Articoli di riviste: "Heterocyclic compounds"

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Luna, Isadora Silva, Rayssa Marques Duarte da Cruz, Ryldene Marques Duarte da Cruz, Rodrigo Santos Aquino de Araújo e Francisco Jaime Bezerra Mendonça-Junior. "1,4-Dithiane-2,5-diol: A Versatile Synthon for the Synthesis of Sulfur-containing Heterocycles". Current Organic Synthesis 15, n. 8 (17 dicembre 2018): 1026–42. http://dx.doi.org/10.2174/1570179415666180821154551.

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Background: 1,4-Dithiane-2,5-diol (1,4-DTD) is the stable dimer of α-mercapto acetaldehyde. This commercially available ambidentade compound is characterized as having in its chemical structure one group that acts as an electrophile and another that acts as a nucleophile, this permits its use as versatile and efficient synthon in synthetic heterocycle procedures. Objective: The aim of this review is to present synthetic applications of 1,4-DTD in heterocyclic chemistry and their applicability to the synthesis of bioactive compounds. Conclusion: Gewald reactions to obtain C-4 and C-5 unsubstituted 2-amino-thiophene derivatives; sulfa- Michael/Henry and sulfa-Michael/aldol sequences to obtain polysubstituted tetrahydrothiophenes, and other heterocyclic reactions that allow synthesizing several functionalized sulfur-containing heterocycles such as thiazolidines, oxathiazinoles and thiazoles are presented and discussed. The use of such heterocyclics in subsequent reactions allows obtaining various bioactive compounds including the antiretroviral lamivudine which is one of the examples presented in this review.

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Yadav, Shailendra, Sushma Singh e Chitrasen Gupta. "A CONCISE OVERVIEW ON HETEROCYCLIC COMPOUNDS EXHIBITING PESTICIDAL ACTIVITIES". International Journal of Advanced Research 9, n. 08 (31 agosto 2021): 989–1004. http://dx.doi.org/10.21474/ijar01/13352.

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Heterocyclic compounds are numerous and diverse group of organic compounds. Heterocycles are abundantly found in nature and express various physiological properties. Heterocycles are intricately linked to all aspects of life. There are many heterocyclic compounds currently known, and the number is constantly rising owing to extensive synthetic development and their applications. Heterocyclic compounds are used significantly in a number of areas, including biochemistry and medicinal chemistry, and some others. They are predominantly synthesized in agrochemical and pharmaceutical industries due to their potential biological activities. This review article focuses on recently synthesized heterocyclic compounds and their different pesticidal activities such as antifungal, antibacterial, antiviral, nematocidal, insecticidal, acaricidal, and herbicidal.

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Bhattacharya, Somenath, Soumallya Chakraborty, Rohan Pal, Sourav Saha, Bhaskar Ghosh, Chiranjit Mandal, Dr Amitava Roy e Dr Arin Bhattacharjee. "A Comprehensive Review on Pyrazole and It’s Pharmacological Properties". International Journal for Research in Applied Science and Engineering Technology 10, n. 9 (30 settembre 2022): 1769–74. http://dx.doi.org/10.22214/ijraset.2022.46924.

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Abstract: Heterocyclic chemistry is very important aspects in organic chemistry. Heterocyclic system consists of one or more heteroatoms like nitrogen, oxygen, sulphur, etc with hydrogen atoms. The system can be classified as saturated as well as non saturated system or hydrocarbons. Another classification of this ring system is divided in some categories like three-membered, four-membered, five-membered, six-memebered, seven-membered, fused heterocyclics etc. Some compounds under this cklassification are acidic or basic in nature. Examples of heterocyclic compounds are Pyrole, Furan, Thiophene, Pyridine, Quinoline, Isoquinoline, Indole, Purine, Pyrazole, etc. Pyrazole is very important under this heterocyclic ring sysyem. Pyrazole is five membered heterocyclics. Pyrazole is basic and unsaturated in nature due to presence of double bonds in their ring structure. When two nitrogen atoms are associated with five menbered heterocyclic ring in 1,2 positions called as Pyrazole structure. It is also known as 1,2-diazole. It is present in many drugs as well as organic compounds and Pharmaceutical compounds. The review study shown that the structure, physical and chemical properties, nomenclature, synthetic approaches, biological activities of Pyrazole heterocyclic ring structure

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Palaniappan, Saravana Priya. "Pharmacological Role of Heterocyclic Compounds in the Treatment of Alzheimer’s Disease: A Review". Journal of Phytopharmacology 11, n. 4 (15 agosto 2022): 289–94. http://dx.doi.org/10.31254/phyto.2022.11412.

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Alzheimer’s disease (AD) is a multifactorial neurological disease that mainly affects the old age people. Neuropathologically, AD is characterized by low level of acetylcholine, loss of synapses and neurons in certain brain regions, accumulation of extracellular amyloid beta peptide (Aβ) and phosphorylation of intracellular tau protein. Patients with AD are characterized by various symptoms such as memory deficits, depression, cognitive dysfunction and difficult to perform daily activities. Currently available drugs for the treatment of AD are used to treat symptomatic relief at an early stage, however the prolonged usage of the drugs may cause adverse side effects. To overcome this, development of drugs produced from natural products is considered as one of the promising alternatives for the treatment of AD. Among that heterocyclic compound play a major role in the development of therapeutic drugs against various disorders. An organic compound which is cyclic or non-cyclic consists of one or more atoms in their ring structure are known as heterocyclic compounds. These heterocyclic compounds occur both in natural and synthetic form and play a major role in the metabolism of all living cells. Most of the organic compounds used as drugs have a heterocyclic core in their skeleton. Nitrogenous bases such as purines and pyrimidines present in DNA, chlorophyll, vitamins contain heterocycle in their structure. Other compounds containing heterocycles are proline, morphine, furan, vinblastine, cephalosporin, penicillin etc. This review summarizes the nomenclature, classification, and the role of heterocyclic compounds in the treatment of Alzheimer's disease.

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Shaikh, Ansar R., Mazahar Farooqui, R. H. Satpute e Syed Abed. "Overview on Nitrogen containing compounds and their assessment based on ‘International Regulatory Standards’". Journal of Drug Delivery and Therapeutics 8, n. 6-s (21 dicembre 2018): 424–28. http://dx.doi.org/10.22270/jddt.v8i6-s.2156.

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Heterocyclic compounds have a role in most fields of sciences such as medicinal chemistry, biochemistry also another area of sciences. More than 90% of new drugscontain heterocycles and the interface between chemistry and biology, at which so much new scientific insight, discovery and application is taking place is crossed by heterocyclic compounds. Compounds derived from heterocyclic rings in pharmacy, medicine, agriculture, plastic, polymer and other fields.Most active heterocycles that have shown considerable biological actions as antifungal, anti-inflammatory, antibacterial, anticonvulsant, antiallergic, herbicidal, anticancer activity. There is always a strong need for new and efficient processes in synthesizing of new Heterocycles.Alum have been used as a novel catalyst in the synthesis of Schiff’s bases. Synthesized Schiff’s bases are free from use of ICH class 1 and Class 2 solvents and also free from structural alerts genotoxic impurities. This review highlights on various aspects of heterocyclic compounds with its biological activity & regulatory assessment based on the ‘International Regulatory Standards’. Keywords: Heterocycles. Nitrogen containing compounds Biological activity, History, Regulatory assessment, International Regulatory Standards

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Adak, Laksmikanta, e Tubai Ghosh. "Recent Progress in Iron-Catalyzed Reactions Towards the Synthesis of Bioactive Five- and Six-Membered Heterocycles". Current Organic Chemistry 24, n. 22 (18 dicembre 2020): 2634–64. http://dx.doi.org/10.2174/1385272824999200714102103.

