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Journal articles on the topic 'DPP based molecules'

Author: Grafiati
Published: 6 September 2023

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1

Li, Dizao, Qiang Wang, Liping Wang, Weifeng Zhang, and Gui Yu. "Synthesis and Performance of (E)-3-Phenyl-2-(thiophen-2-yl)acrylonitrile-Based Small-Molecule Semiconductors." Organic Materials 01, no. 01 (November 2019): 078–87. http://dx.doi.org/10.1055/s-0039-3402057.

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Based on diketopyrrolopyrrole (DPP) and (E)-3-phenyl-2-(thiophen-2-yl)acrylonitrile (BVCNT)-linked conjugated backbones, three donor–acceptor type conjugated organic small-molecule compounds DPP-BVCNT, DPP-2FBVCNT, and DPP-3FBVCNT were designed and synthesized. Among them, the 2-decyltetradecyl side chain on the DPP acceptor unit was used to ensure the solubility of the material. The fluorine (F) atoms combined with the nitrile on the BVCNT donor unit were used to adjust electronic structures and charge carrier transport properties of the conjugated system. All the three small molecules exhibited good solution dispersibility and thermal stability, providing an important guarantee for the solution processing and annealing optimization of organic field-effect transistors (OFETs). The top-gate-bottom-contact OFET devices based on these compounds showed good ambipolar or p-type performances. The relationship between molecular structures and OFET performances indicated that the F-substitution and its position significantly affected their charge carrier transport properties. The F-substitution could remarkably change the performance from p-type to ambipolar especially for the outer-side-F-substituted compound DPP-2FBVCNT, which showed the best OFET performances with the maximum hole/electron mobilities of 0.023/0.220 cm2 V−1 s−1. These results provided a promising idea for developing small-molecule OFET materials with good solution processability, good thermal stability, and high ambipolar performances.
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2

Patil, Yuvraj, Rajneesh Misra, Abhishek Sharma, and Ganesh D. Sharma. "D–A–D–π–D–A–D type diketopyrrolopyrrole based small molecule electron donors for bulk heterojunction organic solar cells." Physical Chemistry Chemical Physics 18, no. 25 (2016): 16950–57. http://dx.doi.org/10.1039/c6cp02700h.

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3

Peng, Zhe, Shuangxiong Dai, Yingchun Ji, Bin Tong, Jianbing Shi, Zhengxu Cai, Junge Zhi, and Yuping Dong. "Ionic liquid crystals with aggregation-induced emission properties based on pyrrolo[3,2-b]pyrrole salt compounds." Materials Chemistry Frontiers 3, no. 7 (2019): 1385–90. http://dx.doi.org/10.1039/c9qm00208a.

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4

Liu, Hui, Xiao-Feng Zhang, Jing-Zhao Cheng, Ai-Guo Zhong, He-Rui Wen, and Shi-Yong Liu. "Novel Diketopyrrolopyrrole-Based π-Conjugated Molecules Synthesized Via One-Pot Direct Arylation Reaction." Molecules 24, no. 9 (May 7, 2019): 1760. http://dx.doi.org/10.3390/molecules24091760.

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Diketopyrrolopyrrole (DPP) is an important type of π-conjugated building block for high-performance organic electronic materials. DPP-based conjugated materials are usually synthesized via Suzuki, Stille, or Negishi cross-coupling reactions, which require organometallic precursors. In this paper, a series of novel phenyl-cored DPP molecules, including five meta-phenyl-cored molecules and four para-phenyl-cored molecules, have been synthesized in moderate to good yields, in a facile manner, through the Pd-catalyzed direct arylation of C–H bonds, and their optoelectrical properties have been investigated in detail. All new molecules have been fully characterized by NMR, MALDI-TOF MS, elemental analysis, UV–visible spectroscopy, and cyclic voltammetry. This synthetic strategy has evident advantages of atom- and step-economy and low cost, compared with traditional cross-coupling reactions.
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5

Kim, Yu Jin, Chang Eun Song, Sanjaykumar R. Suranagi, Jong-Cheol Lee, and Chan Eon Park. "Markedly different molecular formation in DPP-based small-molecule solar cells probed by grazing-incidence wide-angle X-ray scattering." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 73, no. 5 (September 19, 2017): 916–22. http://dx.doi.org/10.1107/s2052520617009933.

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This study comprehensively explores the nanostructural properties of two diketopyrrolo[3,4-c]pyrrole-1,4-dione (DPP)-based small molecules with different alkyl side groups and their blends with the fullerene derivative PC71BM, using grazing-incidence wide-angle X-ray scattering synchrotron techniques. Preferentially relative face-on orientation within the larger and more ordered stacking phase of SM1 with its shorter side group (ethylhexyl) was observed in the majority of both pristine and blend thin films, whereas SM2 crystals showed strictly perpendicular orientation. These contrasting crystalline characteristics led to significant differences in the results, from which crystalline structure–performance property correlations are proposed. Thus, the results not only demonstrate important scientific insights into the relationship between molecular structure and crystalline formation but also provide molecular design directions that will facilitate further improvement to the morphology and performance of DPP-based small-molecule solar cells.
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6

Kojima, Takahiko, Tatsuaki Nakanishi, Tatsuhiko Honda, and Shunichi Fukuzumi. "Photoinduced electron transfer in supramolecular assemblies involving saddle-distorted porphyrins and phthalocyanines." Journal of Porphyrins and Phthalocyanines 13, no. 01 (January 2009): 14–21. http://dx.doi.org/10.1142/s1088424609000164.

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Unique supramolecular assemblies are constructed based on a saddle-distorted non-planar porphyrin, dodecaphenylporphyrin ( H 2 DPP ), and its metal complexes. The saddle distortion facilitates protonation of pyrrole nitrogens to afford a stable diprotonated porphyrin, which can act as an electron acceptor. A diprotonated hydrochloride salt of a saddle-distorted dodecaphenylporphyrin ([ H 4 DPP ] Cl 2) forms a nano-sized channel structure called a "porphyrin nanochannel". Electron-donating molecules such as hydroquinones are included as guest molecules in the porphyrin nanochannel. Photoinduced electron transfer from the guest molecules to the singlet state of H 4 DPP 2+ occurs, producing H 4 DPP +• and cation radicals of the guest molecules. The saddle distortion also results in higher Lewis acidity at a metal center to maintain axial coordination of ligands, due to poor overlap of the lone-pair orbitals with the d orbitals of the metal center. By taking advantage of saddle distortion of both H 4 DPP 2+ and zinc phthalocyanine, 1,4,8,11,15,18,22,25-octaphenylphthalocyanine ( ZnOPPc ), a discrete supramolecular assembly composed of H 4 DPP 2+ and ZnOPPc , is obtained using 4-pyridinecarboxylate (4-PyCOO-) that connects the two components by hydrogen bonding and coordination bonding, respectively. Photoexcitation of the assembly results in efficient electron transfer from ZnOPPc to H 4 DPP 2+ in the supramolecular complex.
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7

Namepetra, Andrew, Elizabeth Kitching, Ala'a F. Eftaiha, Ian G. Hill, and Gregory C. Welch. "Understanding the morphology of solution processed fullerene-free small molecule bulk heterojunction blends." Physical Chemistry Chemical Physics 18, no. 18 (2016): 12476–85. http://dx.doi.org/10.1039/c6cp01269h.

