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排序方式: 共有382条查询结果,搜索用时 15 毫秒
31.
Dr. Ramasamy Jayarajan Tautvydas Kireilis Prof. Lars Eriksson Prof. Kálmán J. Szabó 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(58):e202202059
A broad range of aliphatic, aromatic, and heterocyclic boronic acids were successfully homologated using trifluorodiazoethane in the presence of BINOL derivatives to provide the corresponding chiral trifluoromethyl containing boronic acid derivatives in high yields and excellent enantioselectivity. The in situ conversion of the chiral transient boronic acids to the corresponding alcohols or β-CF3 carboxylates are also demonstrated. 相似文献
32.
Shanmugam Kotteswaran Sundaramoorthy Kannadhasan Perumalsamy Ramasamy 《Journal of Solid State Electrochemistry》2021,25(7):1949-1958
Journal of Solid State Electrochemistry - The phenyl-conjugated oligoene dye 2-cyano3-(4-diphenylaminophenyl)prop-2-enoic acid (SKS) was synthesized by chemical method, and its structure was... 相似文献
33.
Khadhar Navaz Umar Basha Shanthi Gnanamani Prakash Shanmugam Sujatha Venugopal Sangeetha Murthy Balagurunathan Ramasamy 《Journal of heterocyclic chemistry》2021,58(10):2000-2008
A simple and convenient method for the one-pot synthesis of 3-(1H-indole-3-carbonyl)-2H-chromen-2-one derivatives from the reaction of 3-cyanoacetyl indole and salicylaldehyde in the presence of Na2CO3 in water: methanol (1:1) is described. Wider substrate scope, high yields, operational simplicity, and simple purification process make the protocol highly applicable in the synthesis of 3-(1H-indole-3-carbonyl)-2H-chromen-2-ones. For the first time, in vitro antioxidant and antimicrobial activity was studied. Compounds 5e , 7a , and 7b exhibits good radical scavenging ability against DPPH free radical. Compounds 7b , 5f , and 5g possess lower EC50 values than the Standards AA and BHA and thus proving their high reducing power. Compounds 5d and 5f show good antibacterial activity against gram-positive bacteria (MRSA) while compounds 5c , 7a , and 7b exhibits good antibacterial activity against Bacillus sp. Compounds 5b and 5e show good antibacterial activity against gram negative bacterial strains (Escherichia coli, Klebsiella pneumoniae) and compounds 5g and 5h exhibits good antifungal activity against Candida albicans. 相似文献
34.
The influence of concentration, ageing and pH of the gel medium on the periodic precipitation of cobalt oxinate in agar gel
is reported. The results are explained on the basis of Shinohara’s revised flocculation theory. The flocculation value (F) increases with increase in the gel concentration whereas it decreases with increase in ageing and pH of the gel. The raise
in temperature of the gel increases the solubility of the sparingly soluble substance and hence theF value. The effect of additives on the periodic precipitation of cobalt (II) oxinate is reported. 相似文献
35.
The oxidation of aniline in glacial acetic acid with percarbonate, a dry carrier of hydrogen peroxide, is a second-order reaction conforming to the isokinetic relationship. The hitherto followed method of correlation of the reaction rates in terms of the structure-reactivity relationships is unsatisfactory and erroneous. But the reaction rates of molecular anilines, obtained for the first time, conform to the structure-reactivity relationships. 相似文献
36.
37.
2-Amino-2,4-anhydro-psicofuranose derivative was synthesized starting from d-fructose. 相似文献
38.
Sreeram Kalarical Janardhanan Indumathy Ramasamy Balachandran Unni Nair 《Transition Metal Chemistry》2008,33(1):127-131
Natural polymers like chitosan and starch have been employed as templates for the preparation of iron oxide nanoparticles.
The templates offer selective binding sites for Fe(II) under aqueous conditions. Controlled drying and subsequent removal
of the template backbone enables the synthesis of spatially separated iron oxide nanoparticles. The crystalline character
of the iron oxide and near narrow particle size distribution pattern have been confirmed through powder XRD, Photon Correlation
Spectroscopy, and TEM measurements. The crystallite sizes of the particles were found to be 26–35 nm irrespective of the nature
of the template. 相似文献
39.
Namasivayam Subhapradha Ramachandran Saravanan Pasiyappazham Ramasamy Alagiri Srinivasan Vairamani Shanmugam Annaian Shanmugam 《Applied biochemistry and biotechnology》2014,172(1):9-20
Chitosan has attracted much attention as a biomedical material, owing to its unique biological activities. In this study, hepatoprotective effect of β-chitosan obtained from the gladius of squid Sepioteuthis lessoniana was studied against carbon tetrachloride (CCl4)-induced oxidative stress and liver injury in rats. The rats that received β-chitosan along with the administration of CCl4 showed significantly decreased plasma and tissue alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and total cholesterol, triglyceride (TG) and free fatty acid (FFA) contents, whereas the treatment with β-chitosan alone markedly increased rat hepatic and circulatory superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) and reduced glutathione (GSH) levels and decreased the malondialdehyde level. Histopathological observations recommended the marked hepatoprotective effect of β-chitosan. The CCl4-induced alterations on circulatory and hepatic antioxidant defence system were normalised by β-chitosan, and it could be concluded that the hepatoprotective effect of chitosan may be due to its antioxidant and antilipidemic property. Therefore, β-chitosan could be considered as antihepatotoxic agent. 相似文献
40.