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Heterocyclic compounds are the largely diverse organic molecules and find prevalent applications in the fine chemical industry, medicinal chemistry and agricultural science. They are also among the most commonly bearing frameworks in numerous drugs and pharmaceutical substances. Therefore, the development of convenient, efficient and environmentally benign methods to produce various types of heterocyclic compounds is an attractive area of research. For the synthesis and functionalization of heterocycles, enormous achievements have been attributed over the past decades. Recently, ironcatalyzed reactions have accomplished a noteworthy development in the synthesis of heterocycles. This review highlights some remarkable achievements in the iron-catalyzed synthesis of heterocyclic compounds published in the last five years.

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Olšovská, Jana, Karel Štěrba, Martin Slabý e Tomáš Vrzal. "Novel method for determination of heterocyclic compounds and their impact in brewing technology". KVASNY PRUMYSL 67, n. 2 (15 aprile 2021): 417–27. http://dx.doi.org/10.18832/kp2021.67.417.

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A new simultaneous method for determination of 16 heterocyclic compounds using SPE sample preparation and GC-MS determination was developed regarding increasing interest of the role of sensory active compounds in beer. LiChrolut® EN SPE columns proved to be optimal for both, a mixture of analytes with a different polarity and such complicated matrix as beer. Recoveries of individual analytes are about 100% except for three compounds (2-methylpyridine about 30%, maltol and furaneol about 50%); repeatability, uncertainty and LOQ are satisfactory for the method application. The method was used for monitoring of heterocyclic compounds formation during roasting, mashing, hop boiling and fermentation. To summarize, during roasting of malt, the concentration of oxygen heterocycle compounds (OHC) increases more rapidly in comparison with nitrogen heterocycles compounds (NHC) till a critical point where OHC starts to decrease and NHC starts to be formed sharper (with the exception of 2-acetylpyrrole which is similar to OHC). Finally, the total concentration of NHC during fermentation rapidly decreases whilst the OHC concentration is influenced by many factors, e.g., fermentation conditions and yeast strain.

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Shekarkhand, Marzieh, Karim Zare, Majid Monajjemi, Elham Tazikeh-Lemeski e Masoumeh Sayadian. "Computational study of heterocyclic anticancer compounds through nbo method". Nexo Revista Científica 35, n. 01 (6 aprile 2022): 367–81. http://dx.doi.org/10.5377/nexo.v35i01.13982.

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In the present study NBO method contain the HOMO and the LUMO energies are calculated for 10 different heterocycles anticancer drug using B3LYP/6-31G(d,p). Frontier molecular orbitals (HOMO and LUMO) and Molecular Electrostatic Potential map of the compound was produced by using the π stacking of structures and anticancer activity of molecules. The NBO analysis was suggested that the molecular system contains π- π interaction, strong conjugative interactions and the molecule become more polarized owing to the movement of π-electron cloud from donor to acceptor. NBO, HOMO and LUMO energies, were investigated and Anticancer activity of Aromatic Heterocyclic compounds was investigated by NBO study and result was compared with our previous study about NICS and S-NICS of these 10 anticancer drug. the HOMO/LUMO gap of the heterocycle anticancer drug is significantly different from each other. The NBO method is used in both symmetric and asymmetric molecules and provides accurate information on the aromatics of the compound, especially the heterocyclic rings. It also provides accurate information in protected areas. Molecule 8 has the highest amount of HOMO and therefore aromaticity among the studied compounds which confirms the result of molecular orbital examination.

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Murarka, Sandip, e Andrey Antonchick. "Metal-Catalyzed Oxidative Coupling of Ketones and Ketone Enolates". Synthesis 50, n. 11 (3 maggio 2018): 2150–62. http://dx.doi.org/10.1055/s-0037-1609715.

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Recent years have witnessed a significant advancement in the field of radical oxidative coupling of ketones towards the synthesis of highly useful synthetic building blocks, such as 1,4-dicarbonyl compounds, and biologically important heterocyclic and carbocyclic compounds. Besides oxidative homo- and cross-coupling of enolates, other powerful methods involving direct C(sp3)–H functionalizations of ketones have emerged towards the synthesis of 1,4-dicarbonyl compounds. Moreover, direct α-C–H functionalization of ketones has also allowed an efficient access to carbocycles and heterocycles. This review summarizes all these developments made since 2008 in the field of metal-catalyzed/promoted radical-mediated functionalization of ketones at the α-position.1 Introduction2 Synthesis of 1,4-Dicarbonyl Compounds3 Synthesis of Heterocyclic Scaffolds4 Synthesis of Carbocyclic Scaffolds5 Conclusion

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Dudhe, Anshu R., Sachinkumar D. Gunjal, Sampath AG, Sushama Rawat e YY Nandurkar. "An Overview on Nitrogen-containing Heterocyclic Compounds as Anticancer Agents". INTERNATIONAL JOURNAL OF PHARMACEUTICAL QUALITY ASSURANCE 14, n. 04 (25 dicembre 2023): 1296–301. http://dx.doi.org/10.25258/ijpqa.14.4.72.

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Cancer accounts for nearly 10 million losses each year. Among the most prevalent cancer types are breast, lung, colon, rectum, and prostate cancers. Astonishingly, around one-third of cancer-related deaths can be attributed to factors such as tobacco usage, a high body mass index (BMI), alcohol consumption, restricted ingestion of fruits and vegetables, and inadequate bodily bustle. In the field of pharmaceuticals, heteroatoms and heterocyclic compounds frequently assume crucial roles and serve as common structural components in numerous active natural products. Statistically, the majority of biologically active compounds is either heterocycles themselves or incorporate a heterocyclic element, with nitrogen-containing heterocycles being the most prevalent structural framework in these intricate molecules. These findings underscore the significant and ever-evolving role of heterocycles in contemporary drug blueprints and drug sighting practice. The chief hub of the review was to explore the documented anti-cancer properties of nitrogen-containing heterocyclic compounds, as reported in current scientific literature.

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Moskalik, Mikhail Yu. "Monofluoromethylation of N-Heterocyclic Compounds". International Journal of Molecular Sciences 24, n. 24 (18 dicembre 2023): 17593. http://dx.doi.org/10.3390/ijms242417593.

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The review focuses on recent advances in the methodologies for the formation or introduction of the CH2F moiety in N-heterocyclic substrates over the past 5 years. The monofluoromethyl group is one of the most versatile fluorinated groups used to modify the properties of molecules in synthetic medical chemistry. The review summarizes two strategies for the monofluoromethylation of N-containing heterocycles: direct monofluoromethylation with simple XCH2F sources (for example, ICH2F) and the assembly of N-heterocyclic structures from CH2F-containing substrates. The review describes the monofluoromethylation of pharmaceutically important three-, five- and six-membered N-heterocycles: pyrrolidines, pyrroles, indoles, imidazoles, triazoles, benzothiazoles, carbazoles, indazoles, pyrazoles, oxazoles, piperidines, morpholines, pyridines, quinolines and pyridazines. Assembling of 6-fluoromethylphenanthridine, 5-fluoromethyl-2-oxazolines, C5-monofluorinated isoxazoline N-oxides, and α-fluoromethyl-α-trifluoromethylaziridines is also shown. Fluoriodo-, fluorchloro- and fluorbromomethane, FCH2SO2Cl, monofluoromethyl(aryl)sulfoniummethylides, monofluoromethyl sulfides, (fluoromethyl)triphenylphosphonium iodide and 2-fluoroacetic acid are the main fluoromethylating reagents in recent works. The replacement of atoms and entire functional groups with a fluorine atom(s) leads to a change and often improvement in activity, chemical or biostability, and pharmacokinetic properties. The monofluoromethyl group is a bioisoster of -CH3, -CH2OH, -CH2NH2, -CH2CH3, -CH2NO2 and -CH2SH moieties. Bioisosteric replacement with the CH2F group is both an interesting task for organic synthesis and a pathway to modify drugs, agrochemicals and useful intermediates.