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The impact of processing conditions on the morphological characteristics of bulk-heterojunction molecular blends prepared from small molecules based on diketopyrrolopyrrole (DPP) and perylene-diimide (PDI) chromophores have been investigated.
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8

Liu, Qian, Abhijith Surendran, Krishna Feron, Sergei Manzhos, Xuechen Jiao, Christopher R. McNeill, Steven E. Bottle, John Bell, Wei Lin Leong, and Prashant Sonar. "Diketopyrrolopyrrole based organic semiconductors with different numbers of thiophene units: symmetry tuning effect on electronic devices." New Journal of Chemistry 42, no. 6 (2018): 4017–28. http://dx.doi.org/10.1039/c7nj03505e.

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9

Zhao, Chaowei, Yiting Guo, Yuefeng Zhang, Nanfu Yan, Shengyong You, and Weiwei Li. "Diketopyrrolopyrrole-based conjugated materials for non-fullerene organic solar cells." Journal of Materials Chemistry A 7, no. 17 (2019): 10174–99. http://dx.doi.org/10.1039/c9ta01976f.

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10

Park, Keon Joo, Chae Won Kim, Min Jae Sung, Jiyoul Lee, and Young Tea Chun. "Semiconducting Polymer Nanowires with Highly Aligned Molecules for Polymer Field Effect Transistors." Electronics 11, no. 4 (February 18, 2022): 648. http://dx.doi.org/10.3390/electronics11040648.

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Conjugated polymers have emerged as promising materials for next-generation electronics. However, in spite of having several advantages, such as a low cost, large area processability and flexibility, polymer-based electronics have their own limitations concerning low electrical performance. To achieve high-performance polymer electronic devices, various strategies have been suggested, including aligning polymer backbones in the desired orientation. In the present paper, we report a simple patterning technique using a polydimethylsiloxane (PDMS) mold that can fabricate highly aligned nanowires of a diketopyrrolopyrrole (DPP)-based donor–acceptor-type copolymer (poly (diketopyrrolopyrrole-alt-thieno [3,2-b] thiophene), DPP-DTT) for high-performance field effect transistors. The morphology of the patterns was controlled by changing the concentration of the DPP-based copolymer solution (1, 3, 5 mg mL−1). The molecular alignment properties of three different patterns were observed with a polarized optical microscope, polarized UV-vis spectroscopy and an X-ray diffractometer. DPP-DTT nanowires made with 1 mg mL−1 solution are highly aligned and the polymer field-effect transistors based on nanowires exhibit more than a five times higher charge carrier mobility as compared to spin-coated film-based devices.
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11

Yang, Xue, Qing Yu, Nan Yang, Lei Xue, Jiawei Shao, Buhong Li, Jinjun Shao, and Xiaochen Dong. "Thieno[3,2-b]thiophene-DPP based near-infrared nanotheranostic agent for dual imaging-guided photothermal/photodynamic synergistic therapy." Journal of Materials Chemistry B 7, no. 15 (2019): 2454–62. http://dx.doi.org/10.1039/c8tb03185a.

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12

Song, Hao, Yao Gao, Weili Li, Hongkun Tian, Donghang Yan, Yanhou Geng, and Fosong Wang. "Synthesis and characterization of diketopyrrolopyrrole-based conjugated molecules flanked by indenothiophene and benzoindenothiophene derivatives." Journal of Materials Chemistry C 3, no. 42 (2015): 11135–43. http://dx.doi.org/10.1039/c5tc02288f.

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13

Kumar, C. H. Pavan, K. Ganesh, T. Suresh, Abhishek Sharma, K. Bhanuprakash, G. D. Sharma, and Malapaka Chandrasekharam. "Influence of thermal and solvent annealing on the morphology and photovoltaic performance of solution processed, D–A–D type small molecule-based bulk heterojunction solar cells." RSC Advances 5, no. 113 (2015): 93579–90. http://dx.doi.org/10.1039/c5ra16812k.

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Four new small molecules CSDPP9–CSDPP12 were obtained with appended electron donating units in the molecular terminals of a DPP core. On solvent and thermal annealing, for the CSDPP11:PC71BM blend, the BHJ device displayed a PCE of 5.47%.
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14

Hendsbee, Arthur D., Jon-Paul Sun, Lesley R. Rutledge, Ian G. Hill, and Gregory C. Welch. "Electron deficient diketopyrrolopyrrole dyes for organic electronics: synthesis by direct arylation, optoelectronic characterization, and charge carrier mobility." J. Mater. Chem. A 2, no. 12 (2014): 4198–207. http://dx.doi.org/10.1039/c3ta14414c.

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15

Hoang, Quoc Viet, Chang Eun Song, In-Nam Kang, Sang-Jin Moon, Sang Kyu Lee, Jong-Cheol Lee, and Won Suk Shin. "Low band gap diketopyrrolopyrrole-based small molecule bulk heterojunction solar cells: influence of terminal side chain on morphology and photovoltaic performance." RSC Advances 6, no. 34 (2016): 28658–65. http://dx.doi.org/10.1039/c6ra01103a.

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16

Tang, Ailing, Chuanlang Zhan, Jiannian Yao, and Erjun Zhou. "Design of Diketopyrrolopyrrole (DPP)-Based Small Molecules for Organic-Solar-Cell Applications." Advanced Materials 29, no. 2 (November 9, 2016): 1600013. http://dx.doi.org/10.1002/adma.201600013.

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17

Do, Thu Trang, Kira Rundel, Qinying Gu, Eliot Gann, Sergei Manzhos, Krishna Feron, John Bell, Christopher R. McNeill, and Prashant Sonar. "9-Fluorenone and 9,10-anthraquinone potential fused aromatic building blocks to synthesize electron acceptors for organic solar cells." New Journal of Chemistry 41, no. 8 (2017): 2899–909. http://dx.doi.org/10.1039/c6nj03938c.

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18

Chittepu, Veera C. S. R., Poonam Kalhotra, Tzayhri Osorio-Gallardo, Tzayhri Gallardo-Velázquez, and Guillermo Osorio-Revilla. "Repurposing of FDA-Approved NSAIDs for DPP-4 Inhibition as an Alternative for Diabetes Mellitus Treatment: Computational and in Vitro Study." Pharmaceutics 11, no. 5 (May 17, 2019): 238. http://dx.doi.org/10.3390/pharmaceutics11050238.

