The fifth solvatomorph of gallic acid with a supramolecular channel structure: Structural complexity and phase transitions

A new solvatomorph of gallic acid was generated using chiral additive technique and characterized by single crystal and powder X-ray diffraction, C-13 NMR, IR spectroscopic techniques and thermal analysis. The supramolecular channels formed by hexameric motifs of gallic acid and solvent molecules contain highly disordered solvent molecules with fractional occupancies. © 2012 Elsevier B.V.

Design and synthesis of positional isomers of 5 and 6-bromo-1-(phenyl)sulfonyl]-2-(4-nitrophenoxy)methyl]-1H-benzimida zoles as possible antimicrobial and antitubercular agents

In this Letter, we report the structure activity relationship (SAR) studies on series of positional isomers of 5(6)-bromo-1-(phenyl)sulfonyl]-2-(4-nitrophenoxy)methyl]-1H-benzim idazoles derivatives 7(a-j) and 8(a j) synthesized in good yields and characterized by H-1 NMR, C-13 NMR and mass spectral analyses. The crystal structure of 7a was evidenced by X-ray diffraction study. The newly synthesized compounds were evaluated for their in vitro antibacterial activity against Staphylococcus aureus, (Gram-positive), Escherichia coil and Klebsiella pneumoniae (Gram-negative), antifungal activity against Candida albicans, Aspergillus flavus and Rhizopus sp. and antitubercular activity against Mycobacterium tuberculosis H37Rv, Mycobacterium smegmatis, Mycobacterium fortuitum and MDR-TB strains. The synthesized compounds displayed interesting antimicrobial activity. The compounds 7b, 7e and 7h displayed significant activity against Mycobacterium tuberculosis H37Rv strain.

Isolation and characterization of biofumigant from leaves of Lantana camara for control of stored grain insect pests

Due to environmental concerns, health hazards to man and the evolution of resistance in insect pests, there have been constant efforts to discover newer insecticides both from natural sources and by chemical synthesis. Natural sources for novel molecules hold promise in view of their eco-friendly nature, selectivity and mammalian safety. We have isolated one natural bioactive molecule from the leaves of Lantana camara named Coumaran, based on various physical-chemical and spectroscopic techniques (IR, H-1 NMR, C-13 NMR and MS). Coumaran is highly toxic and very low concentration is needed for control of stored product insects. This molecule has potent grain protectant potential and caused significant reduction in F1 progeny of all the three species in the treated grain and the progeny was completely suppressed at 30 mu g/l. The differences in germination between the control and treated grains were not significant. The lack of any adverse effect of Coumaran on the seed germination is highly desirable for a grain protectant, becoming a potential source of biofumigant for economical and environmentally friendly pest control strategies against stored grain pests during storage of grains or pulses. (C) 2013 Elsevier B.V. All rights reserved.

Novel 2,6-bis(4-methoxyphenyl)-1-methylpiperidin-4-one oxime esters: synthesis and a new insight into their antioxidant and antimicrobial potential

A simple and efficient protocol for the synthesis of novel 2,6-bis(4-methoxyphenyl)-1-methylpiperidin-4-one oxime esters 4(a-q) is described. Initially, p-anisaldehyde 1 was condensed (Mannich reaction) with acetone and ammonium acetate trihydrate afforded 2,6-bis(4-methoxyphenyl)piperidin-4-one 2. Then, methylation followed by oximation with hydroxylamine hydrochloride (NH(2)OHa (TM) HCl) furnished a key scaffold 4. Further, to explore the enhanced biological properties of the piperidin-4-one core i.e. the key scaffold 4 was conjugated with substituted benzoyl chlorides in the presence of anhydrous K2CO3 as base to obtain novel 2,6-bis(4-methoxyphenyl)-1-methylpiperidin-4-one oxime esters 4(a-q) in excellent yields. The newly synthesized compounds were characterized by elemental analysis, IR, H-1 NMR, C-13 NMR and mass spectroscopic techniques, and screened for their in vitro antioxidant and antimicrobial activities. Most of the compounds exerted positive efficacy towards the biological assays performed. Among the synthesized analogues, compounds 4l and 4m exhibited promising antioxidant activity and on the other hand compounds 4b and 4d manifested persuasive antibacterial activity, whereas compound 4b displayed stupendous antifungal activity against A. flavus strain.