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Huang, Pengfei, Pan Wang, Shengchun Wang, Shan Tang e Aiwen Lei. "Electrochemical oxidative [4 + 2] annulation of tertiary anilines and alkenes for the synthesis of tetrahydroquinolines". Green Chemistry 20, n. 21 (2018): 4870–74. http://dx.doi.org/10.1039/c8gc02463d.

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Ābele, E., R. Ābele, Ļ. Golomba, J. Višņevska, T. Beresņeva e K. Rubina. "Oximes of Seven-Membered Heterocyclic Compounds Containing One Heteroatom". Latvian Journal of Chemistry 50, n. 3-4 (1 gennaio 2011): 205–22. http://dx.doi.org/10.2478/v10161-011-0071-7.

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Oximes of Seven-Membered Heterocyclic Compounds Containing One Heteroatom Literature data on the synthesis and structure of azepane, oxepane and thiepane oximes were reviewed. Synthesis of novel heterocycles from oximes of seven-membered heterocycles containing one heteroatom were described. Biological activity of oximes of seven-membered heterocycles with one heteroatom was also reviewed.

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Ābele, E. "Oximes of Seven-Membered Heterocyclic Compounds Containing Two Heteroatoms". Latvian Journal of Chemistry 51, n. 1-2 (1 gennaio 2012): 83–92. http://dx.doi.org/10.2478/v10161-012-0005-z.

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Oximes of Seven-Membered Heterocyclic Compounds Containing Two Heteroatoms Literature data concerning the synthesis and structure of diazepane, oxazepane and thiazepane oximes were reviewed. Synthesis of novel heterocycles from the oximes of seven-membered heterocycles containing two heteroatoms was described. Biological activity of oximes of seven-membered heterocycles with two heteroatoms was also reviewed.

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Mohareb, Rafat, e Hanaa Hana. "Synthesis of progesterone heterocyclic derivatives of potential antimicrobial activity". Acta Pharmaceutica 58, n. 1 (1 marzo 2008): 29–42. http://dx.doi.org/10.2478/v10007-007-0043-3.

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Synthesis of progesterone heterocyclic derivatives of potential antimicrobial activityThe aim of this work was to synthesize steroidal heterocycles and to elucidate the potential role of these compounds as antimicrobial agents. The synthesis of steroidal heterocycles containing the pyrazole, isoxazole, thiazole, pyrane, pyridine, pyridazine, or benzopyrane ring attached to the pregnene nucleus is reported. Progesterone (1) reacts with dimethyl formamide dimethyl acetal to form enamine2. Heterocyclization of2with hydrazines, hydroxylamine, glycine, ethyl acetoacetate or cyanomethylene afforded novel steroidal heterocyclic derivatives. Thein vitroantimicrobial evaluation showed that all synthesized compounds show activity against the used strains of Gram positive bacteria and fungi.

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Harith M. Al-ajely. "Synthesis and pharmaceutical applications of Oxazine compounds derived from Pyronic, Salicylic, Antharanilic acids and Phenols". International Journal of Science and Research Archive 2, n. 2 (30 maggio 2021): 074–86. http://dx.doi.org/10.30574/ijsra.2021.2.2.0250.

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It is well known from FDA reports that More than 75% of the heterocyclic compounds are drugs and 90 of heterocyclic compounds are cancer drugs. The nitrogen-based heterocycles occupy an exclusive position as a valuable source of therapeutic agents in medicinal chemistry. Most drugs approved by the FDA and currently available in the market are nitrogen-containing heterocyclic moieties, More over heterocyclic compounds are important class of organic chemistry due to their widely spread in nature. Also there are many route for their action and many mechanistic pathways for their preparation and different metabolic actions. This comes from the easily building or removal of any functional group within the molecules. Changing just on group cause to change the metabolic pathway of the drug action and site of attack of the desired target accordingly. This great characteristic value make them much more important in drug discovery programs of many researchers and also encouraged us and drew attentions of other researchers to develop new ways for their synthesis. As a result different pharmacological and medical applications. Oxazie compounds are sub branch of heterocyclic compounds. These compounds having two hetero atoms, Oxygen and nitrogen within their structures make them much more important toward therapeutic studies. We are here in our investigation will focus on the methodologies and the therapeutic action of the titled compounds as well as other various applications.

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Talbi, Soumaya, Mustapha Dib, Latifa Bouissane, Hafid Abderrafia, Souad Rabi e Mostafa Khouili. "Recent Progress in the Synthesis of Heterocycles based on 1,3-diketones". Current Organic Synthesis 19, n. 2 (marzo 2022): 220–45. http://dx.doi.org/10.2174/1570179418666211011141428.

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: N,O-heterocycles containing the dicarbonyl ring play a significant role in heterocyclic and therapeutic chemistry. Since the discovery of 1,3-diketones, numerous research works have been achieved regarding the synthesis and its chemical reactivity. In this review, we have described the most relevant publications involving β-diketone compounds published during the period between 2018 to date. In addition, we include the 1,3-diketones-based heterocyclic compounds prepared by various synthetic methodologies.

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Sharma, Praveen Kumar, Andleeb Amin e M. Kumar. "Synthetic Methods of Medicinally Important Heterocycles-thiazines: A Review". Open Medicinal Chemistry Journal 14, n. 1 (14 settembre 2020): 71–82. http://dx.doi.org/10.2174/1874104502014010071.

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Heterocyclic compounds containing N and S atoms have unique properties so that they can be used as potential reactive materials in pharmacokinetic systems. In medicinal chemistry, the therapeutic applications of nitrogen sulphur heterocycles are well known. Especially, Thiazines attract the attention of chemists due to their great bioactive behavior. The present study is a review of the work carried out by the research community for the synthesis of novel, effective, medicinally important heterocyclic compounds-thiazines.

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Shah, Pranay, R. I. Patel e P. J. Vyas. "Preparation and Biological Screening of Novel Heterocyclic Compounds". International Journal of Trend in Scientific Research and Development Volume-3, Issue-3 (30 aprile 2019): 632–36. http://dx.doi.org/10.31142/ijtsrd22815.

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Soni, Vatsala, Meenakshi Sharma, Vandana Singh, Vaishali Soni e Kishore D. "Comprehensive Study of Biological Aspects of Heteroring Annelated Benzothiazoles". International Journal of Science, Engineering and Management 9, n. 6 (13 giugno 2022): 1–6. http://dx.doi.org/10.36647/ijsem/09.06.a001.

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Heterocyclic chemicals are chemical structures which include at least a single carbon molecule plus at least one other element, such as sulphur, oxygen, or nitrogen, within the ring structure. Benzothiazoles are discussed in terms of synthesis methodologies, structural changes, chemical reactivity, and possible pharmaceutical effectiveness. This research relied upon secondary data obtained from the sources. The qualitative method was used to provide a section of such an evaluation which looked flawless and accurate. A handy methodology strategy is used in inquiry research. Heterocyclic compounds have been widely exploited in bioorganic and medical research for medication development. Scientists are interested in such compounds because of their various physicochemical and pharmacological properties. Recognizing heterocycles is advantageous in both industrial and biological processes. Benzothiazole, a molecular heterocyclic structure, is being studied as a candidate for such creation of larger, often medicinal chemicals. It is highly durable due to its aromatic components; however, it has reactive services that offer the synthesis method. The benzothiazole ring becomes an important framework for the production of colours used throughout the identification of lanthanide metal cations in aqueous environments. This identical basic N, S heterocycle, benzothiazoles, seems to be abundant; for example, it is required essential thiamine action (vitamin B1). Thiazole compounds could also be discovered in medications such as Nosiheptide. This chemistry group is used for about simply for antibacterial purposes; its distinctive heteroring linked derivatives have attracted the curiosity of scientists due to their various biological or indeed medicinal properties.

