排序方式: 共有22条查询结果,搜索用时 15 毫秒
1.
2.
3.
Obydennov Dmitrii L. Simbirtseva Alena E. Sosnovskikh Vyacheslav Y. 《Research on Chemical Intermediates》2022,48(5):2155-2179
Research on Chemical Intermediates - Synthesis of 2-cyano-6-styryl-4-pyrones has been developed on the basis of 6-metylcomanic acid via modifications of the methyl and carboxyl groups. Reactions of... 相似文献
4.
The reaction of 1-aryl-2-(dimethylaminomethylene)butane-1,3-diones with diethyl oxalate in the presence of sodium hydride in THF gave ethyl 5-aroyl-4-oxo-4H-pyran-2-carboxylates, from which 4-oxo-6-aryl-4H-pyran-2-carboxylic acids (6-arylcomanic acids) were obtained in high yields via acid-catalyzed deformylative rearrangement. 5-Aroyl-4-oxo-4H-pyran-2-carboxylic acids (5-aroylcomanic acids) were prepared via а ring-opening/ring-closure sequence by the reaction of 5-aroyl-2-carbethoxy-4-pyrones with piperidine and subsequent basic hydrolysis and acidification. 相似文献
5.
6.
7.
Russian Chemical Bulletin - 相似文献
8.
6-Tri- and 6-difluoromethylcomanic acids and their ethyl esters reacted with aminoguanidine, predominantly giving 5-RF-pyrazolo[1,5-c]pyrimidines, whereas the reaction of the openchain synthetic equivalents, i.e., ethyl 7,7,7-trifluoro- and 7,7-difluoro-2,4,6-trioxoheptanoates, with this polynucleophile allowed us to obtain regioselectively 2-RF-pyrazolo[1,5-c]pyrimidines. 相似文献
9.
A simple and efficient method for the synthesis of ethyl 5-alkanoyl- and 5-aroyl-4-pyrone-2-carboxylates was developed, which is based on the condensation of 1-R-2-(dimethyl-aminomethylidene)butane-1,3-diones, obtained from 1,3-diketones and dimethylformamide dimethyl acetal, with diethyl oxalate in the presence of NaH in THF. Ethyl 5-acyl-4-pyrone-2-carboxylates were used in the synthesis of 6-R- and 5-RCO-comanic acids. 相似文献
10.
Obydennov K. L. Kosterina M. F. Klimareva E. L. Bakulev V. A. Morzherin Yu. Yu. 《Russian Chemical Bulletin》2011,60(5):1016-1018
Reactions of malonothioamides with acetylenedicarboxylates proceed as an addition of the sulfur atom at the triple bond with
subsequent intramolecular reaction between the ester group and the nitrogen atom, that leads to substituted thiazolidines.
Unsubstituted malonodithioamide and N-cyclohexylmalonodithioamide give adducts involving both thioamide fragments, whereas N,N′-bis(4-methoxyphenyl)malonodithioamide forms the 1: 1 adducts. 相似文献