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A drug repurposing strategy could be a potential approach to overcoming the economic costs for diabetes mellitus (DM) treatment incurred by most countries. DM has emerged as a global epidemic, and an increase in the outbreak has led developing countries like Mexico, India, and China to recommend a prevention method as an alternative proposed by their respective healthcare sectors. Incretin-based therapy has been successful in treating diabetes mellitus, and inhibitors like sitagliptin, vildagliptin, saxagliptin, and alogliptin belong to this category. As of now, drug repurposing strategies have not been used to identify existing therapeutics that can become dipeptidyl peptidase-4 (DPP-4) inhibitors. Hence, this work presents the use of bioinformatics tools like the Activity Atlas model, flexible molecular docking simulations, and three-dimensional reference interaction site model (3D-RISM) calculations to assist in repurposing Food and Drug Administration (FDA)-approved drugs into specific nonsteroidal anti-inflammatory medications such as DPP-4 inhibitors. Initially, the Activity Atlas model was constructed based on the top scoring DPP-4 inhibitors, and then the model was used to understand features of nonsteroidal anti-inflammatory drugs (NSAIDs) as a function of electrostatic, hydrophobic, and active shape features of DPP-4 inhibition. The FlexX algorithm was used to infer protein–ligand interacting residues, and binding energy, to predict potential draggability towards the DPP-4 mechanism of action. 3D-RISM calculations on piroxicam-bound DPP-4 were used to understand the stability of water molecules at the active site. Finally, piroxicam was chosen as the repurposing drug to become a new DPP-4 inhibitor and validated experimentally using fluorescence spectroscopy assay. These findings are novel and provide new insights into the role of piroxicam as a new lead to inhibit DPP-4 and, taking into consideration the biological half-life of piroxicam, it can be proposed as a possible therapeutic strategy for treating diabetes mellitus.
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19

Patil, Yuvraj, Rajneesh Misra, F. C. Chen, M. L. Keshtov, and Ganesh D. Sharma. "Symmetrical and unsymmetrical triphenylamine based diketopyrrolopyrroles and their use as donors for solution processed bulk heterojunction organic solar cells." RSC Advances 6, no. 102 (2016): 99685–94. http://dx.doi.org/10.1039/c6ra10442h.

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Two small molecules DPP3 (D–π–A) and DPP4 (D–π–A–π–D) with triphenylamine (TPA) donors and diketopyrrolopyrrole (DPP) acceptors linked with ethyne linkers were designed and synthesized by the Pd-catalyzed Sonogashira cross-coupling reaction.
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20

Zhang, Jing, Chang He, Zhi-Guo Zhang, Dan Deng, Maojie Zhang, and Yongfang Li. "D-A-D structured organic molecules with diketopyrrolopyrrole acceptor unit for solution-processed organic solar cells." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2013 (April 13, 2014): 20130009. http://dx.doi.org/10.1098/rsta.2013.0009.

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Four solution-processable D-A-D structured organic molecules with diketopyrrolopyrrole (DPP) as acceptor unit and triphenylamine (TPA) or (4-hexyl)thieno [3,2-b]thiophene (HTT) as donor unit, DPP8-TPA, DPP8-TPA-OR, DPP6-HTT and DPP8-HTT, were designed and synthesized for the application as donor materials in solution-processed organic solar cells (OSCs). The molecules show broad absorption and relatively lower highest occupied molecular orbital energy levels. Photovoltaic properties of the molecules were investigated by fabricating the bulk-heterojunction OSCs with the molecules as donor and PC 71 BM as acceptor. Power conversion efficiency of the OSC based on DPP8-HTT reached 1.5% under the illumination of AM1.5, 100 mW cm −2 .
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21

Wang, Lingyun, Bihong Lai, Xueguang Ran, Hao Tang, and Derong Cao. "Recent Advances of Diketopyrrolopyrrole Derivatives in Cancer Therapy and Imaging Applications." Molecules 28, no. 10 (May 15, 2023): 4097. http://dx.doi.org/10.3390/molecules28104097.

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Cancer is threatening the survival of human beings all over the world. Phototherapy (including photothermal therapy (PTT) and photodynamic therapy (PDT)) and bioimaging are important tools for imaging–mediated cancer theranostics. Diketopyrrolopyrrole (DPP) dyes have received more attention due to their high thermal and photochemical stability, efficient reactive oxygen species (ROS) generation and thermal effects, easy functionalization, and tunable photophysical properties. In this review, we outline the latest achievements of DPP derivatives in cancer therapy and imaging over the past three years. DPP-based conjugated polymers and small molecules for detection, bioimaging, PTT, photoacoustic imaging (PAI)-guided PTT, and PDT/PTT combination therapy are summarized. Their design principles and chemical structures are highlighted. The outlook, challenges, and future opportunities for the development of DPP derivatives are also presented, which will give a future perspective for cancer treatment.
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22

Lim, Eunhee. "Effect of Alkyl Substituents on DPP ‐based Small Molecules for Organic Solar Cells." Bulletin of the Korean Chemical Society 41, no. 6 (June 2020): 639–43. http://dx.doi.org/10.1002/bkcs.12045.

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23

Roy, Shubham, Ratul Bhowmik, Sounok Sengupta, Sameer Sharma, Bharti Vyas, and Imran A Khan. "Pharmacoinformatics Profiling and Dynamic Studies of Selected Compounds Acting as Potential Inhibitors against DPP4 Enzyme." Oriental Journal Of Chemistry 37, no. 5 (October 30, 2021): 1017–29. http://dx.doi.org/10.13005/ojc/370502.

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DPP-IV rapidly degrades glucagon-like peptide-1 and glucose-dependent insulinotropic peptides. Delaying the breakdown of endogenous incretin hormones with DPP-IV inhibitors may help correct the physiologic deficit. The purpose of this work is to identify new compounds that inhibit the DPP-IV enzyme. The anticipated compounds were potent anti-diabetic candidates in this investigation. Two 2d QSAR models were created using 179 different substances from diverse sources. QSAR models were created using two methods. The first technique included docking score as an additional descriptor, while the second did not. Docking-based QSAR considered 74 compounds out of 179. Another approach used 40 molecules from 179 compounds. Each method had a precise strategy. Descriptors were computed using DRAGON for both training and test sets. Using DRAGON data, SYSTAT generated regression curves. The docking-based QSAR model produced R2=0.7098 (training set) and R2=0.9987 (test set), whereas the other technique produced R2=0.7644 (training set) and R2=0.9857 (test set).
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24

Cortizo-Lacalle, Diego, Calvyn T. Howells, Upendra K. Pandey, Joseph Cameron, Neil J. Findlay, Anto Regis Inigo, Tell Tuttle, Peter J. Skabara, and Ifor D. W. Samuel. "Solution processable diketopyrrolopyrrole (DPP) cored small molecules with BODIPY end groups as novel donors for organic solar cells." Beilstein Journal of Organic Chemistry 10 (November 18, 2014): 2683–95. http://dx.doi.org/10.3762/bjoc.10.283.

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Two novel triads based on a diketopyrrolopyrrole (DPP) central core and two 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) units attached by thiophene rings have been synthesised having high molar extinction coefficients. These triads were characterised and used as donor materials in small molecule, solution processable organic solar cells. Both triads were blended with PC71BM as an acceptor in different ratios by wt % and their photovoltaic properties were studied. For both the triads a modest photovoltaic performance was observed, having an efficiency of 0.65%. Moreover, in order to understand the ground and excited state properties and vertical absorption profile of DPP and BODIPY units within the triads, theoretical DFT and TDDFT calculations were performed.
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25

Yu, Delong, Yu Liu, Manjun Xiao, Qunping Fan, Wenyan Su, Xiao Li, Hua Tan, Yafei Wang, Renqiang Yang, and Weiguo Zhu. "Synthesis and photovoltaic performance of DPP-based small molecules with tunable energy levels by altering the molecular terminals." Dyes and Pigments 125 (February 2016): 151–58. http://dx.doi.org/10.1016/j.dyepig.2015.10.006.

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26

Khalsa, O., J. W. Yoon, S. Torres-Schumann, and K. A. Wharton. "TGF-beta/BMP superfamily members, Gbb-60A and Dpp, cooperate to provide pattern information and establish cell identity in the Drosophila wing." Development 125, no. 14 (July 15, 1998): 2723–34. http://dx.doi.org/10.1242/dev.125.14.2723.

