REACTIONS OF 3,4-DICHLORO-N-R-MALEIMIDES WITH SUBSTITUTED 2-THIOURACILS

Authors

  • Ю. М. Воловенко Taras Shevchenko Kiev National University, Kiev 01033
  • Г. Г. Дубинина Taras Shevchenko Kiev National University, Kiev 01033
  • А. Н. Чернега Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Kiev 02094

Keywords:

7-R-2-R2 -3-R1 -7,8-dihydro-4H,6H-pyrrolo[3',4':4.5][1,3]thiazolo[3,2-a]pyrimidine-4,6,8-triones, N2 -R-6-R1 -5-oxo-5H[1,3]thiazolo[3,2-a]pyrimidine-2-carboxamide, nucleophilic substitution in 3,4-dichloro-N-R-maleimides

Abstract

Reactions of 3,4-dichloro-N-R-maleimides with substituted thiouracils at 40°C gave a 1:1 mixture of isomers of pyrrolothiazolopyrimidinetriones. Under conditions of thermodynamic control (100°C, 5 h) only pyrrolo[3',4':4,5]thiazolo[3,2-a]pyrimidine-4,6,8-triones were formed, hydrolysis of which followed by decarboxylation gave 5-oxo-5H-thiazolo[3,2-a]pyrimidine-2-carboxamide. The structure of N2-phenyl-6-methyl-5-oxo-5H-thiazolo[3,2-a]pyrimidine-2-carboxamide was confirmed by X-ray crystallography. Analogous cyclization of 3,4-dichloro-N-R-maleimides with 2-thioxoquinazol-4-one also gave a mixture of two isomers which were successfully separated by fractional crystallization.

How to Cite
Volovenko, Yu. M.; Dubnina, G. G.; Chernega, A. N. Chem. Heterocycl. Compd. 2004, 40, 94. [Khim. Geterotsikl. Soedin. 2004, 100.]

For this article in the English edition, see DOI 10.1023/B:COHC.0000023775.37226.f1

Published

2004-01-25

Issue

Section

Original Papers