S. Tumkevičius
1994
Citations
0
Influential Citations
9
Citations
Journal
Journal Fur Praktische Chemie-chemiker-zeitung
Abstract
The reaction of ethyl N-(6-ethoxycarbonyl-2-methyl-thiothieno[2,3-d]pyrimidin-5-yl)formimidate (1) with methyl-hydrazine, N,N′-dimethyl- and N,N′-diphenylhydrazines separately in refluxing ethanol resulted in hydrolysis of formimidate group to give ethyl 5-amino-2-methylthiothieno[2,3-d] pyrimidine-6-carboxylate (2). The reaction on 1 with methyl-hydrazine without solvent afforded ethyl 5-amino-2-(1-methyl-hydrazino)thieno[2,3-d]pyrimidine-6-carboxylate (3), which underwent hydrazone formation with p-nitrobenzaldehyde to give 4. Treatment of 1 with N,N-dimethylhydrazine afforded a mixture of 3-dimethylamino-7-methylthiothieno[2,3-d:4,5-d']dipyrimidin-4(3H)-one (5) and 2. Displacement of methylthio group in 5 with morpholine, piperidine and 4-methylpiperazine gave the corresponding 7-substituted derivatives 6a-c. The reaction of 1 with para-substituted phenylhydrazines resulted in the formation of 3-(p-substituted phenylamino)7-methylthiothieno[2,3-d:4,5-d']dipyrimidin-4 (3H)ones (7a-c).