Synthesis and antiproliferative effect of novel 4-thiazolidinone-, pyridine- and piperazine-based conjugates on human leukemic cells

The present work reveals the synthesis and antiproliferative effect of a series of 2, 3 disubstituted 4-thiazolidinone analogues on human leukemic cells. The chemical structures of newly synthesized compounds were confirmed by IR, H-1 NMR, C-13 NMR and mass spectral analysis. Compound methyl 3-methoxy-4-(4-oxo-3-(5-(piperazin-1-yl)pyridin-2-yl)thiazolidin-2-yl)be nzoate (5) displayed potent activity (IC50 9.71, 15.24 and 19.29 mu M) against Nalm6, K562, Jurkat cells. Cell cycle analysis and mitochondrial membrane potential further confirmed that compound 5 is cytotoxic and able to induce cell death. (C) 2014 Elsevier Masson SAS. All rights reserved.

Synthesis, DNA binding, docking and photocleavage studies of quinolinyl chalcones

A series of simple quinoline-chalcone conjugates have been synthesized by Claisen-Schmidt condensation reactions of substituted acetophenones with 2-chloro-3-formyl-quinoline and evaluated for their nucleolytic activity. The structures of the synthesized quinoline-chalcone conjugates were confirmed by IR, H-1 NMR, C-13 NMR and mass spectral analyses. Most of the prepared compounds showed significant DNA binding and photocleavage activities. The incorporation of an electron-donating group into ring A caused a moderate increase in the DNA binding and photocleavage activities. Compounds 3c and 3d exhibited promising DNA photocleavage against pUC 19 DNA with 85% inhibition at 100 mu M concentration. A structure-activity relationship analysis of these compounds was performed; compounds 3c and 3d are potential candidates for future drug discovery and development.

Phenyl carbohydrazone conjugated 2-oxoindoline as a new scaffold that augments the DNA and BSA binding affinity and anti-proliferative activity of a 1,10-phenanthroline based copper(II) complex

A new type of copper(II) complex, CuL(phen)(2)](NO3) (CuIP), where L ((E)-N'-(2-oxoindolin-3-ylidene) benzohydrazide) is a N donor ligand and phen is the N, N-donor heterocyclic 1,10-phenanthroline, has been synthesized. The phenyl carbohydrazone conjugated isatin-based ligand L and CuIP were characterized by elemental analysis, infrared, UV-Vis, H-1 and C-13 NMR and ESI-mass spectral data, as well as single-crystal X-ray diffraction. The interaction of calf thymus DNA (CT DNA) with L and CuIP has been investigated by absorption, fluorescence and viscosity titration methods. The complex CuIP displays better binding affinity than the ligand L. The observed DNA binding constant (K-b = 4.15(+/- 0.18) x 10(5) M-1) and binding site size (s = 0.19), viscosity data together with molecular docking studies of CuIP suggest groove binding and/or a partial intercalative mode of binding to CT DNA. In addition, CuIP shows good binding propensity to the bovine serum albumin (BSA) protein, giving a K-BSA value of 1.25(+/- 0.24) x 10(6) M-1. In addition, the docking studies on DNA and human serum albumin (HSA) CuIP interactions are consistent with the consequence of binding experiments. The in vitro anti-proliferative study establishes the anticancer potency of the CuIP against the human cervical (HeLa) and breast (MCF7) cancer cells; noncancer breast epithelial (MCF10a) cells have also been investigated. CuIP shows better cytotoxicity and sensitivity towards cancer cells over noncancer ones than L under identical conditions, with the appearance of apoptotic bodies. (C) 2014 Elsevier B.V. All rights reserved.

