Patent · US Expired

Intermediates useful in the preparation of 3,4-dihydro-4-oxothieno[2,3-d]pyrimidine-2-carboxylates and process for preparing same

US4701528A · kind A · utility

2Cited by
2References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1985
Grant dateOct 20, 1987
Priority date
Expiry dateDec 23, 2005

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D495/04
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

There are disclosed compounds of Formulas I and II: ##STR1## wherein R.sup.1 and R.sup.2 may be hydrogen, lower alkyl having from 1 to 8 carbon atoms, lower alkenyl having from 3 to 6 carbon atoms, lower alkoxy having from 1 to 6 carbon atoms, hydroxy, nitro, amino, halo including chlorine, bromine, iodine, and fluorine, phenyl, alkanoyl having from 2 to 6 carbon atoms or they are bonded to one another to form a cycloalkene ring fused to the thiophene ring and having a total of from 5 to 7 annular ring carbon atoms, and R.sup.3 is an aliphatic or an aromatic group such as lower alkyl, e.g., methyl or ethyl. Such compounds are useful as intermediates in the production of tiprinast and related compounds. There is also disclosed a process for the regioselective synthesis of a compound of Formula I wherein R.sup.1 is CH.sub.3 and R.sup.2 is (CH.sub.3).sub.2 CHCH.sub.2 which comprises reacting a mixture of compounds of the following formulas: ##STR2## and ##STR3## with trichloroacetonitrile under acidic conditions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.