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Within a developing organism, cells receive many signals which control their proliferation, fate specification and differentiation. One group of such proteins is the TGF-beta/BMP class of related signaling molecules. Based on expression studies, multiple members of this class of ligands must impinge upon the same cells of a developing tissue; however, the role that multiple TGF-beta/BMP ligands may play in directing the development of such a tissue is not understood. Here we provide evidence that multiple BMPs are required for growth and patterning of the Drosophila wing. The Drosophila BMP gene, gbb-60A, exhibits a requirement in wing morphogenesis distinct from that shown previously for dpp, a well-characterized Drosophila BMP member. gbb-60A mutants exhibit a loss of pattern elements from the wing, particularly those derived from cells in the posterior compartment, consistent with the gbb-60A RNA and protein expression pattern. Based on genetic analysis and expression studies, we conclude that Gbb-60A must signal primarily as a homodimer to provide patterning information in the wing imaginal disc. We demonstrate that gbb-60A and dpp genetically interact and that specific aspects of this interaction are synergistic while others are antagonistic. We propose that the positional information received by a cell at a particular location within the wing imaginal disc depends on the balance of Dpp to Gbb-60A signaling. Furthermore, the critical ratio of Gbb-60A to Dpp signaling appears to be mediated by both Tkv and Sax type I receptors.
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27

Eom, Yoonho, Chang Eun Song, Won Suk Shin, Sang Kyu Lee, and Eunhee Lim. "Rational design of π-bridges for ambipolar DPP-RH-based small molecules in organic photovoltaic cells." Journal of Industrial and Engineering Chemistry 45 (January 2017): 338–48. http://dx.doi.org/10.1016/j.jiec.2016.10.001.

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28

Комолов, А. С., Э. Ф. Лазнева, Н. Б. Герасимова, А. В. Барамыгин, В. С. Соболев, С. А. Пшеничнюк, Н. Л. Асфандиаров, В. А. Крайкин, and B. Handke. "Плотность свободных электронных состояний полупроводниковых пленок молекул нафталина и дифенилфталида, модифицированных электроактивными функциональными группами." Физика твердого тела 62, no. 7 (2020): 1116. http://dx.doi.org/10.21883/ftt.2020.07.49483.006.

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The results on comparing the peak structure of the density of unoccupied electronic states (DOUS) of ultrathin films of naphthalene anhydride-1,4,5,8-teracabonic acid (NTCDA) and naphthalene-1,8-dicarboxylic acid anhydride (NDCA) and of two types of phthalide-based films: 3,3-bis (phenyl) phthalide (DPP) and 3,3-bis (phenyl) phthalide-4 ′, 4′-dicarboxylic acid (DPP-DCA) are presented. The measurements of the structure of the unoccupied electronic states in the energy range from 5 eV to 20 eV above the Fermi level of the films studied having thickness of 8–10 nm were conducted using the total current spectroscopy (TCS) technique. Analysis of the experimental results was conducted using the model total current spectra and DOUS dependences generated using the calculated orbital energies of the studied molecules by means of the density functional theory (DFT) method at the B3LYP/6-31G(d) level. The difference in the DOUS spectra of NTCDA and NDCA films is characterized by the shift of the main DOUS maxima of the NTCDA film to lower energies by about 1 eV at energies less than 12.5 eV, and at higher energies the DOUS maxima are shifted by 1.5-2 eV. The energy positions of the maxima of the total current spectra of the DPP-DCA and DPP films practically do not change when using various substrates: highly ordered pyrolytic graphite (HOPG) and layer-by-layer deposited CdS. The relative intensities of the maxima differ when using different substrates. The characteristic shift of the maxima of the total current spectra of DPP-DCA films is about 1 eV at energies less than 12.5 eV above the Fermi level and 1.5-2 eV and at higher energies, compared with the position of the corresponding maxima of the DPP films.
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29

Bernardini, Federico, Annunziata Nusca, Federica Coletti, Ylenia La Porta, Mariagrazia Piscione, Francesca Vespasiano, Fabio Mangiacapra, et al. "Incretins-Based Therapies and Their Cardiovascular Effects: New Game-Changers for the Management of Patients with Diabetes and Cardiovascular Disease." Pharmaceutics 15, no. 7 (July 1, 2023): 1858. http://dx.doi.org/10.3390/pharmaceutics15071858.

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Atherosclerosis is the leading cause of death worldwide, especially in patients with type 2 diabetes mellitus (T2D). GLP-1 receptor agonists and DPP-4 inhibitors were demonstrated to play a markedly protective role for the cardiovascular system beyond their glycemic control. Several cardiovascular outcome trials (CVOT) reported the association between using these agents and a significant reduction in cardiovascular events in patients with T2D and a high cardiovascular risk profile. Moreover, recent evidence highlights a favorable benefit/risk profile in myocardial infarction and percutaneous coronary revascularization settings. These clinical effects result from their actions on multiple molecular mechanisms involving the immune system, platelets, and endothelial and vascular smooth muscle cells. This comprehensive review specifically concentrates on these cellular and molecular processes mediating the cardiovascular effects of incretins-like molecules, aiming to improve clinicians’ knowledge and stimulate a more extensive use of these drugs in clinical practice as helpful cardiovascular preventive strategies.
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30

Xue, Xiaohong, Yaoming Su, Hailei Su, Dongping Fan, Hongliang Jia, Xiaoting Chu, Xiaoyang Song, et al. "Occurrence of Phthalates in Bottled Drinks in the Chinese Market and Its Implications for Dietary Exposure." Molecules 26, no. 19 (October 6, 2021): 6054. http://dx.doi.org/10.3390/molecules26196054.

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Ubiquitous occurrences of phthalic acid esters (PAEs) or phthalates in a variety of consumer products have been demonstrated. Nevertheless, studies on their occurrence in various types of bottled drinks are limited. In this study, fifteen PAEs were analyzed in six categories of bottled drinks (n = 105) collected from the Chinese market, including mineral water, tea drinks, energy drinks, juice drinks, soft drinks, and beer. Among the 15 PAEs measured, DEHP was the most abundant phthalate with concentrations ranging from below the limit of quantification (LOQ) to 41,000 ng/L at a detection rate (DR) of 96%, followed by DIBP (DR: 88%) and DBP (DR: 84%) with respective concentration ranges of below LOQ to 16,000 and to 4900 ng/L. At least one PAE was detected in each drink sample, and the sum concentrations of 15 PAEs ranged from 770 to 48,004 ng/L (median: 6286 ng/L). Significant differences with respect to both PAE concentrations and composition profiles were observed between different types of bottled drinks. The median sum concentration of 15 PAEs in soft drinks was over five times higher than that detected in mineral water; different from other drink types. Besides DEHP, DBIP, and DBP, a high concentration of BMEP was also detected in a tea drink. The estimated daily dietary intake of phthalates (EDIdrink) through the consumption of bottled drinks was calculated based on the concentrations measured and the daily ingestion rates of bottled drink items. The EDIdrink values for DMP, DEP, DIBP, DBP, BMEP, DAP, BEEP, BBP, DCP, DHP, BMPP, BBEP, DEHP, DOP, and DNP through the consumption of bottled mineral water (based on mean concentrations) were 0.45, 0.33, 12.5, 3.67, 2.10, 0.06, 0.32, 0.16, 0.10, 0.09, 0.05, 0.81, 112, 0.13, and 0.20 ng/kg-bw/d, respectively, for Chinese adults. Overall, the EDIdrink values calculated for phthalates through the consumption of bottled drinks were below the oral reference doses suggested by the United States Environmental Protection Agency (U.S. EPA).
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Huang, Zhuo-Ting, Cong-Cheng Fan, Guo-Biao Xue, Jia-Ke Wu, Shuang Liu, Huan-Bin Li, Hong-Zheng Chen, and Han-Ying Li. "Solution-grown aligned crystals of diketopyrrolopyrroles (DPP)-based small molecules: Rough surfaces and relatively low charge mobility." Chinese Chemical Letters 27, no. 4 (April 2016): 523–26. http://dx.doi.org/10.1016/j.cclet.2016.01.054.

