrared Spectroscopy (FTIR), Indicating that the Nanoparticles Were Covered by a Layer of N-Hexadecylphosphonic Acid, which Made the Nanoparticles Totally Lipophilic. Magnetic Properties of the Nanoparticles Were Investigated by Using Vibrating Sample Magnetometer (VSM). the Result Reveals that the Saturation Magnetization (Ms) of the Nanoparticles Is Higher than 40 Emu/G and the Coercive Force Is near to 0. the Monodisperse Fe3O4 Nanoparticles Have Superparamagnetic Property and May Find Potential Applications in many Fields, such as Ferrofluids, Drug Loading and Release, Selective Biomolecular Separation and MRI.

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Doan, Chien, Thi Tran, Minh Nguyen, Van Nguyen, Anh Nguyen, and San-Lang Wang. "Anti-α-Glucosidase Activity by a Protease from Bacillus licheniformis." Molecules 24, no. 4 (February 15, 2019): 691. http://dx.doi.org/10.3390/molecules24040691.

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Anti-α-glucosidase (AAG) compounds have received great attention due to their potential use in treating diabetes. In this study, Bacillus licheniformis TKU004, an isolated bacterial strain from Taiwanese soil, produced AAG activity in the culture supernatant when squid pens were used as the sole carbon/nitrogen (C/N) source. The protein TKU004P, which was isolated from B. licheniformis TKU004, showed stronger AAG activity than acarbose, a commercial anti-diabetic drug (IC50 = 0.1 mg/mL and 2.02 mg/mL, respectively). The molecular weight of TKU004P, determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), was 29 kDa. High-performance liquid chromatography (HPLC) analysis showed that TKU004P may be a protease that demonstrates AAG activity by degrading yeast α-glucosidase. Among the four chitinous sources of C/N, TKU004P produced the highest AAG activity in the culture supernatant when shrimp head powder was used as the sole source (470.66 U/mL). For comparison, 16 proteases, were investigated for AAG activity but TKU004P produced the highest levels. Overall, the findings suggest that TKU004P could have applications in the biochemical and medicinal fields thanks to its ability to control the activity of α-glucosidase.

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Lu, Cheng Wei, Tzu Yu Lin, and Su Jane Wang. "11-Keto-β-Boswellic Acid Attenuates Glutamate Release and Kainic Acid-Induced Excitotoxicity in the Rat Hippocampus." Planta Medica 86, no. 06 (February 25, 2020): 434–41. http://dx.doi.org/10.1055/a-1107-9337.

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AbstractExcessive glutamate concentration induces neuronal death in acute brain injuries and chronic neurodegenerative diseases. Natural compounds from medicinal plants have attracted considerable attention for their use in the prevention and treatment of neurological disorders. 11-Keto-β-boswellic acid, a triterpenoid found in the medicinal plant Boswellia serrata, has neuroprotective potential. The present study investigated the effect of 11-keto-β-boswellic acid on glutamate release in vitro and kainic acid-induced glutamate excitotoxicity in vivo in the rat hippocampus. In rat hippocampal nerve terminals (synaptosomes), 11-keto-β-boswellic acid dose-dependently inhibited 4-aminopyridine-stimulated glutamate release. This effect was dependent on extracellular calcium, persisted in the presence of the glutamate transporter inhibitor DL-threo-β-benzyloxyaspartate, and was blocked by the vesicular transporter inhibitor bafilomycin A1. In addition, 11-keto-β-boswellic acid reduced the 4-aminopyridine-induced increase in intrasynaptosomal Ca2+ levels. The N- and P/Q-type channel blocker ω-conotoxin MVIIC and the protein kinase A inhibitor H89 significantly suppressed the 11-keto-β-boswellic acid-mediated inhibition of glutamate release, whereas the intracellular Ca2+-releasing inhibitors dantrolene, CGP37157, and xestospongin C, mitogen-activated protein kinase inhibitor PD98059, as well as protein kinase C inhibitor calphostin C had no effect. In a rat model of excitotoxicity induced by intraperitoneal kainic acid injection (15 mg/kg), intraperitoneal 11-keto-β-boswellic acid administration (10 or 50 mg/kg) 30 min before kainic acid injection considerably ameliorated kainic acid-induced glutamate concentration elevation and CA3 neuronal death. These data suggested that 11-keto-β-boswellic acid inhibits glutamate release from the rat hippocampal synaptosomes by suppressing N- and P/Q-type Ca2+ channels and protein kinase A activity, as well as exerts protective effects against kainic acid-induced excitotoxicity in vivo.