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Hanusek, Jiří, e Vladimír Macháček. "Intramolecular base-catalyzed reactions involving interaction between benzene nitro groups and ortho carbon chains". Collection of Czechoslovak Chemical Communications 74, n. 5 (2009): 811–33. http://dx.doi.org/10.1135/cccc2008216.

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The review is focused on the understanding of processes involving chemical interaction between benzene nitro group and ortho carbon chain containing heteroatom (N, O, S) adjacent to the ring. In most cases these compounds undergo base-catalyzed cyclization to give heteroaromatic N-oxides that can be subsequently transformed to related heterocycles under the same conditions. However, in some cases, depending on substitution of the benzene ring, side chain or the base used, the formation of other compounds – both heterocyclic and non-heterocyclic such as nitroso and azoxy compounds, spiro Meisenheimer adducts – is observed. Review with 31 references.

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Orzeszko, Barbara, Tomasz Świtaj, Anna B. Jakubowska-Mućka, Witold Lasek, Andrzej Orzeszko e Zygmunt Kazimierczuk. "Tumor Necrosis Factor-α Production-Enhancing Properties of Novel Adamantylalkylthio Derivatives of Some Heterocyclic Compounds". Zeitschrift für Naturforschung B 60, n. 4 (1 aprile 2005): 471–75. http://dx.doi.org/10.1515/znb-2005-0419.

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Certain adamantylated heterocycles were previously shown to enhance the secretion of tumor necrosis factor alpha (TNF-α) by murine melanoma cells that have been transduced with the gene for human TNF-α and constitutively expressed this cytokine. The stimulatory potency of those compounds depended, among other factors, on the structure of the linker between the adamantyl residue and the heterocyclic core. In the present study, a series of (1-adamantyl)alkylsulfanyl derivatives of heterocyclic compounds was prepared by alkylation of the corresponding thioheterocyles. Of the novel adamantylalkylthio compounds tested in the aforementioned cell line, 2-(2-adamantan-1-ylethylsulfanyl)- 4-methyl-pyrimidine was found to be the most active

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Chambers, Richard D., Mohammed A. Hassan, Philip R. Hoskin, Alan Kenwright, Paul Richmond e Graham Sandford. "Polyhalogenated heterocyclic compounds". Journal of Fluorine Chemistry 111, n. 2 (ottobre 2001): 135–46. http://dx.doi.org/10.1016/s0022-1139(01)00445-6.

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Benmansour, Hadjar, Richard D. Chambers, Graham Sandford, Graham McGowan, Slimane Dahaoui, Dmitrii S. Yufit e Judith A. K. Howard. "Polyhalogenated heterocyclic compounds". Journal of Fluorine Chemistry 112, n. 2 (dicembre 2001): 349–54. http://dx.doi.org/10.1016/s0022-1139(01)00534-6.

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Chambers, Richard D., Ali Khalil, Christopher B. Murray, Graham Sandford, Andrei S. Batsanov e Judith A. K. Howard. "Polyhalogenated heterocyclic compounds". Journal of Fluorine Chemistry 126, n. 7 (luglio 2005): 1002–8. http://dx.doi.org/10.1016/j.jfluchem.2005.01.018.

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Stepanenko, Sergey A., Danil M. Shivtsov, Anton P. Koskin, Igor P. Koskin, Roman G. Kukushkin, Petr M. Yeletsky e Vadim A. Yakovlev. "N-Heterocyclic Molecules as Potential Liquid Organic Hydrogen Carriers: Reaction Routes and Dehydrogenation Efficacy". Catalysts 12, n. 10 (17 ottobre 2022): 1260. http://dx.doi.org/10.3390/catal12101260.

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This study is focused on the development of liquid organic hydrogen carriers (LOHC) based on N-heterocyclic compounds. These LOHC-substrates are attractive for their lower hydrogen extraction temperature compared to cycloalkanes, which is caused by the low enthalpy of the dehydrogenation reaction of the N-heterocyclic compounds. The low hydrogen extraction temperature, as well as the low volatility of the heterocycles, provide high purity hydrogen from the reaction. Under similar reaction conditions, the comparison of the efficacy of three promising heterocycles (1-methyl-octahydroindole (8HMI), tetradecahydrophenazine and decahydroquinoline) was carried out in the presence of palladium-containing catalysts. As a result, the advantages of using catalysts supported by alumina, and the high perspectivity of the 8MHI application as a LOHC-substrate, were shown. The dehydrogenation of 8HMI in the presence of 1 wt.% Pd/Al2O3 allowed for reaching a 100% yield in hydrogen under the conditions of the standard catalytic test (1 h, 240 °C). In order to study the high reactivity of 8HMI, thermodynamic dehydrogenation reaction profiles were computationally evaluated, which showed that 8HMI was the most energetically preferred in the field of hydrogen storage from the studied heterocyclic compounds.

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Sajida. Munadi. Th.AL-Suraify e Mohammed Abdul-Mounther Othman. "Synthesis and study of spectrally diagnosed heterocyclic compound". International Journal of Research in Pharmaceutical Sciences 11, SPL4 (21 dicembre 2020): 2613–22. http://dx.doi.org/10.26452/ijrps.v11ispl4.4527.

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In general terms, medicinal chemistry manages the revelation & plan of recent remedial synthetic concoctions & its uses as meds. Throughout the most recent couple of decades, mixes bearing heterocyclic cores have gotten considerably more consideration of the scientific expert, because of their expansive chemo remedial exercises, for example, calming, anthelmintic, hostile to tubercular, against parasitic & hostile to microbial exercises. Furthermore, Heterocycles & medicines are both interred related, the human is totally dependent on drugs & most of the drugs are derived from heterocyclic compounds. Hetero cycles & their derivatives have been excited regards chemist mainly due to broad-spectrum chemical & pharmacological activities. Most of the heterocyclic compounds are naturally occurs & playing the important role of metabolism regards cells of living. There has been a bigger count of pharmacologically attracted compounds of heterocyclic, several of which have been under continues clinical utilization. This paper presented a detailed study of synthesis which is spectrally detected Heterocyclic compounds, in results described the antibacterial activity of (e)-s-4-(is nicotinamide)-5-(phenoxymethyl)-4h-1, 2, 4-triazol-3-yl 3-(substituted phenyl) prop-2- enethioate. (7a-7f) and antifungal activity of (e)-s-4-(isonicotinamido)-5-(phenoxymethyl)-4h-1, 2, 4-triazol-3-yl 3-(substituted phenyl) prop-2-enethioate. (7a-7f), antitubercular activity of against mycobacterium tuberculosis h37rv presented the scope of this paper.

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28

Monier, Mohamed, Doaa Abdel-Latif, Ahmed El-Mekabaty, Başak D. Mert e Khaled M. Elattar. "Advances in the Chemistry of 6-6 Bicyclic Systems: Chemistry of Pyrido[3,4- d]pyrimidines". Current Organic Synthesis 16, n. 6 (26 novembre 2019): 812–54. http://dx.doi.org/10.2174/1570179416666190704113647.