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32

Jin, Ruifa, Xiaofei Zhang, and Wenmin Xiao. "Theoretical Studies of Photophysical Properties of D−π−A−π−D-Type Diketopyrrolopyrrole-Based Molecules for Organic Light-Emitting Diodes and Organic Solar Cells." Molecules 25, no. 3 (February 4, 2020): 667. http://dx.doi.org/10.3390/molecules25030667.

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A series of D–π–A diketopyrrolopyrrole(DPP)-based small molecules were designed for organic light-emitting diode(OLEDs) and organic solar cell(OSCs) applications. Applying the PBE0/6-31G(d,p) method, the ground state geometry and relevant electronic properties were investigated. The first excited singlet state geometry and the absorption and fluorescent spectra were simulated at the TD-PBE0/6-31G(d,p) level. The calculated results revealed that the photophysical properties were affected through the introduction of different end groups. Furthermore, the electronic transitions corresponding to absorption and emission exhibited an intramolecular charge transfer feature. Our results suggest that the designed molecules acted not only as luminescent for OLEDs, but also as donor materials in OSCs. Moreover, they can also be used as potential electron transfer materials for OLEDs and OSCs.
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Meng, Qing-Guo, Lin-Tong Wang, Ji-Tao Lu, Xin Wang, Wei Lu, and Zi-Yu Song. "Structures and Photoluminescence Properties of Four Cadmium(II) Coordination Polymers Synthesized by Rigid Ligands and N-Donor Ligands." Australian Journal of Chemistry 68, no. 5 (2015): 742. http://dx.doi.org/10.1071/ch14341.

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Four metal–organic coordination polymers, [Cd2(dna)2(2,2′-bpy)2]n (1), {[Cd4(dna)4(im)3]·5H2O}n (2), {[Cd2(dna)2(4,4′-bpy)(H2O)2]·2EtOH}n (3), and {[Cd4(dna)4(1,3-dpp)4(H2O)4]·2H2O}n (4) (H2dna = 4,6-dimethyl-5-nitroisophthalic acid; 2,2′-bpy = 2,2′-bipyridine; im = imidazole; 4,4′-bpy = 4,4′-bipyridine; 1,3-dpp = 1,3-di(4-pyridyl)propane; and EtOH = ethanol, have been solvothermally synthesized and characterized. Compound 1 displays a one-dimensional (1D) ladder structure and the neighbouring ladders are further stabilized by π···π interactions to form a two-dimensional (2D) layer. Compound 2 forms a 2D layer based on infinite 1D [Cd2(COO)4]n chain and the im ligands act as terminal ligands, preventing expansion of the dimensionality. Compound 3 features a 2D 44-sql layer based on binuclear [Cd2(COO)4] secondary building units as 4-connected nodes, and is further linked to be an unusual three-dimensional (3D) supramolecular architecture by hydrogen bonds involving the coordinated water molecules, carboxylate groups, and lattice ethanol molecules. Compound 4 possesses a 2-fold interpenetrated dia net. The diverse structures and topologies of compounds 1–4 indicate that the N-containing ligands have significant effects on the formation of the final network structures. In addition, the thermal stabilities, structure comparison, and photoluminescence properties of the complexes have been investigated.
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34

Turecka, Katarzyna, Agnieszka Chylewska, Aleksandra M. Dąbrowska, Rafał Hałasa, Czesława Orlewska, and Krzysztof Waleron. "Ru(II) Oxygen Sensors for Co(III) Complexes and Amphotericin B Antifungal Activity Detection by Phosphorescence Optical Respirometry." International Journal of Molecular Sciences 24, no. 10 (May 14, 2023): 8744. http://dx.doi.org/10.3390/ijms24108744.

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The measurement of oxygen consumption is an important element in the understanding of an organism’s metabolic state. Oxygen is also a phosphorescence quencher, which allows the evaluation of phosphorescence emitted by oxygen sensors. Two Ru(II)-based oxygen-sensitive sensors were used to study the effect of chemical compounds [(1) = [CoCl2(dap)2]Cl, and (2) = [CoCl2(en)2]Cl (AmB = amphotericin B) against reference and clinical strains of Candida albicans. The tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] chloride ([Ru(DPP)3]Cl2) (Box) adsorbed onto the DavisilTM silica gel was embedded in the silicone rubber Lactite NuvaSil® 5091 and the coating on the bottom of 96-well plates. The water-soluble oxygen sensor (BsOx = tris-[(4,7-diphenyl-1,10-phenanthrolinedisulphonic acid disodium)ruthenium(II)] chloride ‘x’ hydrate = {Ru[DPP(SO3Na)2]3}Cl2 = water molecules were omitted in the BsOx formula) was synthesized and characterized by RP-UHPLC, LCMS, MALDI, elemental analysis, ATR, UV-Vis, 1H NMR, and TG/IR techniques. The microbiological studies were performed in the environment of RPMI broth and blood serum. Both Ru(II)-based sensors turned out to be useful in the study of the activity of Co(III) complexes and the commercial antifungal drug amphotericin B. In addition, a new activity of the oxygen sensor, the soluble Ru(II) complex BsOx, was demonstrated, which is a mixture with amphotericin B that caused a significant increase in its antifungal activity. Thus, it is also possible to demonstrate the synergistic effect of compounds active against the microorganisms under study.
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35

Kim, Y., C. E. Song, E. J. Ko, D. Kim, S. J. Moon, and E. Lim. "DPP-based small molecule, non-fullerene acceptors for “channel II” charge generation in OPVs and their improved performance in ternary cells." RSC Advances 5, no. 7 (2015): 4811–21. http://dx.doi.org/10.1039/c4ra12184h.

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Three diketopyrrolopyrrole-thiophene-based small molecules were synthesized substituting electron-withdrawing cyanide group in different positions and introduced as acceptors in organic photovoltaic cells.
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36

Kovalenko, Alexander, Darina Stoyanova, Jan Pospisil, Ivaylo Zhivkov, Ladislav Fekete, Daniela Karashanova, Irena Kratochvílová, Martin Vala, and Martin Weiter. "Morphology versus Vertical Phase Segregation in Solvent Annealed Small Molecule Bulk Heterojunction Organic Solar Cells." International Journal of Photoenergy 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/238981.

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The deep study of solvent annealed small molecules bulk heterojunction organic solar cells based on DPP(TBFu)2 : PC60BM blend is carried out. To reveal the reason of the solvent annealing advantage over the thermal one, capacitance-voltage measurements were applied. It was found that controlling the vertical phase segregation in the solar cells a high fullerene population in the vicinity of the cathode could be achieved. This results in increase of the shunt resistance of the cell, thus improving the light harvesting efficiency.
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37

Gevaerts, Veronique S., Eva M. Herzig, Mindaugas Kirkus, Koen H. Hendriks, Martijn M. Wienk, Jan Perlich, Peter Müller-Buschbaum, and René A. J. Janssen. "Influence of the Position of the Side Chain on Crystallization and Solar Cell Performance of DPP-Based Small Molecules." Chemistry of Materials 26, no. 2 (December 20, 2013): 916–26. http://dx.doi.org/10.1021/cm4034484.

