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61.
Ranjan Patra Israel Goldberg 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(8):819-821
The synthesis is reported of the tricarboxylic acid 3‐(3,5‐dicarboxybenzyloxy)benzoic acid (H3L) and the product of its reaction under solvothermal conditions with ZnII cations, namely poly[[μ6‐3‐(3,5‐dicarboxylatobenzyloxy)benzoato](dimethylformamide)‐μ3‐hydroxido‐dizinc(II)], [Zn2(C16H9O7)(OH)(C3H7NO)]n, the formation of which is associated with complete deprotonation of H3L. Its crystal structure consists of a single‐framework coordination polymer of the organic L3− ligand with ZnII cations in a 1:2 ratio, with additional hydroxide and dimethylformamide (DMF) ligands coordinated to the ZnII centres. The ZnII cations are characterized by coordination numbers of 5 and 6, being bridged to each other by hydroxide ligands. In the polymeric framework, the carboxylate‐ and hydroxy‐bridged ZnII cations are arranged in coordination‐tessellated columns, which propagate along the a axis of the crystal structure, and each L3− ligand links to seven different ZnII centres via Zn—O bonds of two different columns. The coordination framework, composed of [Zn2(L)(OH)(DMF)]n units, forms an open architecture, the channel voids within it being filled by the zinc‐coordinating DMF ligands. This report provides the first structural evidence for the formation of coordination polymers with H3L via multiple metal–ligand bonds through its carboxylate groups.<!?tpb=21.5pt> 相似文献
62.
6-Alkylpyrano [3,2-c] quinolin-5(2H)-ones(11a-e) were obtained in excellent yields by simply refluxing propynyl and butymyl ethers (6) of 4-hydroxy-1-alkylquinolin-2H-ones (2) in chlorobenzene for 10h, 5-Prop-2-ynyloxy-2H-pyrano [3,2-c] quinoline (12) was also obtained from the thermal rearrangement of 2,4-bis prop-2-ynyloxyquinoline (4). 相似文献
63.
A simple and efficient method for the convenient synthesis of 2-arylbenzimidazole has been described on reaction with o-phenylenediamine and various aromatic aldehydes using cobalt(II) chloride hexahydrate as a catalyst. The method is cost-effective, high-yielding, clean, and selective. 相似文献
64.
An expedient three‐step procedure for the synthesis of trichlorophenol derivatives based on the acid‐catalyzed rearrangement of the bicyclic ketone precursors 6a–e in high overall yield is described. The bicyclic ketone precursors 6a–e were obtained from Diels–Alder cycloadducts of β‐substituted vinyl acetates with tetrachloro‐5,5‐dimethoxycyclopentadiene in two steps. 相似文献
65.
Sitaram Pal Sukumar Ghosh Bimal K. Banik Shaikh Khairul Alam Usha Ranjan Ghatak 《合成通讯》2013,43(14):2203-2216
The bridged-ethers, (±)-2-methoxy-9a-carbamorphinan (1b) and (±)-2-methoxy-9a-carba-14α-morphinan(2b) have been synthesized. The acid-catalyzed cyclizations of 1-m-methoxy benzyloctalone 3b and 1-m-methoxybenzyloctalins 4b proceed with high regio-and stereoselectivities leading mostly to the bridged-ketone 14 and ether 1b respectively, along with o-methoxy-tetracyclic ketone 15 and the ether 17, in addition to other minor products. 相似文献
66.
Madhumanchi Sreenu Rati Ranjan Nayak Yedla Poornachandra C. Ganesh Kumar 《Journal of Dispersion Science and Technology》2013,34(6):765-771
Synthesized sodium N-pamitoyl amino acids were evaluated for surface and antimicrobial properties and compared with sodium lauryl sulfate (SLS). Emulsion stability of the amino acid surfactants and calcium tolerance of the sodium N-palmitoyl isoleucine were better as compared to SLS. Wetting ability and foaming properties of the palmitic acid-based surfactants were inferior to SLS. N-Acyl amino acids exhibited better antibacterial activity compared to sodium salts of N-acyl amino acids and standard compounds against Staphylococcus aureus MLS-16 and Bacillus subtilis. These studies revealed that the palmitoyl amino acid surfactants can be exploited in household, skin care formulations, and industrial applications. 相似文献
67.