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Abstract (sommario):

The aim of this work is to discuss the chemistry of pyrido[3,4-d]pyrimidines as one of the most important heterocyclic compounds with remarkable synthetic, biological and medical applications. In this overview, the chemistry of heterocyclic compounds incorporated the pyrido[3,4-d]pyrimidine scaffold as demonstrated by chemical reactions and different preparation processes. The anticipated compounds were synthesized from pyridine or pyrimidine compounds and a description of the reactivity of substituents attached to ring carbon and nitrogen atoms is discussed. On the other hand, the synthesis and reactions of fused heterocycles incorporated pyrido[3,4-d]pyrimidine scaffold is described. The diamine analogs included pyrido[3,4-d]pyrimidine core were reported as tyrosine kinase inhibitors. The chemical reactions of certain unexpected and chemically substantial compounds have been discussed.

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29

Cui, Hai-Lei. "Recent Advances in DMSO-Based Direct Synthesis of Heterocycles". Molecules 27, n. 23 (2 dicembre 2022): 8480. http://dx.doi.org/10.3390/molecules27238480.

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Abstract (sommario):

Besides serving as a low-toxicity, inexpensive and easily accessible solvent, dimethyl sulfoxide (DMSO) has also been extensively used as a versatile reagent for the synthesis of functionalized molecules. Dimethyl sulfoxide can not only be utilized as a carbon source, a sulfur source and an oxygen source, but also be employed as a crucial oxidant enabling various transformations. The past decade has witnessed a large number of impressive achievements on the direct synthesis of heterocycles as well as modifications of heterocyclic compounds by applying DMSO as a reagent. This review summarized the DMSO-based direct heterocycle constructions from 2012 to 2022.

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30

Drapak, І. V. "In silico screening of drug-like molecules for the treatment of cardiovascular diseases on the basis of five-membered privileged heterocycles". Farmatsevtychnyi zhurnal, n. 4 (10 settembre 2019): 61–72. http://dx.doi.org/10.32352/0367-3057.4.19.07.

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Abstract (sommario):

Among various heterocyclic systems, the derivatives of five-membered heterocycles are of special interest. Most of the above mentioned heterocycles are treatred as so-called privileged structures in modern medicinal chemistry. In silico screening among five-membered heterocycles of molecules for the treatment of cardiovascular diseases is actual. The aim of the work was the search for synthetic drug-like molecules based on functionalized five-membered heterocycles and related heterocyclic systems as an element of the theoretical platform for rational design of compounds acting on the cardiovascular system, and prediction of their possible mechanism of action. The objects of the study were derivatives of uncondensed and condensed five-membered heterocycles. In the work, in silico approaches were applied using the programs: Hyper-Chem, PASS, AutoDock, PROTOX. Based on the previous studies, focused sub-libraries of small synthetic drug-like molecules based on functionalized five-membered heterocycles and related heterocyclic systems have been selected. The compounds were divided on 12 groups. The optimization of the compound structures, the drug-like parameters calculation were carried out. The activity prediction, the acute toxicity level and docking studies to probable bio-targets which are related with cardiovascular drug mechanism of action have been carried out. It was shown that thiazole and thiadiazole based compounds possessed the highest calculated affinity levels to selected bio-targets. This is consistent with PASS-based prediction data. Diverse functionalized derivatives of five-membered heterocycles (thiazole, thiazolidine, thiadiazole, pyrazole, thiophene, triazole) and related fused heterocycles have been grouped in focused sub-libraries of compounds. it has been established that thiazole and thiadiazole based compounds are promising objects for directed synthesis and further modification as potential cardiovascular agents based on the prediction of biological activity, the calculation of affinity to potent bio-targets, and the prediction of the drug-like features and acute toxicity level. The prognostic values of the parameters of the above mentioned groups of compounds may be used as the element of theoretical platform for the search and de novo design of potential drugs for the treatment of cardiovascular diseases.

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31

Biswas, Titas. "Synthesis of heterocyclic compounds using ring-closing enyne metathesis reaction". INTERNATIONAL JOURNAL OF EXPERIMENTAL RESEARCH AND REVIEW 22 (30 agosto 2020): 20–29. http://dx.doi.org/10.52756/ijerr.2020.v22.003.

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Abstract (sommario):

Ring-closing enyne metathesis reaction has emerged as an elegant tool in organic synthesis for the creation of molecular complexity and used to prepare diverse heterocycles. In this mini review, I discuss that various linearly and angularly architecture heterocyclic compounds may be prepared using RCEM as key steps.

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32

Depa, Navaneetha, e Harikrishna Erothu. "SYNTHESIS AND BIOLOGICAL ACTIVE COMPOUNDS OF NITROGEN-CONTAINING HETEROCYCLIC COMPOUNDS: A REVIEW". RASAYAN Journal of Chemistry 15, n. 03 (2022): 1709–17. http://dx.doi.org/10.31788/rjc.2022.1536924.

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Abstract (sommario):

Heterocyclic chemistry has a broad spectrum of applications in our day-to-day life. Heterocyclic compounds contain hetero atoms like oxygen, nitrogen, and sulphur in their structure. Among these atoms, a wide variety of heterocyclic moieties with nitrogen as hetero atoms have considerable physiological properties and useful medical applications. Nitrogen-containing heterocyclic compounds are considered a significant category due to their broad therapeutic applications like antibacterial, antimalarial, anticancer, antifungal, anti-HIV, anti-inflammatory, etc., this review article focuses on novel moieties of indole, pyrazole, and triazole compounds and its biological importance

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33

Nehra, Bhupender, Bijo Mathew e Pooja A. Chawla. "A Medicinal Chemist’s Perspective Towards Structure Activity Relationship of Heterocycle Based Anticancer Agents". Current Topics in Medicinal Chemistry 22, n. 6 (marzo 2022): 493–528. http://dx.doi.org/10.2174/1568026622666220111142617.

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Abstract (sommario):

Aim: This paper aims to describe the structure activity relationship of heterocyclic deriva-tives with multi-targeted anticancer activity. Objectives: With the following goals in mind, this review tries to describe significant recent advances in the medicinal chemistry of heterocycle-based compounds: (1) To shed light on recent literature focused on heterocyclic derivatives' anticancer potential; (2) To discuss recent advances in the medic-inal chemistry of heterocyclic derivatives, as well as their biological implications for cancer eradica-tion; (3) To summarise the comprehensive correlation of structure activity relationship (SAR) with pharmacological outcomes in cancer therapy. Background: Cancer remains one of the major serious health issues in the world today. Cancer is a complex disease in which improperly altered cells proliferate at an uncontrolled, rapid, and severe rate. Variables such as poor dietary habits, high stress, age, and smoking, can all contribute to the development of cancer. Cancer can affect almost any organ or tissue, although the brain, breast, liver, and colon are the most frequently affected organs. For several years, surgical operations and irradia-tion have been in use along with chemotherapy as a primary treatment of cancer, but still, effective treatment of cancer remains a huge challenge. Chemotherapy is now considered one of the most ef-fective strategies to eradicate cancer, although it has been shown to have a number of cytotoxic and unfavourable effects on normal cells. Despite all of these cancer treatments, there are several other targets for anticancer drugs. Cancer can be effectively eradicated by focusing on these targets, includ-ing cell-specific and receptor-specific targets such as tyrosine kinase receptors (TKIs). Heterocyclic scaffolds also have a variety of applications in drug development and are a common moiety in the pharmaceutical, agrochemical, and textile industries. Methods: The association between structural activity relationship data of many powerful compounds and their anticancer potential in vitro and in vivo has been studied. SAR of powerful heterocyclic compounds can also be generated using molecular docking simulations, as reported in literature. Conclusions: Heterocycles have a wide range of applications, from natural compounds to synthesised derivatives with powerful anticancer properties. To avoid cytotoxicity or unfavourable effects on normal mammalian cells due to a lack of selectivity towards the target site, as well as to reduce the occurrence of drug resistance, safer anticancer lead compounds with higher potency and lower cyto-toxicity are needed. This review emphasizes on design and development of heterocyclic lead com-pounds with promising anticancer potential.