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38

Greco, Salvatore, Vincenzo M. Monda, Giorgia Valpiani, Nicola Napoli, Carlo Crespini, Fabio Pieraccini, Anna Marra, and Angelina Passaro. "The Impact of GLP-1 RAs and DPP-4is on Hospitalisation and Mortality in the COVID-19 Era: A Two-Year Observational Study." Biomedicines 11, no. 8 (August 18, 2023): 2292. http://dx.doi.org/10.3390/biomedicines11082292.

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Novel antidiabetic drugs have the ability to produce anti-inflammatory effects regardless of their glucose-lowering action. For this reason, these molecules (including GLP-1 RAs and DPP-4is) were hypothesized to be effective against COVID-19, which is characterized by cytokines hyperactivity and multiorgan inflammation. The aim of our work is to explore the potential protective role of GLP-1 RAs and DPP-4is in COVID-19 (with the disease intended to be a model of an acute stressor) and non-COVID-19 patients over a two-year observation period. Retrospective and one-versus-one analyses were conducted to assess the impact of antidiabetic drugs on the need for hospitalization (in both COVID-19- and non-COVID-19-related cases), in-hospital mortality, and two-year mortality. Logistic regression analyses were conducted to identify the variables associated with these outcomes. Additionally, log-rank tests were used to plot survival curves for each group of subjects, based on their antidiabetic treatment. The performed analyses revealed that despite similar hospitalization rates, subjects undergoing home therapy with GLP-1 RAs exhibited significantly lower mortality rates, even over a two-year period. These individuals demonstrated improved survival estimates both within hospital and non-hospital settings, even during a longer observation period.
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39

Chu, Cheng Shane. "Optical Fiber Oxygen Sensor Based on Ru (II) Complex and Porous Silica Nanoparticles Embedded in Sol-Gel Matrix." Key Engineering Materials 516 (June 2012): 612–17. http://dx.doi.org/10.4028/www.scientific.net/kem.516.612.

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This paper presents a high-sensitivity oxygen sensor that comprises an optical fibre coated at one end with tris (4, 7-diphenyl-1, 10-phenanthroline) ruthenium (II) ([Ru (dpp)3]2+) and porous silica nanoparticles embedded in an n-octyltriethoxysilane (Octyl-triEOS)/tetraethylorthosilane (TEOS) composite xerogel. The sensitivity of the optical oxygen sensor is quantified in terms of the ratio IN2/IO2, where IN2 and IO2 represent the detected fluorescence intensities in pure nitrogen and pure oxygen environments, respectively. The experimental results show that the oxygen sensor has a sensitivity of 26. The experimental results show that compared to oxygen sensor based on Ru (II) complex immobilized in the sol-gel matrix, the proposed optical fibre oxygen sensor has higher sensitivity. In addition to the increased surface area per unit mass of the sensing surface, the porous silica nanoparticles increase the sensitivity because a substantial number of aerial oxygen molecules penetrate the porous silica shell. The proposed optical sensor has the advantages of easy fabrication, low cost, fast response and high sensitivity for oxygen monitoring using a cheap LED as a light source.
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40

Kim, Ji-Hoon, Jong Baek Park, Hoichang Yang, In Hwan Jung, Sung Cheol Yoon, Dongwook Kim, and Do-Hoon Hwang. "Controlling the Morphology of BDTT-DPP-Based Small Molecules via End-Group Functionalization for Highly Efficient Single and Tandem Organic Photovoltaic Cells." ACS Applied Materials & Interfaces 7, no. 43 (October 26, 2015): 23866–75. http://dx.doi.org/10.1021/acsami.5b05248.

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41

Vegiraju, Sureshraju, Cheng-Ming Hsieh, Deng-Yi Huang, Yen-Chia Chen, Pragya Priyanka, Jen-Shyang Ni, Firdausy Amalina Esya, et al. "Synthesis and characterization of solution-processable diketopyrrolopyrrole (DPP) and tetrathienothiophene (TTA)-based small molecules for organic thin film transistors and organic photovoltaic cells." Dyes and Pigments 133 (October 2016): 280–91. http://dx.doi.org/10.1016/j.dyepig.2016.05.041.

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42

Song, Chang Eun, Yu Jin Kim, Sanjaykumar R. Suranagi, Gururaj P. Kini, Sangheon Park, Sang Kyu Lee, Won Suk Shin, et al. "Impact of the Crystalline Packing Structures on Charge Transport and Recombination via Alkyl Chain Tunability of DPP-Based Small Molecules in Bulk Heterojunction Solar Cells." ACS Applied Materials & Interfaces 8, no. 20 (May 13, 2016): 12940–50. http://dx.doi.org/10.1021/acsami.6b01576.

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43

Borges, Nuno, Luís G. Gonçalves, Marta V. Rodrigues, Filipa Siopa, Rita Ventura, Christopher Maycock, Pedro Lamosa, and Helena Santos. "Biosynthetic Pathways of Inositol and Glycerol Phosphodiesters Used by the Hyperthermophile Archaeoglobus fulgidus in Stress Adaptation." Journal of Bacteriology 188, no. 23 (October 6, 2006): 8128–35. http://dx.doi.org/10.1128/jb.01129-06.

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ABSTRACT Archaeoglobus fulgidus accumulates di-myo-inositol phosphate (DIP) and diglycerol phosphate (DGP) in response to heat and osmotic stresses, respectively, and the level of glycero-phospho-myo-inositol (GPI) increases primarily when the two stresses are combined. In this work, the pathways for the biosynthesis of these three compatible solutes were established based on the detection of the relevant enzymatic activities and characterization of the intermediate metabolites by nuclear magnetic resonance analysis. The synthesis of DIP proceeds from glucose-6-phosphate via four steps: (i) glucose-6-phosphate was converted into l-myo-inositol 1-phosphate by l-myo-inositol 1-phosphate synthase; (ii) l-myo-inositol 1-phosphate was activated to CDP-inositol at the expense of CTP; this is the first demonstration of CDP-inositol synthesis in a biological system; (iii) CDP-inositol was coupled with l-myo-inositol 1-phosphate to yield a phosphorylated intermediate, 1,1′-di-myo-inosityl phosphate 3-phosphate (DIPP); (iv) finally, DIPP was dephosphorylated into DIP by the action of a phosphatase. The synthesis of the two other polyol-phosphodiesters, DGP and GPI, proceeds via the condensation of CDP-glycerol with the respective phosphorylated polyol, glycerol 3-phosphate for DGP and l-myo-inositol 1-phosphate for GPI, yielding the respective phosphorylated intermediates, 1X,1′X-diglyceryl phosphate 3-phosphate (DGPP) and 1-(1X-glyceryl) myo-inosityl phosphate 3-phosphate (GPIP), which are subsequently dephosphorylated to form the final products. The results disclosed here represent an important step toward the elucidation of the regulatory mechanisms underlying the differential accumulation of these compounds in response to heat and osmotic stresses.
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44

Sivakumar, Ponnurengam Malliappan, Veluchamy Prabhawathi, Ali Zarrabi, Sohail Akthar, and Pranav Kumar Prabhakar. "Current Trends in the Therapeutic Strategies for Diabetes Management." Current Medicinal Chemistry 28, no. 23 (August 2, 2021): 4616–37. http://dx.doi.org/10.2174/0929867328666210218183914.