Synthesis, molecular docking and anti-mycobacterial evaluation of new imidazo1,2-a]pyridine-2-carboxamide derivatives

New anti-tubercular agents, imidazo1,2-a]pyridine-2-carboxamide derivatives (5a-q) have been designed and synthesized. The structural considerations of the designed molecules were further supported by the docking study with a long-chain enoyl-acyl carrier protein reductase (InhA). The chemical structures of the new compounds were characterized by IR, H-1 NMR, C-13 NMR, HRMS and elemental analysis. In addition, single crystal X-ray diffraction has also been recorded for compound 5f. Compounds were evaluated in vitro against Mycobacterium tuberculosis H37Rv, and cytotoxicity against HEK-293T cell line. Amongst the tested compounds 5j, 5l and 5q were emerged as good anti-tubercular agents with low cytotoxicity. The structure-anti TB activity relationship of these derivatives was explained by molecular docking. (C) 2014 Elsevier Masson SAS. All rights reserved.

Synthesis, ABTS-Radical Scavenging Activity, and Antiproliferative and Molecular Docking Studies of Novel Pyrrolo1,2-a]quinoline Derivatives

A new 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)-radical scavenging and antiproliferative agents of pyrrolo1,2-a]quinoline derivatives have been synthesized. An efficient method for the synthesis of 14 novel diversified pyrrolo1,2-a]quinoline derivatives has been described using 4-(1,3-dioxolan-2-yl)quinoline and different phenacyl bromides in acetone and followed by reacting with different acetylenes in dimethylformamide/K2CO3. The structure of the newly synthesized compounds was determined by infrared, H-1 NMR, C-13 NMR, mass spectrometry, and elemental analysis. The in vitro antioxidant activity revealed that among all the tested compounds 5n exhibited maximum scavenging activity with ABTS. Compound 5b has showed good antiproliferative activity as an inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase.

New rotenoids from roots of Mirabilis jalapa

Four new rotenoids named mirabijalone A-D-1) (1-4), together with 9-O-methyl-4-hydroxyboeravinone B (5), boeravinone C (6) and F (7), and 1,2,3,4-tetrahydro-1-methylisoquinoline-7,8-diol (8), were isolated from the roots of Mirabilis jalapa. The structures of these compounds were determined on the basis of their HR-EI-MS, IR, UV, H-1- and C-13-NMR (DEPT). and 2D NMR (HMQC, HMBC, NOESY) data. Among them, 1,2,3,4-tetrahydro-1-methylisoquinoline-7,8-diol (8) showed a 48% inhibition against HIV-1 reverse transcriptase at 210 mug/ml.

有机化合物结构解析专家系统研究从二维连接表生成分子结构图

有机化合物结构解析专家系统的研究一直是计算机化学领域的前沿课题．在ESESOC系统已有的基础上，进行了从二维连接表生成分子结构图的研究，程序可从化合物的二维连接表出发，生成化合物的分子结构图．从二维连接表生成的分子结构图必须满足以下要求：美观而且符合化学家的习惯，生成的效率要高，一个美观的分子结构式必须做到以下几点：环能容易被人识别；一般情况下键一长应该一致；链上的原子之间无重叠，也不拥挤；完整的结构应有正确的取向，如烷烃的最长链保持水平，且相似的结构应该有相同的取向．从二维连接表生成的分子结构图是一个非常复杂的过程，涉及到图论，几何学，化学，以及计算机多方面的知识．所以尽管有很多方法可以用来生成分子结构图，但是还没有一种非常完美的办法．本工作在这些已有方法中选取了一种方法，同时结合其他方法对之进行了改进，并在计算机上编程实现了这种方法，最终得到一个能从分子的二维连接表生成美观的分子结构图的程序．Internet为科学研究提供了巨大的便利．本工作利用XML技术，实现了网上分子结构数据中分子结构的动态显示；利用ASP技术实现了网上C-13-NMR谱图数据库相似检索．