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34

Panda, Siva S., Marian N. Aziz, Jacek Stawinski e Adel S. Girgis. "Azomethine Ylides—Versatile Synthons for Pyrrolidinyl-Heterocyclic Compounds". Molecules 28, n. 2 (9 gennaio 2023): 668. http://dx.doi.org/10.3390/molecules28020668.

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Abstract (sommario):

Azomethine ylides are nitrogen-based three-atom components commonly used in [3+2]-cycloaddition reactions with various unsaturated 2π-electron components. These reactions are highly regio- and stereoselective and have attracted the attention of organic chemists with respect to the construction of diverse heterocycles potentially bearing four new contiguous stereogenic centers. This review article complies the most important [3+2]-cycloaddition reactions of azomethine ylides with various olefinic, unsaturated 2π-electron components (acyclic, alicyclic, heterocyclic, and exocyclic ones) reported over the past two decades.

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35

Francke, Robert. "Recent advances in the electrochemical construction of heterocycles". Beilstein Journal of Organic Chemistry 10 (3 dicembre 2014): 2858–73. http://dx.doi.org/10.3762/bjoc.10.303.

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Abstract (sommario):

Due to the fact that the major portion of pharmaceuticals and agrochemicals contains heterocyclic units and since the overall number of commercially used heterocyclic compounds is steadily growing, heterocyclic chemistry remains in the focus of the synthetic community. Enormous efforts have been made in the last decades in order to render the production of such compounds more selective and efficient. However, most of the conventional methods for the construction of heterocyclic cores still involve the use of strong acids or bases, the operation at elevated temperatures and/or the use of expensive catalysts and reagents. In this regard, electrosynthesis can provide a milder and more environmentally benign alternative. In fact, numerous examples for the electrochemical construction of heterocycles have been reported in recent years. These cases demonstrate that ring formation can be achieved efficiently under ambient conditions without the use of additional reagents. In order to account for the recent developments in this field, a selection of representative reactions is presented and discussed in this review.

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36

Slivka, Mikhailo, e Mikhailo Onysko. "The Use of Electrophilic Cyclization for the Preparation of Condensed Heterocycles". Synthesis 53, n. 19 (19 maggio 2021): 3497–512. http://dx.doi.org/10.1055/s-0040-1706036.

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Abstract (sommario):

AbstractCondensed heterocycles are well-known for their excellent biological effects and they are undeniably important compounds in organic chemistry. Electrophilic cyclization reactions are widely used for the synthesis of mono-heterocyclic compounds. This review highlights the utility of electrophilic cyclization reactions as an effective generic tool for the synthesis of various condensed heterocycles containing functional groups that are able to undergo further chemical transformations, such as nucleophilic substitution, elimination, re-cyclization, cleavage, etc. This review describes the reactions of unsaturated derivatives of different heterocycles with various electrophilic agents (halogens, arylsulfanyl chlorides, mineral acids) resulting in annulation of an additional partially saturated heterocycle. The electrophilic reaction conditions, plausible mechanisms and the use of such transformations in organic synthesis are also discussed. The review mainly focuses on research published since 2002 in order to establish the current state of the art in this area. 1 Introduction2 Electrophilic Cyclization Pathways Involving a Nitrogen Nucleophilic Center3 Electrophilic Cyclization Pathways Involving a Chalcogen Nucleophilic Center3.1 Sulfur Centers3.2 Oxygen Centers3.3 Selenium Centers4 Strategies and Mechanisms5 Conclusion

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37

Su, Biyun, Yifan Hou, Li Wang, Xiaoteng Li, Dandan Pan, Tingyu Yan, Ao Zhang, Faida Paison e Liqing Ding. "The Syntheses, Characterization and Crystal Structures of a Series of Heterocyclic β-Diketones and Their Isoxazole Compounds". Current Organic Synthesis 16, n. 8 (20 gennaio 2020): 1174–84. http://dx.doi.org/10.2174/1570179416666191022113022.

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Abstract (sommario):

Background: In the field of coordination chemistry, the introduction of heterocyclic substituents into the structure of β-diketone enables ligand to produce multiple coordination sites. The adoption of small steric oxime group into the structure of heterocyclic β-diketone by Schiff-base condensation will further increase coordination sites and facilitate the generation of polynuclear structures. Objective: A series of β-diketones (2a-2c) containing different heterocycles such as pyridine, thiophene and furan and their corresponding isoxazole compounds (3a-3c) were synthesized. Materials and Methods: The Claisen condensations were investigated in a solvent-free rheological phase system at room temperature to obtain heterocyclic β-diketones 2a-2c, which further reacted with hydroxylamine hydrochloride to obtain heterocyclic isoxazoles 3a-3c. All these compounds were well characterized by EA, IR, 1H NMR and X-ray crystal diffraction to confirm the structures. Synthetic mechanisms of compounds and the effects of different heterocycles on reactivity were discussed deeply. Result: 1H NMR indicated that these β-diketones do not exist as a total diketonic form but an equilibration between diketone and enol forms in CDCl3 solvent, in which the enol form accounts for 98.0% in 2a, 94.3% in 2b, 95.5% in 2c. While the crystal structures of 2a-2c showed that the reaction allows to isolate diketones in solid state. Crystal structures of 3a-3c showed that the neutral β-ketone oximes resonate and cyclize to form the target heterocyclic isoxazoles. Conclusion: SN1 nucleophilic substitution mechanism of Claisen ketoester condensation was proposed for the syntheses of 2a-2c, and SN1 single molecule nucleophilic substitution reaction mechanism was put forward for 3a-3c.

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38

Gaonkar, Santosh L., Vignesh U. Nagaraj e Swarnagowri Nayak. "A Review on Current Synthetic Strategies of Oxazines". Mini-Reviews in Organic Chemistry 16, n. 1 (19 novembre 2018): 43–58. http://dx.doi.org/10.2174/1570193x15666180531092843.

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Abstract (sommario):

In the past three decades, the heterocyclic oxazine cores have been intensely concerned. Oxazine derivatives are promising vital heterocyclic motifs. They are eminent for their synthetic potential and extensive biological properties. Oxazines are versatile intermediates for the synthesis of a variety of heterocycles and bifunctional compounds. Researchers have reported several synthetic approaches for the preparation of oxazines. This review emphasises the recent approaches for the synthesis of oxazine derivatives.

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Asif, Mohammad. "Biological Potential and Chemical Properties of Pyridine and Piperidine Fused Pyridazine Compounds: Pyridopyridazine a Versatile Nucleus". Asian Journal of Chemistry and Pharmaceutical Sciences 1, n. 1 (21 novembre 2016): 29. http://dx.doi.org/10.18311/ajcps/2016/7693.

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Abstract (sommario):

Pyridopyridazine compounds are important nitrogen atom containing heterocyclic compounds due to their pharmacological versatility. This heterocycle system characterized a structural feature for different types of bioactive compounds that exhibiting various types of biological activities which make it an attractive scaffold for the design and development of new drug molecules. This article provided information about the pharmacological properties of pyridopyridazines derivatives.

