113778-34-0Relevant articles and documents
Transesterification of ketoesters using Amberlyst-15
Chavan,Tripura Subbarao,Dantale,Sivappa
, p. 289 - 294 (2001)
A facile one-to-one transesterification of ketoesters by Amberlyst-15 is described.
Ag-Cu nanoparticles as efficient catalysts for transesterification of β-keto esters under acid/base-free conditions
Yue, Hongmei,Yu, Hao,Liu, Sheng,Xu, Chunli
, p. 19041 - 19051 (2016/03/01)
Transesterification of β-keto esters and alcohols are traditionally catalyzed by acid or basic catalysts. However, these traditional catalysts do not always meet the requirements of modern synthetic chemistry which need to be highly efficient, selective, and environmentally friendly. In this work, Ag-Cu metal sites were first introduced as transesterification catalysts. The effect of the support, Ag:Cu molar ratio, and reaction conditions were investigated. The Ag-Cu metal sites were proved to be active in the β-ketoester transesterification with various alcohols, having yields comparable to the conventional acid- or base-catalysts.
Lipophilic 4-imidazoly-1,4-dihydropyridines: Synthesis, calcium channel antagonist activity and protection against pentylenetetrazole-induced seizure
Navidpour, Latifeh,Shafaroodi, Hamed,Miri, Ramin,Dehpour, Ahmad Reza,Shafiee, Abbas
, p. 261 - 269 (2007/10/03)
A group of alkyl, cycloalkyl and aryl ester analogs of nifedipine, in which the o-nitrophenyl group at position 4 is replaced by a 2-phenyl-4(5)-imidazolyl substituent, were synthesized and evaluated as calcium channel antagonist using the high K+ contraction of guinea-pig ileal longitudinal smooth muscle, and the activity of 5a-d, 8b and 8f against pentylenetetrazole (PTZ)-induced seizure was assessed. The results for symmetrical esters showed that lengthening of the methylene chain in C3 and C5 ester substituents increased activity. When increasing of the length is accompanied by increasing the hindrance, the activity decreased. In contrast to symmetrical derivatives, comparison of the activities of asymmetrical esters showed that increasing the length of the methylene chain was accompanied by a decrease in their activity. The results demonstrate that 8a was more active, and 5c and 8f were similar in effect to that of the reference drug nifedipine. The time-course of anticonvulsant effect on PTZ-induced seizure threshold of said compounds was assessed and showed that increasing the lipophilicity decreases the time needed for maximum effect. Mice treated with intraperitoneal injection of 25 mg/kg of these derivatives all exhibited increase seizure threshold as compared with control.