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Diabetes mellitus is one of the fastest-growing non-communicable diseases. Diabetes mellitus is caused due by the destruction of pancreatic β-cell or due to insulin resistance and characterized by hyperglycemia. Diabetes imposes a very serious economic crisis as the diabetic drug market is growing very rapidly. Even after very path-breaking scientific discoveries, the availability of better healthcare infrastructure, and a rise in literacy rates, the diabetes burden is continuously spreading in various sections all over the world but more especially in low- and middle-income countries. The recent developments in scientific discoveries have given several new generations of antidiabetic medicines such as sulphonylurea, biguanides, thiazolidinedione, α-glucosidase inhibitors. All these drugs have proved a significant reduction in blood glucose level. There are some new classes of hypoglycaemic drugs that have also been developed and reported, such as GLP-1 analogous, DPP-IV inhibitors, amylin inhibitors, and peroxisome proliferator- activated receptors. There are some active molecules and bioactive substances that have been purified from herbs and plants, which add value to the war against diabetes. These phytoconstituents have overturned drug development and lead identification for drugs against diabetes. The review also focuses on some critical areas of diabetes with more focus on statin-based diabetes management approach and stem cell therapy based next generation antidiabetic therapy.
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45

Lukoyanov, Anton N., Iakov S. Fomenko, Marko I. Gongola, Lidia S. Shul’pina, Nikolay S. Ikonnikov, Georgiy B. Shul’pin, Sergey Y. Ketkov, et al. "Novel Oxidovanadium Complexes with Redox-Active R-Mian and R-Bian Ligands: Synthesis, Structure, Redox and Catalytic Properties." Molecules 26, no. 18 (September 21, 2021): 5706. http://dx.doi.org/10.3390/molecules26185706.

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A new monoiminoacenaphthenone 3,5-(CF3)2C6H3-mian (complex 2) was synthesized and further exploited, along with the already known monoiminoacenaphthenone dpp-mian, to obtain oxidovanadium(IV) complexes [VOCl2(dpp-mian)(CH3CN)] (3) and [VOCl(3,5-(CF3)2C6H3-bian)(H2O)][VOCl3(3,5-(CF3)2C6H3-bian)]·2.85DME (4) from [VOCl2(CH3CN)2(H2O)] (1) or [VCl3(THF)3]. The structure of all compounds was determined using X-ray structural analysis. The vanadium atom in these structures has an octahedral coordination environment. Complex 4 has an unexpected structure. Firstly, it contains 3,5-(CF3)2C6H3-bian instead of 3,5-(CF3)2C6H3-mian. Secondly, it has a binuclear structure, in contrast to 3, in which two oxovanadium parts are linked to each other through V=O···V interaction. This interaction is non-covalent in origin, according to DFT calculations. In structures 2 and 3, non-covalent π-π staking interactions between acenaphthene moieties of the neighboring molecules (distances are 3.36–3.40 Å) with an estimated energy of 3 kcal/mol were also found. The redox properties of the obtained compounds were studied using cyclic voltammetry in solution. In all cases, the reduction processes initiated by the redox-active nature of the mian or bian ligand were identified. The paramagnetic nature of complexes 3 and 4 has been proven by EPR spectroscopy. Complexes 3 and 4 exhibited high catalytic activity in the oxidation of alkanes and alcohols with peroxides. The yields of products of cyclohexane oxidation were 43% (complex 3) and 27% (complex 4). Based on the data regarding the study of regio- and bond-selectivity, it was concluded that hydroxyl radicals play the most crucial role in the reaction. The initial products in the reactions with alkanes are alkyl hydroperoxides, which are easily reduced to their corresponding alcohols by the action of triphenylphosphine (PPh3). According to the DFT calculations, the difference in the catalytic activity of 3 and 4 is most likely associated with a different mechanism for the generation of ●OH radicals. For complex 4 with electron-withdrawing CF3 substituents at the diimine ligand, an alternative mechanism, different from Fenton’s and involving a redox-active ligand, is assumed.
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46

Tzachanis, Dimitrios, Esther M. Lafuente, Lequn Li, Alla Berezovskaya, Gordon J. Freeman, and Vassiliki A. Boussiotis. "Twisted Gastrulation (Tsg), an Evolutionarily Conserved, Secreted, Morphogenetic Protein Enhances TGF-b Signaling in T Lymphocytes." Blood 106, no. 11 (November 16, 2005): 341. http://dx.doi.org/10.1182/blood.v106.11.341.341.

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Abstract We have previously determined that quiescent T cells express Tob, a member of the novel APRO gene family, which functions to repress T cell activation. Tob is as a transcriptional regulator and may regulate mRNA transcription. To identify genes that are regulated by Tob, Jurkat T cells were transfected with Tob cDNA or empty vector. Differential gene expression was determined by suppression subtractive hybridization. Twisted Gastrulation (Tsg) was one of the genes suppressed by Tob. Tsg is an evolutionarily conserved secreted protein that interacts with Drosophila Decapentaplegic (Dpp) and its vertebrate orthologs BMP2/4, and also the extracellular Dpp/BMP inhibitors short gastrulation (sog) and chordin. As a result, Tsg affects the binding of Dpp/BMP2/4 to their receptors and subsequent downstream signaling. BMPs belong to a family of secreted signaling molecules the founder of which, TGF-b, is essential for immune homeostasis and maintenance of T cell quiescence. In the thymus, Tsg functions as a regulator of thymocyte development by inhibiting BMP2/4 signaling which arrests thymocyte differentiation. Here, we examined Tsg expression and function in mature CD4+ human T cells. Tsg mRNA was expressed at very low levels in unstimulated T cells and was highly upregulated after activation by TCR/CD3 and either CD28, IL-2 or PMA. To determine the function of Tsg, we generated recombinant human Tsg tagged with V5 epitope. Based on its effects on thymocytes, we hypothesized that Tsg may regulate BMP2/4-mediated effects on mature T cells. Culture of CD4+ T cells with various concentrations of BMP2 or BMP4 in the presence or absence of anti-CD3 mAb did not affect T cell proliferation or cytokine production. Addition of Tsg to cultures containing BMP2/4 did not alter T cell responses. Because our results showed that Tsg mRNA was induced after activation, we tested pre-activated, polyclonal CD4+ alloreactive T cell lines. Neither BMP2 nor BMP4 had any effect on proliferation of alloreactive T cell lines in the presence or absence of anti-CD3 mAb. Strikingly, Tsg induced a significant inhibitory effect on CD3-mediated proliferation and cytokine production, including IL-2, IL-4, IFN-g and IL-10. This effect was not altered by the presence of BMP2 or BMP4. In contrast, Tsg enhanced the inhibitory effect of TGF-b1 suggesting that Tsg regulates TGF-b and not BMP downstream signaling in pre-activated, mature CD4+ T cells. Consistent with this hypothesis, Tsg did not affect phosphorylation of the BMP-specific Smad1, but induced phosphorylation of the TGF-b-specific Smad2 and mediated DNA binding on Smad3/4 consensus sites. In vitro association assays using recombinant Tsg-V5 and TGF-b revealed a direct interaction of these proteins as determined by co-immunoprecipitation followed by western blot with V5-specific and TGF-b-specific antibodies. Moreover, soluble anti-TGF-b receptor reversed the inhibitory effect of Tsg on pre-activated T cells either in the presence or in the absence of TGF-b, providing functional evidence for the biological significance of the Tsg/TGF-b interaction. Our results show that Tsg is a potent agonist of TGF-b downstream signaling in human CD4+ T cells and suggest that enhancement of TGF-b mediating signaling by Tsg may represent a novel target for molecular intervention for induction of transplantation tolerance.
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47

Narayanaswamy, K., A. Venkateswararao, Vinay Gupta, Suresh Chand, and Surya Prakash Singh. "NIR absorbing D–π–A–π–D structured diketopyrrolopyrrole–dithiafulvalene based small molecule for solution processed organic solar cells." Chemical Communications 52, no. 1 (2016): 210–13. http://dx.doi.org/10.1039/c5cc07435e.