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Liu, Jia-Chun, Suresh Narva, Kang Zhou e Wen Zhang. "A Review on the Antitumor Activity of Various Nitrogenous-based Heterocyclic Compounds as NSCLC Inhibitors". Mini-Reviews in Medicinal Chemistry 19, n. 18 (29 novembre 2019): 1517–30. http://dx.doi.org/10.2174/1389557519666190312152358.

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Abstract (sommario):

At present, cancers have been causing deadly fears to humans and previously unpredictable losses to health. Especially, lung cancer is one of the most common causes of cancer-related mortality accounting for approximately 15% of all cancer cases worldwide. While Non-Small Cell Lung Carcinomas (NSCLCs) makes up to 80% of lung cancer cases. The patient compliance has been weakening because of serious drug resistance and adverse drug effects. Therefore, there is an urgent need for the development of novel structural agents to inhibit NSCLCs. Nitrogen-containing heterocyclic compounds exhibit wide range of biological properties, especially antitumor activity. We reviewed some deadly defects of clinical medicines for the lung cancer therapy and importance of nitrogen based heterocyclic derivatives against NSCLCs. Nitrogen heterocycles exhibit significant antitumor activity against NSCLCs. Nitrogen heterocyclic hybrids could be developed as multi-target-directed NSCLC inhibitors and it is believed that the review is significant for rational designs and new ideas in the development of nitrogen heterocyclic-based drugs.

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Zhu, Yannan, e You Huang. "Organocatalyzed [3+3] Annulations for the Construction of Heterocycles". Synthesis 52, n. 08 (5 febbraio 2020): 1181–202. http://dx.doi.org/10.1055/s-0039-1690810.

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Abstract (sommario):

Six-membered heterocyclic systems are widely distributed in many natural products and pharmaceuticals, and the construction of highly functionalized six-membered heterocyclic compounds is an important topic in modern organic synthesis. Organocatalyzed [3+3] annulations represents an important method for assembling a substantial variety of six-membered cycles that contain one or more heteroatoms. This review describes the development of organocatalyzed [3+3] annulations for the synthesis of six-membered heterocycles, including organocatalysis using secondary amines, tertiary amines, phosphines, chiral phosphoric acids and N-heterocyclic carbenes.1 Introduction2 Secondary Amine Catalyzed [3+3] Annulations2.1 Synthesis of Nitrogen Heterocycles2.2 Synthesis of Oxygen Heterocycles2.3 Synthesis of Sulfur Heterocycles3 Tertiary Amine Catalyzed [3+3] Annulations3.1 Catalysis through Multiple Hydrogen-Bonding Interactions3.2 Catalysis of Tertiary Amines as Lewis Bases4 Phosphine-Catalyzed [3+3] Annulations4.1 Synthesis of Nitrogen Heterocycles4.2 Synthesis of Oxygen Heterocycles4.3 Synthesis of Heterocycles Containing Two or More Heteroatoms5 Chiral Phosphoric Acid Catalyzed [3+3] Annulations5.1 Synthesis of Nitrogen Heterocycles5.2 Synthesis of Heterocycles Containing Two or More Heteroatoms6 N-Heterocyclic Carbene Catalyzed [3+3] Annulations6.1 Synthesis of Nitrogen Heterocycles6.2 Synthesis of Oxygen Heterocycles6.3 Synthesis of Heterocycles Containing Two or More Heteroatoms7 Conclusion and Outlook

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42

Deng, Yongming, Qing-Qing Cheng e Michael Doyle. "Asymmetric [3+3] Cycloaddition for Heterocycle Synthesis". Synlett 28, n. 14 (5 luglio 2017): 1695–706. http://dx.doi.org/10.1055/s-0036-1588453.

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Abstract (sommario):

Asymmetric syntheses of six-membered ring heterocycles are important research targets not only in synthetic organic chemistry but also in pharmaceuticals. The [3+3]-cycloaddition methodology is a complementary strategy to [4+2] cycloaddition for the synthesis of heterocyclic compounds. Recent progress in [3+3]-cycloaddition processes provide powerful asymmetric methodologies for the construction of six-membered ring heterocycles with one to three heteroatoms in the ring. In this account, synthetic efforts during the past five years toward the synthesis of enantioenriched six-membered ring heterocycles through asymmetric [3+3] cycloaddition are reported. Asymmetric organocatalysis uses chiral amines, thioureas, phosphoric acids, or NHC catalysis to achieve high enantiocontrol. Transition-metal catalysts used as chiral Lewis acids to activate a dipolar species is an alternative approach. The most recent advance, chiral transition-metal-catalyzed reactions of enoldiazo compounds, has contributed toward the versatile and highly selective synthesis of six-membered heterocyclic compounds.1 Introduction2 Asymmetric Formal [3+3]-Cycloaddition Reactions by Organocatalysis2.1 By Amino-Catalysis2.2 By N-Heterocyclic Carbenes2.3 By Bifunctional Tertiary Amine-thioureas2.4 By Chiral Phosphoric Acids3 Asymmetric Formal [3+3]-Cycloaddition Reactions by Transition-Metal Catalysis3.1 Copper Catalysis3.2 Other Transition-Metal Catalysis4 Asymmetric [3+3]-Cycloaddition Reactions of Enoldiazo Compounds4.1 Asymmetric [3+3]-Cycloaddition Reactions of Nitrones with Electrophilic Metallo-enolcarbene Intermediates4.2 Dearomatization in Asymmetric [3+3]-Cycloaddition Reactions of Enoldiazoacetates4.3 Asymmetric Stepwise [3+3]-Cycloaddition Reaction of Enoldiazoacetates with Hydrazones5 Summary and Outlook

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43

Bąchor, Urszula, e Marcin Mączyński. "Selected β2-, β3- and β2,3-Amino Acid Heterocyclic Derivatives and Their Biological Perspective". Molecules 26, n. 2 (15 gennaio 2021): 438. http://dx.doi.org/10.3390/molecules26020438.

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Abstract (sommario):

Heterocyclic moieties, especially five and six-membered rings containing nitrogen, oxygen or sulfur atoms, are broadly distributed in nature. Among them, synthetic and natural alike are pharmacologically active compounds and have always been at the forefront of attention due to their pharmacological properties. Heterocycles can be divided into different groups based on the presence of characteristic structural motifs. The presence of β-amino acid and heterocyclic core in one compound is very interesting; additionally, it very often plays a vital role in their biological activity. Usually, such compounds are not considered to be chemicals containing a β-amino acid motif; however, considering them as this class of compounds may open new routes of their preparation and application as new drug precursors or even drugs. The possibility of their application as nonproteinogenic amino acid residues in peptide or peptide derivatives synthesis to prepare a new class of compounds is also promising. This review highlights the actual state of knowledge about β-amino acid moiety-containing heterocycles presenting antiviral, anti-inflammatory, antibacterial compounds, anaplastic lymphoma kinase (ALK) inhibitors, as well as agonist and antagonists of the receptors.

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Sparr, Christof, e Christian Fischer. "Configurationally Stable Atropisomeric Acridinium Fluorophores". Synlett 29, n. 16 (3 agosto 2018): 2176–80. http://dx.doi.org/10.1055/s-0037-1610233.

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Abstract (sommario):

Arylated heterocyclic fluorophores are particularly useful scaffolds for numerous applications, such as bioimaging or synthetic photochemistry. While variation of the substitution pattern at the heterocycle and aryl groups allows dye modulation, the bond rotational barriers are also strongly affected. Unsymmetrically substituted ring systems of rotationally restricted arylated heterocycles therefore lead to configurationally stable atropisomeric fluorophores. Herein, we describe these characteristics by determining the properties and configurational stability of atropisomeric, tri-ortho-substituted naphthyl-acridinium fluorophores. A significant barrier to rotation of >120 kJ mol–1 was measured, which renders these dyes and related compounds distinct atropisomers with stereoisomer-specific properties over a broad temperature range.

