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41.
Alan R. Katritzky Malgorzata Drewniak-Deyrup Xiangfu Lan Frederic Brunner 《Journal of heterocyclic chemistry》1989,26(3):829-836
Indole, carbazole, pyrrole, imidazole, benzimidazole, 2-methyl- and 2-phenylbenzimidazole, and 1, 2, 4-triazole have each been converted into their N-(benzotriazol-1-ylmethyl) derivatives. The pyrrole, indole, and carbazole adducts undergo smooth lithiation at the inter-ring methylene group and subsequent reaction there with electrophiles. For the imidazole, benzimidazole, and triazole systems, lithiations at other molecular positions competed. 相似文献
42.
Wang Li Duan Liying Wang Enbo Xiao Dongrong Li Yangguang Lan Yang Xu Lin Hu Changwen 《Transition Metal Chemistry》2004,29(2):212-215
The novel complex, Co(H2O)5[Co(2,6-pydc)2] (1) has been prepared in aqueous solution and characterized by single-crystal X-ray diffraction, elemental analyses and i.r. spectra. X-ray structural analysis revealed that three novel compounds each possess both – stacking and hydrogen-bonding interaction three-dimensional (3-D) networks. 相似文献
43.
阿斯美胶囊中四种组分的高效液相色谱分析 总被引:2,自引:0,他引:2
建立了反相高效液相色谱法测定阿斯美胶囊中氨茶碱、盐酸甲氧非那明、马来酸氯苯那敏及那可汀四种组分的含量。色谱柱为SpherisorbC8,5μm,200cm×40mmID,流动相为体积分数05%的三乙胺溶液(磷酸调节pH55)+乙腈+甲醇(550+368+82),检测波长为264nm,线性范围分别为:氨茶碱3125~250mg/L,γ=09996,盐酸甲氧非那明15625~1250mg/L,γ=10000,马来酸氯苯那敏25~200mg/L,γ=09999,那可汀875~700mg/L,γ=09999;回收率(n=3)分别为1012%,1008%,999%,995%;精密度:日内平均RSD(n=6)分别为07%,04%,04%,06%;日间平均RSD(n=3)分别为10%,10%,11%,12%。 相似文献
44.
45.
Kinetic study on the cleavage of N‐phenylphthalimide (NPhPT) in the presence of 0.05 M NH2NH2 and mixed H2O‐CH3CN solvents reveals the occurrence of reaction scheme where A, B, C, C1, An, E, and F represent NPhPT, o‐CO?2C6H4CONHC6H5, o‐CONHNH2C6H4‐ CONHC6H5, N‐aminophthalimide, aniline, o‐CO?2C6H4CONHNH2, and o‐CONHNH2C6H4‐CONHNH2, respectively. But, in the presence of either nonbuffered ?0.20 M NH2NH2 hydrazine buffer of pH ~7.30–8.26 with total buffer concentration ([Buf]T) of >0.02 M, further conversion of F to 2,3‐dihydrophthalazine‐1,4‐dione (DHPD) has been detected depending upon the length of the reaction time (t), the values of [Buf]T, and pH. It has been shown that the rate of conversion of C1 to F is much faster than that of C to C1 which is much faster than that of F to DHPD. The reaction step A → C involves general base (GB) catalysis, while step C → C1 seems to involve specific base–general acid (GA) and GB‐GB catalysis. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 37: 147–161, 2005 相似文献
46.
N-(α-Benzotriazolylalkyl)arylacetamides, readily available from an arylacetamide, an aldehyde and benzotriazole, undergo intramolecular cyclization under acidic conditions to give 1-aryl-1,4-dihydro-3(2H)-isoquinolinones in good to excellent yields. Similarly, 2-(benzotriazol-1-yl)-2-(o-hydroxyphenyl)ethanols, obtained by lithiation of 2-(benzotriazol-1-ylmethyl)phenols followed by quenching with aldehydes or ketones, eliminate a molecule of water and a molecule of benzotriazole yielding 2-substituted and 2,3-disubstituted benzofurans. 相似文献
47.
Bai JZ Bardon O Blum I Breakstone A Burnett T Chen GP Chen HF Chen J Chen SJ Chen SM Chen Y Chen YB Chen YQ Cheng BS Cowan RF Cui HC Cui XZ Ding HL Du ZZ Dunwoodie W Fan XL Fang J Fero M Gao CS Gao ML Gao SQ Gao WX Gratton P Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y Harris FA Hatanaka M He J He KR He M Hitlin DG Hu GY Hu HB Hu T Hu XQ Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jin Y Jones L Kang SH Kelsey MH Kim BK Lai YF Lan HB Lang PF Lankford A Li F Li J Li PQ Li Q Li RB 《Physical review D: Particles and fields》1995,52(7):3781-3784
48.
F. M. Lanças M. A. Barbirato N. R. Antoniosi filho 《Journal of Radioanalytical and Nuclear Chemistry》1995,189(2):319-323
Three nitrogenated fungicides (Bayfidan, Bayleton and Baycor) were irradiated with -rays from a60Co source with the products being analyzed by high resolution gas chromatography (HRGC). Within the dose range studied (5 to 640 kGy), all three compounds were found to be stable. 相似文献
49.
50.
Aihua Zhang Kun Liu Lan Li Siyu Ma Zonghe Li 《International journal of quantum chemistry》2005,104(3):373-378
The ring‐closing reaction of 5′‐adenosine monophosphate (5′‐AMP) to generate cyclic 3′, 5′‐adenosine monophosphate (cAMP) and H2O was theoretically investigated at the B3LYP/6‐31G**level. It was found that the ring‐closing reaction of 5′‐AMP may proceed in a synchronous way or in a stepwise way. For the latter, the reaction is a multichannel elimination reaction including inner H transfer. The potential energy surface of Path 3 is lowest in all the ring‐closing reaction paths. In addition, H shuttling reaction with the participation of a water molecule to act as a shuttle were also studied at the same level. The calculations indicate that the participation of a water molecule facilitates hydrogen transfer reaction. Our present calculations rationalized all the possible reaction channels. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献