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A new low band gap small molecule DPP–DTF with a D–π–A–π–D molecular structure composed of a dithiafulvalene (DTF) donor and a diketopyrrolopyrrole (DPP) acceptor was synthesized and tested for organic solar cells.
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48

Billet, Kévin, Magdalena Anna Malinowska, Thibaut Munsch, Marianne Unlubayir, Sophie Adler, Guillaume Delanoue, and Arnaud Lanoue. "Semi-Targeted Metabolomics to Validate Biomarkers of Grape Downy Mildew Infection Under Field Conditions." Plants 9, no. 8 (August 10, 2020): 1008. http://dx.doi.org/10.3390/plants9081008.

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Grape downy mildew is a devastating disease worldwide and new molecular phenotyping tools are required to detect metabolic changes associated to plant disease symptoms. In this purpose, we used UPLC-DAD-MS-based semi-targeted metabolomics to screen downy mildew symptomatic leaves that expressed oil spots (6 dpi, days post-infection) and necrotic lesions (15 dpi) under natural infections in the field. Leaf extract analyses enabled the identification of 47 metabolites belonging to the primary metabolism including 6 amino acids and 1 organic acid, as well as an important diversity of specialized metabolites including 9 flavonols, 11 flavan-3-ols, 3 phenolic acids, and stilbenoids with various degree of polymerization (DP) including 4 stilbenoids DP1, 8 stilbenoids DP2, and 4 stilbenoids DP3. Principal component analysis (PCA) was applied as unsupervised multivariate statistical analysis method to reveal metabolic variables that were affected by the infection status. Univariate and multivariate statistics revealed 33 and 27 metabolites as relevant infection biomarkers at 6 and 15 dpi, respectively. Correlation-based networks highlighted a general decrease of flavonoid-related metabolites, whereas stilbenoid DP1 and DP2 concentrations increased upon downy mildew infection. Stilbenoids DP3 were identified only in necrotic lesions representing late biomarkers of downy mildew infection.
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49

Ha, Jung-Hye, Eun-Hee Kim, Hae-Kap Cheong, and Kyoung-Seok Ryu. "Crystal structures of LsrR complexed with p-AI-2 reveal distinct mechanisms." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C580. http://dx.doi.org/10.1107/s2053273314094194.

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Quorum sensing (QS) is a cell-to-cell communication system and responsible for a variety of bacterial phenotypes including virulence and biofilm formation. QS is mediated by small molecules, autoinducers (AIs), including AI-2 that is secreted by both Gram (+/–) microbes. LsrR is a key transcriptional regulator that governs the varied downstream processes by perceiving AI-2 signal, but its activation via autoinducer-binding remains poorly understood [1]. The ligand-free crystals of LsrR and complex crystals of LsrR and C-LsrR with 5 mM R5P were grown with reservoir buffer. Complex crystal of C-LsrR/D5P and C-LsrR/D8P were obtainded by soaking the native crystals in the same crystallization buffer (pH 6.5, 0.1 M bis-tris, 9.1% PEG-3350, 10 mM barium chloride dehydrate, 10 mM R5P) containing 0.15mM D5P and 2.0 mM D8P. These crystals were determined its 3-demensional (3D) structure at 3.2 Å ~ 1.9 Å resolution after SAD phasing. The ligand-binding affinities for LsrR protein were measured using fluorescence spectrophotometer and Isothermal titration calorimetry (ITC) while increasing the ligand concentrations. Detailed regulatory mechanism of LsrR from the crystal structures in complexes with the native signal (phospho-AI-2, D5P) and two quorum quenching antagonists (ribose-5-phosphate, R5P; phosphoisobutyl-AI-2, D8P). The bound D5P and D8P molecules are not the diketone forms but rather hydrated, and the hydrated moiety forms important H-bonds with the carboxylate of D243. The D5P-binding flipped out F124 of the binding pocket, and resulted in the disruption of the dimeric interface-1 by unfolding the α7 segment. However, the same movement of F124 by the D8P'-binding did not cause the unfolding of the α7 segment. Although the LsrR-binding affinity of R5P (Kd, ~1 mM) is much lower than those of D5P and D8P (~2.0 and ~0.5 μM), the α-anomeric R5P molecule fits into the binding pocket without any structural perturbation, and thus stabilizes the LsrR tetramer. The binding of D5P, not D8P and R5P, disrupted the tetrameric structure and thus is able to activate LsrR. The detailed structural and mechanistic insights from this study could be useful for facilitating design of new anti-virulence and anti-biofilm agents based on LsrR.
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Lim, Eunhee. "The Effects of Molecular Packing Behavior of Small-Molecule Acceptors in Ternary Organic Solar Cells." Applied Sciences 11, no. 2 (January 14, 2021): 755. http://dx.doi.org/10.3390/app11020755.

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Abstract:
Herein, two diketopyrrolopyrrole (DPP)-based, small-molecule isomers, o- and p-DPP-PhCN, were introduced as acceptors in ternary organic solar cells (OSCs). The isomers have the same molecular backbone but differ in the positions of the cyanide (CN) substituents (ortho and para), which greatly affects their packing behavior. Ternary solar cells composed of poly(3-hexylthiophene) (P3HT):DPP-PhCN:phenyl-C61-butyric acid methyl ester (PCBM) were fabricated, and the effects of the different packing behaviors of the third component on the device performance and the working mechanism of the ternary cells were investigated. The addition of o-DPP-PhCN with a relatively high-lying lowest unoccupied molecular orbital energy level resulted in an increase in the open-circuit voltage (VOC) in the ternary devices, demonstrating the alloy-like structure of the two acceptors (o-DPP-PhCN and PCBM) in the ternary system. However, the p-DPP-PhCN-based ternary cells exhibited VOC values similar to that of a P3HT:PCBM binary cell, irrespective of the addition of p-DPP-PhCN, indicating a cascade energy-level structure in the ternary system and an effective charge transfer from the P3HT to the PCBM. Importantly, by increasing the addition of p-DPP-PhCN, the short-circuit current density increased substantially, resulting in pronounced shoulder peaks in the external quantum efficiency responses in the long-wavelength region, corresponding to the contribution of the photocurrent generated by the light absorption of p-DPP-PhCN. Despite sharing the same molecular backbone, the two DPP-PhCNs exhibited substantially different packing behaviors according to the position of their CN substituents, which also greatly affected the working mechanism of the ternary devices fabricated using the DPP-PhCNs as the third component.
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