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Al-Ostoot, Fares Hezam, Jigmat Stondus, Sumati Anthal, Geetha Doddenahally Venkatesh, Yasser Hussein Eissa Mohammed, Mandayam Anandalwar Sridhar, Shaukath Ara Khanum, and Rajni Kant. "Synthesis, spectroscopic and X-ray crystallographic analysis of N-(2-(2-(4-chlorophenoxy)acetamido)phenyl)-1H-indole-2-carboxamide." European Journal of Chemistry 10, no. 3 (September 30, 2019): 234–38. http://dx.doi.org/10.5155/eurjchem.10.3.234-238.1874.

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Medicinal chemistry of indole analogs constitutes important therapeutic agents with anti-oxidant, anti-HIV and anti-cancer activities. Indole nucleus is frequently found in synthetic and natural products, pharmaceuticals, functional materials, agrochemicals, etc. The title compound, N-(2-(2-(4-chlorophenoxy)acetamido)phenyl)-1H-indole-2-carboxamide (5), has been synthesized in good yield by stirring the compound N-(2-aminophenyl)-2-(4-chlorophenoxy)acetamide (3) with 1H-indole-2-carboxylic acid (4), in dry dichloromethane followed by the addition of 2,6-lutidine, and o-(benzotriazol-1-yl)-N,N,N',N'-tetramethyl uraniumtetrafluoroborate in cooled condition. Compound 5 was synthesized and characterized by the conventional spectroscopic techniques (1H NMR, 13C NMR and LC-MS) and the three-dimensional structure was elucidated by using single crystal X-ray diffraction methods. It crystallizes in the monoclinic crystal system with space group P21/c. The structure was solved by direct methods and refined by full matrix least square procedure to a final R value of 0.043 for 2490 observed reflections. Three intra-molecular interactions of the type N-H···N and C-H···N were observed. The packing of molecules in the unit cell is governed by N-H···O and C-H···O intermolecular H-boned interactions which leads to the formation of infinite staking chain along [001] direction. In addition, two weak C-H···π interactions also contribute to molecular packing.

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Dhanalakshmi, G., Velu Saravanan, Arasambattu K. Mohanakrishnan, and S. Aravindhan. "Synthesis, Crystal Structure, Hirshfeld Surface, Energy Framework and Molecular Docking Analysis of Two Novel Carbazole Derivatives." Asian Journal of Chemistry 31, no. 12 (November 16, 2019): 3017–28. http://dx.doi.org/10.14233/ajchem.2019.22430.

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Carbazole derivatives are important compounds from medicinal point of view because of their widespread biological significance. In the present work two compounds 7-(4-chlorophenyl)-5-methyl- 12-(phenylsulfonyl)-12H-naphtho[1,2-b]carbazole (I) and 7-ethyl-5-methyl-12-(phenylsulfonyl)-12Hnaphtho[ 1,2-b]carbazole (II) have been synthesized and characterized by XRD, Hirshfeld surface, energy framework and docking analysis. Single crystal X-ray diffraction analysis shows that the compound I crystallizes in monoclinic system with space group P21/n whereas compound II crystallizes in triclinic with space group P-1. In both compounds there are two intramolecular C-H···O hydrogen bonds, which generates two S (6) ring motifs. The crystal packing is stabilized through weak C-H···O and C-H···Cl interactions. The molecules also features C-H···π interactions. The intermolecular interactions of both compounds were analyzed using Hirshfeld surface analysis and two dimensional fingerprint plots, which was confirmed by the XRD data. Energy frameworks were used to calculate the intermolecular interaction energies and their distribution over the crystal structure. Molecular docking studies show that the compounds exhibits antitumor activity.

