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91.
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
92.
Reforming of dimethyl ether with carbon dioxide into synthesis gas has been carried out over a mixed catalyst containing Cu-based methanol decomposition catalyst and alumina. The catalyst is found to show a high activity and selectivity. Catalyst stability and deactivation mechanism was also examined. 相似文献
93.
A bis-reactive cationic fixing agent, ethylenebis[N-(2,3-epoxypropyl)-N,N-dimethylammonium chloride] has been used as an aftertreatment reagent to improve the wash fastness of direct dyes on cotton. The effects of different pH conditions and concentrations on the effectiveness of this cationic fixing agent have been investigated. The results showed that aftertreatment at pH 11 produced dyeings with higher colour strength and better wash fastness than that at pH 7. In addition, the cationic agent at a low concentration was found to be more effective under both neutral and alkaline conditions. 相似文献
94.
95.
A novel aromatic triol was synthesized and polycondensed with various diacid chlorides resulting in the preparation of a series of hydroxy-terminated hyperbranched polyamide-esters without gelation. Structure and degree of branching of the ensuing polymers were confirmed by FTIR, 1H and 13C NMR analyses. These thermally stable polymers were found to be soluble in aprotic solvents. Inherent viscosities and Tg values lie in the range of 0.15-0.21 dL/g and 74-112 °C, respectively. 相似文献
96.
Rizwana Zahoor Samina Roohi Mushtaq Ahmad Zafar Iqbal Nagina Amir Saima Tariq Paul. B. Savage 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):841-844
Ceragenins/cationic steroid antimicrobials (CSAs) are a group of cholic acid derivatives with many properties that make them favourable for application as anti-infective agents. CSA-107 is also a member of this group that was labelled with 99mTc by using SnCl2·2H2O as reducing agent and Na–K tartrate as transchelating agent. Labelling efficiency was optimized by varying the amount of reducing agent, pH, and time of incubation. Labelling efficiency and the stability of 99mTc-CSA-107 in human serum was determined by paper and thin layer chromatography, which were >95 and >90 % respectively. In vitro binding of 99mTc-CSA-107 was >95 % determined by using Staphylococcus aureus bacteria. 相似文献
97.
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
98.
Carboxylic acid terminated aromatic and semiaromatic hyperbranched polyamide-esters (HBPAEs) containing pyrimidine moieties were prepared by polycondensation of 4-hydroxy-2,6-diaminopyrimidine (CBB′) to a double molar ratio of various diacid chlorides (A2) without any catalyst. The products were soluble in organic solvents, such as N,N-dimethylformamide, N-methyl-2-pyrrolidone and displayed glass transition temperature (Tg) between 180 and 244 °C. The polymerization products have been investigated with FTIR, 1H and 13C NMR analyses and the degree of branching was higher than 60%. Amorphous polymers had inherent viscosity (ηinh) ranging between 0.21-0.28 dL/g and had excellent thermal stability with 10% weight loss at 346-508 °C. 相似文献
99.
Javid Hussain Meamoona Munir Zahid Hassan Naseem Bano Saima Arshad Viqar Uddin Ahmad 《Helvetica chimica acta》2010,93(2):350-353
One new ceramide (=long‐chain base linked to a fatty acid via an amide bond), tanacetamide D ( 1 ), was isolated from Tanacetum artemisioides. Besides this, the two known constituents 5‐demethylnobiletin ( 2 ) and 5‐hydroxy‐3,6,7,8,3′,4′‐hexamethoxyflavone ( 3 ) were isolated for the first time from this species. The structure elucidation of the isolated compounds were based primarily on 2D‐NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple‐quantum coherence (HMQC), heteronuclear multiple‐bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY) experiments. 相似文献
100.
Abdul Wajid Khan Saleem Jan Shaista Parveen Rahmat Ali Khan Asma Saeed Abdul Jabbar Tanveer Anwar Ali Shad 《Chemistry Central journal》2012,6(1):1-6