RECYCLIZATION OF CONDENSED CARBETHOXYPYRIMIDINES ACCOMPANIED BY SUBSTITUTION OF A CARBON ATOM INTO THE HETEROCYCLE

Authors

  • Г. Г. Данагулян Institute of Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Yerevan 375094
  • А. Д. Мкртчян Institute of Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Yerevan 375094
  • Г. А. Паносян Molecular Structure Research Center, National Academy of Sciences of the Republic of Armenia, Yerevan 375014

DOI:

https://doi.org/10.1007/8327

Keywords:

pyrazolo[1, 5-a]pyrimidine, 1, 2, 4-triazolo[1, rearrangement, recyclization

Abstract

Condensation in ethanol of ethyl ethoxymethyleneacetoacetate with systems containing an amidine fragment (substituted 3-aminopyrazoles and 3-amino-1,2,4-triazole) gave 6-carbethoxy-7-methylpyrazolo[1,5-a]pyrimidines. Addition of base  to solutions of the obtained bicyclic carbethoxy derivatives in the course of several minutes caused rearrangement to 6-acetyl-7-hydroxypyrazolo-[1,5-a]pyrimidine and 6-acetyl-7-hydroxy-1,2,4-triazolo[1,5-a]pyrimidine respectively. A more prolonged refluxing in 15% aqueous alcohol solution of base caused 6-carbethoxy-7-methyl-2-phenylpyrazolo[1,5-a]pyrimidine and 6-acetyl-7-hydroxy-2-phenylpyrazolo[1,5-a]pyrimidine to recyclize to 7-methylpyrazolo[1,5-a]pyrimidine.

How to Cite
Danagulyan, G. G.; Mkrtchyan, A. D.; Panosyan, G. A.  Chem. Heterocycl. Compd. 2005, 41, 485. [Khim. Geterotsikl. Soedin. 2005, 569.]

For this article in the English edition, see DOI 10.1007/s10593-005-0176-6


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Published

2023-11-17

Issue

No. 4 (2005)

Section

Original Papers