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BACKES, Luana Taís Hartmann, Telma Elita BERTOLIN, Silvana Souza ROMAN, Janaine de Oliveira PAIVA, Vanusa MANFREDINI, Luciane Noal CALIL, Daliane Paula FATURI, and Adelina MEZZARI. "ASCORBIC ACID AND THE PROTECTIVE EFFECT IN SWISS MICE TREATED WITH GREEN TEA INFUSIONS." Periódico Tchê Química 12, no. 24 (August 20, 2015): 17–27. http://dx.doi.org/10.52571/ptq.v12.n24.2015.17_p_24_pgs_17_27.pdf.

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The use of medicinal plants is expressive because it’s beneficial effects, however the dosages some times are not adjusted. The study had for objective to investigate the toxicity of the green tea and the protective effect of vitamin C. Had been used 36 mice swiss, distributed in 6 groups (n=6): Control group with 1 ml/kg of saline solution 0.9%; Experimental group 1 with extract of Camellia sinensis in 0,5% concentration; Experimental group 2 with extract of Camellia sinensis in 10% concentration; Experimental group 3 with extract of Camellia sinensis in 0,5% concentration associate with vitamin C in 40mg/mL concentration; Experimental group 4 with extract of Camellia sinensis in 10% concentration associate with vitamin C in 40mg/mL concentration and Experimental group 5 with vitamin C solution in 40mg/mL concentration. The results had been significant for corporal weight and agencies (liver, kidneys, dull and brain) in the group of bigger concentration of green tea and in the groups where vitamin C was associated, allowing itself to suggest a light toxicity in the groups that had received these treatments.

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Jeffs, Joshua W., Nilojan Jehanathan, Stephanie M. F. Thibert, Shadi Ferdosi, Linda Pham, Zachary T. Wilson, Christian Breburda, and Chad R. Borges. "Delta-S-Cys-Albumin: A Lab Test that Quantifies Cumulative Exposure of Archived Human Blood Plasma and Serum Samples to Thawed Conditions." Molecular & Cellular Proteomics 18, no. 10 (July 19, 2019): 2121–37. http://dx.doi.org/10.1074/mcp.tir119.001659.

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Exposure of blood plasma/serum (P/S) to thawed conditions (> −30 °C) can produce biomolecular changes that skew measurements of biomarkers within archived patient samples, potentially rendering them unfit for molecular analysis. Because freeze-thaw histories are often poorly documented, objective methods for assessing molecular fitness before analysis are needed. We report a 10-μl, dilute-and-shoot, intact-protein mass spectrometric assay of albumin proteoforms called “ΔS-Cys-Albumin” that quantifies cumulative exposure of archived P/S samples to thawed conditions. The relative abundance of S-cysteinylated (oxidized) albumin in P/S increases inexorably but to a maximum value under 100% when samples are exposed to temperatures > −30 °C. The difference in the relative abundance of S-cysteinylated albumin (S-Cys-Alb) before and after an intentional incubation period that drives this proteoform to its maximum level is denoted as ΔS-Cys-Albumin. ΔS-Cys-Albumin in fully expired samples is zero. The range (mean ± 95% CI) observed for ΔS-Cys-Albumin in fresh cardiac patient P/S (n = 97) was, for plasma 12–29% (20.9 ± 0.75%) and for serum 10–24% (15.5 ± 0.64%). The multireaction rate law that governs S-Cys-Alb formation in P/S was determined and shown to predict the rate of formation of S-Cys-Alb in plasma and serum samples—a step that enables back-calculation of the time at which unknown P/S specimens have been exposed to room temperature. A blind challenge demonstrated that ΔS-Cys-Albumin can detect exposure of groups (n = 6 each) of P/S samples to 23 °C for 2 h, 4 °C for 16 h, or −20 °C for 24 h—and exposure of individual specimens for modestly increased times. An unplanned case study of nominally pristine serum samples collected under NIH-sponsorship demonstrated that empirical evidence is required to ensure accurate knowledge of archived P/S biospecimen storage history.

