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81.
Viqar Uddin Ahmad Sadia Bader Saima Arshad Amir Ahmed Afsar Khan Shazia Iqbal Munawwer Rasheed Rasool Bakhsh Tareen 《Magnetic resonance in chemistry : MRC》2010,48(4):304-308
Two new acylated flavonol glycosides, 3‐O‐{[2‐O‐β‐D ‐glucopyranosyl]‐3‐[O‐β‐D ‐glucopyranosyl]‐4‐[(6‐O‐p‐coumaroyl)‐O‐β‐D ‐glucopyranosyl]}‐α‐L ‐rhamnopyranosyl‐kaempferol 7‐O‐α‐L ‐rhamnopyranoside and 3‐O‐{2‐[(6‐O‐p‐coumaroyl)‐O‐β‐D ‐glucopyranosyl]‐3‐[O‐β‐D ‐glucopyranosyl]‐4‐[(6‐O‐p‐coumaroyl)‐O‐β‐D ‐glucopyranosyl]}‐α‐L ‐rhamnopyranosyl‐kaempferol 7‐O‐α‐L ‐rhamnopyranoside, trivially named as brauhenefloroside E (1) and F (2), respectively, were isolated from the fruits of Stocksia brauhica and their structures were elucidated using spectroscopic methods, including 2D NMR experiments. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
82.
Muhammad Safder Rashad Mehmood Bakhat Ali Uzma Rasheed Mughal Abdul Malik Abdul Jabbar 《Helvetica chimica acta》2012,95(1):144-151
Asphorins A and B ( 1 and 2 , resp.), two new triterpene glycosides, have been isolated along with a new chromone, 3 , from the AcOEt subfraction of the MeOH extract of the whole plant of Asphodelus tenuifolius. Their structures were elucidated by spectral analysis including 2D‐NMR spectroscopic experiments. 相似文献
83.
A series of new benzimidazole derivatives was synthesized and characterized by IR,1H NMR,13C NMR,MS,and HRMS spectra.All the new compounds were screened for their antimicrobial activities in vitro by a twofold serial dilution technique.The bioactive evaluation showed that 3,5-bis(trifluoromethyl)phenyl benzimidazoles were comparably or even more strongly antibacterial and antifungal than the reference drugs Chloromycin,Norfloxacin,and Fluconazole.The combination of2,4-difluorobenzyl benzimidazole derivative 5l and its hydrochloride 7 respectively with the antibacterials Chloromycin,Norfloxacin,and the antifungal Fluconazole was more sensitive to methicillin-resistant MRSA and Fluconazole-insensitive A.flavus.In addition,the interaction of compound 5l with calf thymus DNA demonstrated that this compound could effectively intercalate into DNA to form a compound 5l-DNA complex that might block DNA replication and thereby exert good antimicrobial activity. 相似文献
84.
A concise and simple synthesis of M1 allosteric agonist 1-(1′-(2-methylbenzyl)-1,4′-bipiperidin-4-yl)-1H-benzo[d]imidazol-2(3H)-one (TBPB) using economical and commercially available orthophenylenediamine (O-PDA) and Boc piperidone has been described. The disclosed scheme allows synthesizing more analogs that were otherwise difficult to prepare with the original method. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
85.
In the present study, the reaction of thiols with alkyl sulfonyl halides was carried out in a nitrogenous base to compare the reactivity of ‐SH with that of ‐OH, which, however, led to the formation of disulfides. The reaction achieved as a result offers the use of an inexpensive reagent, quantitative yields of the product, and simplicity for the formation of the S‐S bond. 相似文献
86.
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88.
A. H. K. Yousufzai A. Rasheed Khan S. Hasan Imam Z. H. Farooqui 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):381-385
The copolymerization of castor oil prepolymer (COP) was attempted with vinyl monomers in the presence of a free radical initiator at 75°C. It was found that acrylonitrile copolymerizes with COP in good yield, The copolymers were yellow brown in color and were soluble in hot dimethylformamide. The percentage composition of the copolymers was determined by the nitrogen of the copolymers. Their reactivity ratios were determined to be r1 = 0.53, r2 = 1.53. 相似文献
89.
A study of copolymerization of castor oil prepolymers (COP) with styrene has been made at 75°C using benzoyl peroxide as initiator. It has been found that good yields of copolymers (high molecular weight M n = 123,989) are obtained at a low concentration of COP. With an increasing concentration of COP in the binary mixture, copolymers with decreasing molecular weight are obtained. This is explained as due to presence of a high percentage of oxygen (from COP) in the system which is acting as a chain transfer agent. 相似文献
90.
The CH local mode overtone spectrum of benzyl chloride in the visible and NIR regions studied by laser induced thermal lens
and conventional NIR absorption is presented. The analysis shows that the −CH2Cl group is symmetrically oriented with respect to the benzene ring, thus finalizing one of the two possible conformational
models predicted by electron diffraction studies. The aryl CH bonds have a slightly larger force constant than that in benzene. 相似文献