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1.
2.
Ellis MJ Antonyuk SV Strange RW Sawers G Eady RR Hasnain SS 《Inorganic chemistry》2004,43(24):7591-7593
Copper nitrite reductases contain both an electron-transfer type 1 Cu site and a catalytic type 2 Cu site. We have mutated one of the type 2 copper ligating histidines to observe the effect on catalytic turnover. This mutation has created a unique site where Cu is ligated by 2 His Nepsilon2 atoms alone. 相似文献
3.
The synthesis of N-(dimethoxy and 3, 5-diacetoxybenzoyl) -L- amino acid hydrazides, and their reactions with some aldehydes and ketones are described. 相似文献
4.
Ajaj Rahaf Shubyar Nasser Alashban Yazeed El-Sayed Samar Salah Tamar Al Yafei Mohammed A. Salem 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):923-928
Journal of Radioanalytical and Nuclear Chemistry - Groundwater is the most valuable resource in arid regions, such as UAE. Estimations of natural radionuclide concentrations are important to... 相似文献
5.
Lamya H. Al-Wahaibi Ahmed A. B. Mohamed Samar S. Tawfik Hanan M. Hassan Ali A. El-Emam 《Molecules (Basel, Switzerland)》2021,26(8)
The reaction of 5-(3,4-dimethoxyphenyl)-1,3,4-oxadiazole-2(3H)-thione 3 with formaldehyde solution and primary aromatic amines or 1-substituted piperazines, in ethanol at room temperature yielded the corresponding N-Mannich bases 3-arylaminomethyl-5-(3,4-dimethoxyphenyl)-1,3,4-oxadiazole-2(3H)-thiones 4a–l or 3-[(4-substituted piperazin-1-yl)methyl]-5-(3,4-dimethoxyphenyl)-1,3,4-oxadiazole-2(3H)-thiones 5a–d, respectively. The in vitro inhibitory activity of compounds 4a–l and 5a–d was assessed against pathogenic Gram-positive, Gram-negative bacteria, and the yeast-like pathogenic fungus Candida albicans. The piperazinomethyl derivatives 5c and 5d displayed broad-spectrum antibacterial activities the minimal inhibitory concentration (MIC) 0.5–8 μg/mL) and compounds 4j, 4l, 5a, and 5b showed potent activity against the tested Gram-positive bacteria. In addition, the anti-proliferative activity of the compounds was evaluated against prostate cancer (PC3), human colorectal cancer (HCT-116), human hepatocellular carcinoma (HePG-2), human epithelioid carcinoma (HeLa), and human breast cancer (MCF7) cell lines. The optimum anti-proliferative activity was attained by compounds 4l, 5a, 5c, and 5d. 相似文献
6.
Fayçel Jemmezi Samar Chtiba Jameleddine Khiari 《Journal of heterocyclic chemistry》2013,50(2):206-208
The symmetrical vinamidinium salts were allowed to react with malononitrile in refluxing ethanol in the presence of ammonium acetate for 12 h to afford the 2‐amino‐5‐aryl or formylpyridine‐3‐carbonitriles. 相似文献
7.
A series of new methyl N-(dimedioxy / 3,5-diacetoxybenzoyl)-L-amino acid esters have been synthesized by two methods. 相似文献
8.
[MoVIO2(S2C2(CN)2)2]2− (┘1) and [MoIVO(S2C2(CN)2)2]2− (2) mimick oxidoreductase enzymatic activities of sulphite oxidase with biological electron donor, SO
3
2−
, andin vitro electron acceptor, [Fe(CN)6]3−, demonstrating proton coupled electron transfer reaction in water and inhibition of the oxidation of (2) in the presence of KCN. The sulphite exidizing system is characterized by substrate saturation kinetics indicating the biological
significance of the reactions 相似文献
9.
Bhahwal A. Shah Vijay K. Sethi Samar S. Andotra Ghulam N. Qazi 《Tetrahedron letters》2007,48(6):955-960
The Baylis-Hillman reaction of a sesquiterpene lactone parthenin with various aldehydes gave unexpected products containing a 1,3-dioxolane moiety. Both small aliphatic and aromatic aldehydes produced 1,3-dioxolanes, whereas higher aliphatic aldehydes produced normal Baylis-Hillman products. 相似文献
10.
[Reaction: see text]. A highly efficient synthetic method of carotenoid compounds has been developed on the basis of the sulfone coupling and double-elimination strategy. This method highlighted the sulfone-mediated coupling with the novel C(10) dialdehyde, 2,7-dimethyl-4-octenedial, which was easily prepared and efficiently utilized in the synthesis of the conjugated polyene chains. 相似文献