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Piontek, Aleksandra, Elwira Bisz, Błażej Dziuk, Roman Szostak, and Michal Szostak. "Structures and energetic properties of 4-halobenzamides." Acta Crystallographica Section C Structural Chemistry 74, no. 11 (October 23, 2018): 1395–402. http://dx.doi.org/10.1107/s2053229618013463.

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The amide bond represents one of the most fundamental functional groups in chemistry. The properties of amides are defined by amidic resonance (nN→π*C=O conjugation), which enforces planarity of the six atoms comprising the amide bond. Despite the importance of 4-halo-substituted benzamides in organic synthesis, molecular interactions and medicinal chemistry, the effect of 4-halo-substitution on the properties of the amide bond in N,N-disubstituted benzamides has not been studied. Herein, we report the crystal structures and energetic properties of a full series of 4-halobenzamides. The structures of four 4-halobenzamides (halo = iodo, bromo, chloro and fluoro) in the N-morpholinyl series have been determined, namely 4-[(4-halophenyl)carbonyl]morpholine, C11H12 XNO2, for halo = iodo (X = I), bromo (X = Br), chloro (X = Cl) and fluoro (X = F). Computations have been used to determine the effect of halogen substitution on the structures and resonance energies. 4-Iodo-N-morpholinylbenzamide crystallized with a significant distortion of the amide bond (τ + χN = 33°). The present study supports the correlation between the Ar—C(O) axis twist angle and the twist angle of the amide N—C(O) bond. Comparison of resonance energies in synthetically valuable N-morpholinyl and N-piperidinyl amides demonstrates that the O atom of the morpholinyl ring has a negligible effect on amidic resonance in the series.

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Tsai, Yueh-Ting, Shung-Te Kao, and Chin-Yi Cheng. "Medicinal Herbs and Their Derived Ingredients Protect against Cognitive Decline in In Vivo Models of Alzheimer’s Disease." International Journal of Molecular Sciences 23, no. 19 (September 25, 2022): 11311. http://dx.doi.org/10.3390/ijms231911311.

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Alzheimer’s disease (AD) has pathological hallmarks including amyloid beta (Aβ) plaque formation. Currently approved single-target drugs cannot effectively ameliorate AD. Medicinal herbs and their derived ingredients (MHDIs) have multitarget and multichannel properties, engendering exceptional AD treatment outcomes. This review delineates how in in vivo models MHDIs suppress Aβ deposition by downregulating β- and γ-secretase activities; inhibit oxidative stress by enhancing the antioxidant activities and reducing lipid peroxidation; prevent tau hyperphosphorylation by upregulating protein phosphatase 2A expression and downregulating glycogen synthase kinase-3β expression; reduce inflammatory mediators partly by upregulating brain-derived neurotrophic factor/extracellular signal-regulated protein kinase 1/2-mediated signaling and downregulating p38 mitogen-activated protein kinase (p38 MAPK)/c-Jun N-terminal kinase (JNK)-mediated signaling; attenuate synaptic dysfunction by increasing presynaptic protein, postsynaptic protein, and acetylcholine levels and preventing acetylcholinesterase activity; and protect against neuronal apoptosis mainly by upregulating Akt/cyclic AMP response element-binding protein/B-cell lymphoma 2 (Bcl-2)-mediated anti-apoptotic signaling and downregulating p38 MAPK/JNK/Bcl-2-associated x protein (Bax)/caspase-3-, Bax/apoptosis-inducing factor-, C/EBP homologous protein/glucose-regulated protein 78-, and autophagy-mediated apoptotic signaling. Therefore, MHDIs listed in this review protect against Aβ-induced cognitive decline by inhibiting Aβ accumulation, oxidative stress, tau hyperphosphorylation, inflammation, synaptic damage, and neuronal apoptosis in the cortex and hippocampus during the early and late AD phases.

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Journal articles on the topic 'Biomolecular and medicinal chemistry, n.e.c'

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