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991.
Y. Z. Song F. X. Zhu Y. Song J. F. Zhou X. Z. Chu F. Y. Wu A. F. Zhu C. M. Wei J. Song X. Li J. Xu 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(1):80-83
A sensor based on gold nanoparticle on the surface of L-cysteine modified gold electrode is prepared. Electrochemical behavior of dopamine hydrochloride is investigated. The linear relation between peak current of dopamine hydrochloride and scan speed in the range of 10 to 1000 mV s?1 indicates that a diffusion-adsorption controls the process. The linearity range is 1.05 × 10?5–7.38 × 10?4 M with detection limit of 1.05 × 10?6 M. The recoveries were in the range from 99.8 to 101.5% with relative standard deviations of 1.3 ~ 2.3% (n = 6). The modified electrode under ambient conditions over a period of 2 weeks has an excellent repeatability and reproducibility. 相似文献
992.
Yang‐Heon Song 《合成通讯》2013,43(5):631-635
Selective oxidation of benzylic, allylic, and saturated secondary alcohols to the corresponding aldehydes or ketones by benzyldimethyltelluronium dichromate is described. 相似文献
993.
Dialkyl, diaryl, and aryl alkyl sulfoxides can be rapidly converted to the corresponding sulfides with a WCl6/In system in excellent yields under mild conditions. 相似文献
994.
Zaesung No Shi Yong Ryu Seong-Kie Kim Jong Woong Ahn Bok Ju Song Keun Jae Kim 《合成通讯》2013,43(5):887-892
Thermal or base-promoted conversion of 5′-O-TBDMS-3′-O-(1H-imidazole-1-thiocarbonyl)thymidine (1) afforded 5′-O-TBDMS-2,3′-anhydro-thymidine (2), a pivotal intermediate for the transformation of the 3′-hydroxy group of 2′-deoxyribonucleosides, in high yield. 相似文献
995.
Abstract Task‐specific ionic liquids possessing two Brönsted acid sites with –COOH, HSO? 4, or H2PO? 4 groups have been designed, synthesized, and characterized. Under mild conditions and without any additional organic solvent, the esterification of isopropanol by chloroacetic acid could be carried out in these new task‐specific ionic liquids. In comparison with most of acidic ionic liquids in current use, these ionic liquids are halogen free and more environmentally benign as media and catalysts. 相似文献
996.
A novel and environmentally benign synthetic method for ureas through hydrogen peroxide–promoted desulfurization of thioureas at room tepemperature via grinding is reported. As compared with the traditional method, this one is manipulatively simple and the oxidant is low cost, highly active, and environmentally friendly. 相似文献
997.
A series of 5‐benzylidenerhodamine derivatives were synthesized by the cross‐aldol condensation of an aromatic aldehyde with rhodamine or rhodamine acetic acid in sodium acetate/acetic acid under microwave irradiation. The reaction was completed in 8–20 min with 63–94% yields and was environmentally benign with easy workup. 相似文献
998.
Biao Yang Guang-Ying Chen Xiao-Ping Song Liu-Qing Yang Chang-Ri Han Xiang-Yang Wu Cai-Juan Zheng Xu Ran Ri-Feng Tang 《Tetrahedron letters》2013
Phytochemical study of the twigs of Trigonostemon xyphophylloides led to the isolation of six new heterodimers, trigoxyphins O (1) and R–T (4–6) comprising of two different degraded diterpenoids, and trigoxyphins P (2) and Q (3) comprising a degraded diterpenoid and a phenylpropanoid, together with a known homodimer, neoboutomannin (7). The structures and relative configurations were elucidated on the basis of extensive spectroscopic analysis, including 1D and 2D NMR experiments. Compounds 1–6 were evaluated for their cytotoxicity against four human tumour cell lines by MTT assay. 相似文献
999.
1000.