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45

Pang, Shaofeng, Yujing Zhang, Qiong Su, Fangfang Liu, Xin Xie, Zhiying Duan, Feng Zhou, Ping Zhang e Yanbin Wang. "Superhydrophobic nickel/carbon core–shell nanocomposites for the hydrogen transfer reactions of nitrobenzene and N-heterocycles". Green Chemistry 22, n. 6 (2020): 1996–2010. http://dx.doi.org/10.1039/c9gc04358f.

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Abstract (sommario):

In this work, catalytic hydrogen transfer as an effective, green, convenient and economical strategy is for the first time used to synthesize anilines and N-heterocyclic aromatic compounds from nitrobenzene and N-heterocycles in one step.

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46

Abbas, Sumayah Saadi, Azhar Mahdi Jasim, Tayseer Hamid Shakir e Iman Saadi Abbas. "Anticancer Activities of Some Heterocyclic Compounds Containing an Oxygen Atom: A Review". Al-Rafidain Journal of Medical Sciences ( ISSN: 2789-3219 ) 4 (27 aprile 2023): 60–67. http://dx.doi.org/10.54133/ajms.v4i.109.

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Abstract (sommario):

The purpose of this study is to underline the progression and development of research regarding oxygen-containing heterocycles as well as the contribution that some oxygen-containing heterocycles have made as anticancer medicines. A series of publications about the antitumor effects of derivatives of heterocyclic compounds containing an oxygen atom, such as furan, benzofuran, oxazole, benzoxazole, and oxadiazole, were evaluated, and their anticancer activities showed encouraging results when compared to those of established standard treatments.

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47

Egbujor, Melford C., Paolo Tucci, Ugomma C. Onyeije, Chigbundu N. Emeruwa e Luciano Saso. "NRF2 Activation by Nitrogen Heterocycles: A Review". Molecules 28, n. 6 (18 marzo 2023): 2751. http://dx.doi.org/10.3390/molecules28062751.

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Abstract (sommario):

Several nitrogen heterocyclic analogues have been applied to clinical practice, and about 75% of drugs approved by the FDA contain at least a heterocyclic moiety. Thus, nitrogen heterocycles are beneficial scaffolds that occupy a central position in the development of new drugs. The fact that certain nitrogen heterocyclic compounds significantly activate the NRF2/ARE signaling pathway and upregulate the expression of NRF2-dependent genes, especially HO-1 and NQO1, underscores the need to study the roles and pharmacological effects of N-based heterocyclic moieties in NRF2 activation. Furthermore, nitrogen heterocycles exhibit significant antioxidant and anti-inflammatory activities. NRF2-activating molecules have been of tremendous research interest in recent times due to their therapeutic roles in neuroinflammation and oxidative stress-mediated diseases. A comprehensive review of the NRF2-inducing activities of N-based heterocycles and their derivatives will broaden their therapeutic prospects in a wide range of diseases. Thus, the present review, as the first of its kind, provides an overview of the roles and effects of nitrogen heterocyclic moieties in the activation of the NRF2 signaling pathway underpinning their antioxidant and anti-inflammatory actions in several diseases, their pharmacological properties and structural–activity relationship are also discussed with the aim of making new discoveries that will stimulate innovative research in this area.

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S. Farhan, Mohammed, e Kawkab Y. Saour. "Synthesis of some Novel Nitrogenous Heterocyclic Compounds with Expected Biological Activity as Antimicrobial and Cytotoxic Agents". Iraqi Journal of Pharmaceutical Sciences ( P-ISSN 1683 - 3597 E-ISSN 2521 - 3512) 24, n. 1 (27 marzo 2017): 49–58. http://dx.doi.org/10.31351/vol24iss1pp49-58.

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Abstract (sommario):

This study includes synthesis of some nitrogenous heterocyclic compounds linked to amino acid esters or heterocyclic amines that may have a potential activity as antimicrobial and/or cytotoxic. Quinolines are an important group of organic compounds that possess useful biological activity as antibacterial, antifungal and antitumor .8-Hydroxyquinoline (8-HQ) and numerous of its derivatives exhibit potent activities against fungi and bacteria which make them good candidates for the treatment of many parasitic and microbial infection diseases. These pharmacological properties of quinolones aroused our interest in synthesizing several new compounds featuring heterocyclic rings of the quinoline derivatives linked to amino acid ester or heterocyclic amine with the aim of obtaining a pharmacologically active compounds.O-alkylation has been done on( 8-hydroxyquinoline ) to get (O-alkylated ester) derivatives which are deesterfied to get acetic acid derivatives, then coupled with amino acid that have protected carboxyl group (amino acid esters) or heterocyclic amine by using conventional solution method for peptide synthesis as a coupling method. The proposed analogues were successfully synthesized and the processing of the reactions confirmed by TLC ,the synthesized analogues with the proposed structures as they were characterized and proved by melting point, infrared spectroscopy (IR) and elemental microanalysis. The tested analogues showed cytotoxic activity on the HEp-2 cell line (tumor of larynx) with inhibitory concentration percent of (IC %) range (32.43 % - 49.55%) and showed that the tested compounds had variable antimicrobial activities against selected bacteria and yeast when compared with selected standard drugs. Keywords: Quinolones, 8-hydroxyquinoline , N-heterocycles biological activity.

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Gudelis, Emilis, Sonata Krikštolaitytė, Monika Stančiauskaitė, Urtė Šachlevičiūtė, Aurimas Bieliauskas, Vaida Milišiūnaitė, Rokas Jankauskas, Neringa Kleizienė, Frank A. Sløk e Algirdas Šačkus. "Synthesis of New Azetidine and Oxetane Amino Acid Derivatives through Aza-Michael Addition of NH-Heterocycles with Methyl 2-(Azetidin- or Oxetan-3-Ylidene)Acetates". Molecules 28, n. 3 (21 gennaio 2023): 1091. http://dx.doi.org/10.3390/molecules28031091.

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Abstract (sommario):

In this paper, a simple and efficient synthetic route for the preparation of new heterocyclic amino acid derivatives containing azetidine and oxetane rings was described. The starting (N-Boc-azetidin-3-ylidene)acetate was obtained from (N-Boc)azetidin-3-one by the DBU-catalysed Horner–Wadsworth–Emmons reaction, followed by aza-Michael addition with NH-heterocycles to yield the target functionalised 3-substituted 3-(acetoxymethyl)azetidines. Methyl 2-(oxetan-3-ylidene)acetate was obtained in a similar manner, which was further treated with various (N-Boc-cycloaminyl)amines to yield the target 3-substituted 3-(acetoxymethyl)oxetane compounds. The synthesis and diversification of novel heterocyclic amino acid derivatives were achieved through the Suzuki–Miyaura cross-coupling from the corresponding brominated pyrazole–azetidine hybrid with boronic acids. The structures of the novel heterocyclic compounds were confirmed via 1H-, 13C-, 15N-, and 19F-NMR spectroscopy, as well as HRMS investigations.

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Bakibayev, A. A., K. B. Zhumanov, S. Yu Panshina, S. I. Gorbin, V. S. Malkov, I. G. Tsoy, B. K. Massalimova, G. K. Matniyazova e Е. А. Baybazarova. "Synthesis methods of phosphorylated carbamide containing acyclic and heterocyclic compounds". Bulletin of the Karaganda University. "Chemistry" series 95, n. 3 (30 settembre 2019): 115–57. http://dx.doi.org/10.31489/2019ch3/115-157.

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Articoli di riviste sul tema "Heterocyclic compounds"

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