“PP-PE”聚合合金结构与性能的关系及PP/HDPE共混体系增容改性的新途径

试图澄清“PP-PE”结构与性能的关系，并以此为指导寻求增容改性PP/HDPE体系的新途径是本工作的主要内容。在本工作中，考虑到分子量、EPC组分和共混均匀性因素之后发现，“PP-PE”与相同条件下合成的均聚物样品构成的共混物之间在应力-应变行为、抗冲击性能和动态力学行为上并没有明显差别。在结合文献中有关现象详尽讨论了关于活性链寿命报导值和“（PP-PE）_(200)"的C~(13)NMR谱支持嵌段结构观点的可靠性之后，得到的结论是，现有实验现象不中以证明“PP-PE”具有嵌段结构，尽管四十年来这一观点已被普遍接受。通过TEM观察到，“PP-PE”与PP/HMWPE共混物结晶结构相同，“PP-PE”中的PE部分明显具有HMWPE的片晶特征，应力-应变和SEM实验的结果显示，“PP-PE”与HMWPE具有完全相同的增容PP/HDPE的作用。结合有关共混物结构和性能的实验结果，发现“PP-PE”主要是一个共混物，其中的HMWPE和EPC组分是决定其性能行为的主要因素。尽管在理论和实验上都已确认，分子量的增大不利于共混物组分间的相容，但通过应力-应变实验和形态结构的观察发现，虽然均聚物HMWPE的加入使PP/HDPE体系中PE组分平均分子量增大，但是体系中分散相尺寸却随HMWPE含量的增加大幅度减小，力学性能全面提高。HMWPE这种同接枝和嵌段共聚相似的增容作用既不能用“相似相容”，也不能用所谓“特殊相互作用”来阐明。为此，在本工作中提出了一个新的增容机制——“缠结作用”。应力-应变实验表明，PP/HMWPE体系的力学性能明显优于PP/HDPE体系。前者强度和断裂伸长率都高于后者，其差别尤以断裂伸长率为甚，而模量相差不大。SEM形态结构的观察发现，虽然PP/HDPE体系中的分散相尺寸随其量的增加而增大，并且界面清晰，但PP/HMWPE中的缠结作用使得组分间界面模糊，甚至消失。这种较强的组分间相互作用使得材料由脆性断裂转变为韧性断裂。PP/HMWPE的性能特点进一步证实了非理想换气条件下制备的“PP-PE”结构与性能的关系。

A simple preparation of stationary phase of alkylamide reversed-phase liquid chromatograph for the separation of basic substances

A simple preparation process of alkylamide phase for reversed-phase HPLC (RP-HPLC) is described. The process includes aminopropyltrimethoxysilane firstly reacted with octanoyl chloride, then the intermediate was coupled onto porous silica. The resultant bonded silica has a reproducible ligand surface concentration and homogenous bonded ligand distribution on the porous silica. Characterization of prepared packing was carried out with elemental analysis, solid-state C-13 NMR and Fourier transform infrared (FT-IR). Chromatographic evaluations were carried out by using a mixture of organic compounds including acidic, basic and neutral analytes under methanol/water as binary mobile phase. The results showed that the stationary phase have excellent chromatographic properties and can be efficiently used for the separation of basic compounds.

Structure of an unexpected trimer from the reaction of ageratochromene II with aluminum chloride

A new trimer from the reaction of ageratochromene [1] (6,7-dimethoxy-2,2-dimethyl-1-benzopyran) with anhydrous aluminum chloride was shown to be 3,4-dihydro-6,7-dimethoxy-2,2-dimethyl-3-(6',7'-dimethoxy-2',2'-di-methyl-2H-1-benzopyran-4'-yl)-4-(3" 4"-dihydro-6", 7"-dimethoxy-2",2"-dimethyl-2H-1-benzopyran-3"-yl)-2H-1-benzopyran. Its structure was confirmed by NMR (H-1, C-13, DEPT-135. COSY, HMBC, HSQC, TOCSY and NOESY), IR, mass spectra and elemental analysis. Copyright (C) 2002 John Wiley Sons, Ltd.

Solution-processable highly efficient yellow- and red-emitting phosphorescent organic light emitting devices from a small molecule bipolar host and iridium complexes

A bipolar transport compound, 2,5-bis(4-(9-(2-ethylhexyl)-9H-carbazol-3-yl) phenyl)-1,3,4-oxadiazole (CzOXD), incorporating both electron-and hole-transport functionalities, was synthesized and fully characterized by H-1 NMR, C-13 NMR, elemental analysis and mass spectrometry. Its thermal, electrochemical, electronic absorption and photoluminescent properties were studied