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111.
Generation of carbon‐metal species is extremely important in transition metal‐catalyzed organic synthesis. Among the various methods, 1,4‐metal migration is a very useful way to create new carbon‐metal species, which are not readily accessible via classic methods. This review summarized recent advances in transition metal‐catalyzed reactions, which involved one or more steps of 1,4‐metal migration. It focused mostly on the achievements in Pd and Rh‐catalyzed reactions, along with some of the remarkable results in Pt, Ir, Co, Fe‐involved transformations. 相似文献
112.
Spectral studies of morin in aqueous ethanol and other alcohols have been carried out as a function of its concentration and that of ethanol, and the pH of aqueous buffer. The effect of gamma radiations on morin solution in ethanol was also studied as a function of dose in the range of 0.15–2.28 kGy and of morin concentration (10–5–10–4 mole·dm–3). Morin concentration in ethanol solution showed a linear response for G values to a dose of 1.83 kGy. Molar absorption coefficients () for morin in ethanol have been estimated to be
260nm=2.28·104 dm3·mol–1·cm–1 and
291nm=8.22·103 dm3·mol–1·cm–1 for unirradiated and
291 nm=1.75·104 dm3·mol–1·cm–1 for irradiated solutions to a dose of 1.83 kGy. 相似文献
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Wahid Zada Sara Zeeshan Huma Aslam Bhatti Wajahat Mahmood Khalid Rauf 《Natural product research》2016,30(10):1212-1214
The aim of the study was to explore the traditional use of Cinnamomum cassia against depression. The standardised methanolic extract of the bark of C. cassia was evaluated for antidepressant activity using various behavioural tests, i.e. tail suspension test (TST), forced swim test (FST) and locomotor activity test. The serotonergic and noradrenergic modulation was assessed using 5-hydroxytryptophan (5-HTP)-induced head twitches and yohimbine potentiation tests, respectively. The fluoxetine and phenelzine were used as positive controls in the study. The C. cassia extract significantly decreased the immobility time in TST (maximum effective dose tested was 50 mg/kg) while no effect was observed in FST and locomotor activity test. The extract significantly increased the 5-HTP-induced head twitches while yohimbine-induced lethality remained unaltered. The aforementioned results are similar to that caused by fluoxetine. The standardised methanolic extract of C. cassia demonstrated antidepressant activity that can be attributed to rise in serotonin levels. 相似文献
117.
Rasool Khan Abdullah Qasem Saif Mohammad Mansour Quradha Jawad Ali Abdur Rauf 《Natural product research》2015,29(5):466-468
In this paper we report the antimicrobial, antiradical and urease inhibitory potential along with photochemical investigation of the crude extracts of Cyphostemma digitatum Lam. Phytochemical screening of both the crude (hot/cold) alcoholic and aqueous extracts of C. digitatum showed the presence of alkaloids, flavonoids, saponins, coumarins, steroids, terpenoids and tannins. The crude methanolic extract (hot/cold) exhibited good antioxidant activity, while the aqueous extract was a weak antioxidant. The crude methanolic extract was found to be more active against Bacillus subtilis, while both the extracts showed moderate antifungal potential, the methanolic crude extract showed good urease inhibitory activity compared with the aqueous crude extract. 相似文献
118.
Saloni Gangal Shweta Sharma Abdul Rauf 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):242-259
A microwave-assisted combinatorial synthesis of 2-long alkenyl chain benzoxazoles and naphtho[2,3-d]oxazoles with a catalytic amount of phosphorus pentasulphide at ambient pressure has been developed. This procedure constitutes a simple, practical, and green synthetic method for benzoxazoles and their structural analogs. All the compounds [2(a–d) through 6(a–d)] have been screened for antibacterial and antifungal activity. The compounds have showed good activity against Gram-positive and Gram-negative bacteria. All the compounds have also showed good results against almost all fungal strains. The structures of the synthesized compounds are elucidated by IR, 1H NMR, 13C NMR, MS data, and elemental analysis. 相似文献
119.
Sohaila Andleeb Imtiaz‐ud‐Din Muhammad Khawar Rauf Syed Sikander Azam Ihsan‐ul Haq Muhammad Nawaz Tahir Sajjad Ahmad 《应用有机金属化学》2019,33(9)
Heteroleptic triorganobismuth (V) complexes of general formula, R3Bi(OOCR')2 ( 1 – 7 ), where R = C6H5 ( 1 – 3 ), p‐CH3C6H4 ( 4 – 7 ) and R' = 3,5‐Cl2C6H3 ( 1 , 5 ); 3,4,5‐(OCH3)3C6H2 ( 2 , 6 ); 3‐CH3C6H4 ( 3 , 7 ); 2‐OH‐3‐OCH3C6H3 ( 4 ) have been synthesized and fully characterized by FT‐IR, 1H &13C NMR spectroscopy, single crystal X‐ray crystallography and elemental analysis. The molecular geometry observed for the compounds is predominantly distorted trigonal bipyramidal, the fact which was subsequently authenticated through X‐ray analyses for ( 1 – 4 ). All the synthesized compounds have been bio‐assayed for antileishmanial (Leishmania tropica KWH23) and Jack beans urease inhibitory activity, and human Lymphocytes were used to measure the general toxicity. Of these, ( 4 ) proved to be highly effective against the target species (Leishmania tropica KWH23), while being non‐toxic towards the mammalian cells at levels below 0.74 μgmL?1, making it highly promising drug candidate. The high activities for ( 2 , 4 , and 6 ) against Jack beans Urease as compared to the reference standard demonstrate their significance in searching of therapeutic agents in future programs. The significant binding score of ( 2 & 4 ) against H. pylori in molecular docking studies further revealed their importance in future drug discovery processes. 相似文献
120.