Bikash Ranjan Sahoo Banikalyan Swain Manas Ranjan Dikhit Madhubanti Basu Aritra Bej Pallipuram Jayasankar Mrinal Samanta 《Applied biochemistry and biotechnology》2013,170(6):1282-1309
The nucleotide-binding oligomerization domain 1 (NOD1) receptor recognizes various pattern-associated structures of microbes through its leucine-rich repeat (LRR) domain and activates signaling cascades to induce innate immunity. This report describes the activation of NOD1 receptor signaling by gamma-d-glutamyl-meso-diaminopimelic acid (or γ-D-Glu-mDAP [iE-DAP]) in a commercially important fish species, rohu (Labeo rohita). It also described critical motifs in the NOD1-LRR domain that could be involved in binding iE-DAP, lipopolysaccharide (LPS), and polyinosinic:polycytidylic acid (poly I:C). The activation of NOD1 receptor signaling was studied by injecting iE-DAP, and analysis of tissue samples for NOD1 and receptor-interacting serine/threonine kinase (RICK) expression was done by quantitative real-time polymerase chain reaction (qRT-PCR) assay. To identify ligand-binding motifs in NOD1, the 3D model of NOD1-LRR was generated, followed by a 6-ns molecular dynamics simulation. Molecular docking of LPS with NOD1-LRR was executed at the Hex and PatchDock servers, and iE-DAP and poly I:C in the AutoDock 4.2, FlexX 2.1, Glide 5.5, and GOLD 4.1 programs. The results of qRT-PCR revealed significant (p?<?0.05) upregulation of NOD1 and RICK expression. Molecular docking revealed that the amino acid residues at LRR1–2, LRR3–7, and LRR8–9 could be involved in poly I:C, LPS, and iE-DAP binding, respectively. In fish, this is the first report describing the 3D structure of NOD1-LRR and its critical ligand-binding motifs. 相似文献
68.
Zahra Afrasiabi Rosana Almudhafar Di Xiao Ekkehard Sinn Amitava Choudhury Aamir Ahmad Alok Vyas Fazlul Sarkar Subhash Padhye 《Transition Metal Chemistry》2013,38(6):665-673
A planar, polycyclic and aromatic hydrocarbon ligand, namely 9,10-phenanthrenequinone semicarbazone, and its transition metal complexes have been synthesized and structurally characterized. The in vitro antiproliferative activity of these compounds against five human cancer cell lines revealed that they were effective against androgen receptor-positive/negative prostate cancer cells as well as COX-positive pancreatic BxPC-3 cancer cell line. The driving force behind such antiproliferative activity seems to be the up-regulated COX expression in these cells, which was amenable for targeting through metal complexation. These structural motifs can, therefore, serve as a starting point for developing novel cytotoxic agents against the growing number of prostate and pancreatic cancers. 相似文献
69.
Ambar Kumar Choudhury Asim Kumar Ray Nirmolendu Roy 《Journal of carbohydrate chemistry》2013,32(8):1153-1163
Abstract Starting from L-fucose, D-glucose and lactose, methyl O-[2,3-di-O-benzoyl-4, 6-O-(4-methoxybenzylidene)-β-D-glucopyranosyl]-(1→4)-2,3-di-O-benzoyl-α-L-fucopyranoside and methyl O-(2,3,4,6-tetra-O-benzyl-β-D-galactopyranosyl)-(1→4)-O-(2,3,6-tri-O-benzyl-α-D-glucopyranosyl)-(1→4)-O-(methyl 2,3-di-O-benzoyl-β-D-glucopyranosyluronate)-(1→4)-2,3-di-O-benzoyl-α-L-fucopyranoside were synthesized. Removal of protecting groups gave the tetrasaccharide repeating unit of the antigen from Klebsiella type-16 in the form of its methyl ester methyl glycoside. 相似文献
70.
A tandem approach for the regio- and stereoselective synthesis of oxazolo-fused pyrroloquinolines 3a–l via the reaction of o-alkynylaldehydes 1a–i with chiral amino alcohols 2a–c under mild reaction conditions is described. The possible participation of the pyridine ring in the regioselective formation of 5-exo-dig cyclized products was supported by the controlled experiments. The structures and stereochemistry of the products were confirmed by NOESY and X-ray crystallographic studies. 相似文献