ES295441A1 - Procedure for the obtaining of new 5,6,7,8-tetrahydro-pyrid (4,3-d) pyrimidine (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Procedure for obtaining new 5,6,7,8-tetrahydropyrido [4,3-d] pyrimidines of the formula ** (See formula) ** where R represents a hydrogen atom, an alkyl, aryl or aralkyl radical, R 1 a hydrogen atom, an alkyl radical substituted by an amino radical or an alkoxy radical, a cycloalkyl, aryl or aralkyl radical, and R 2 may be a hydrogen atom, an alkyl moiety, an aryl or aralkyl moiety, a monosubstituted or disubstituted free amino group, the nitrogen atom of which may also be a member of a saturated heterocyclic ring optionally containing another heteroatom, or a free mercapto group or substituted by an alkyl or aralkyl radical, optionally substituted by halogen, and its acid addition salts, characterized by reacting an ester of piperidonecarboxylic acid of the formula ** (See formula) ** where R and R1 have the indicated meaning and Alk represents a lower alkyl residue, with an amidine of the formula ** (See formula) ** wherein R2 has the meaning indicated above, preferably in the presence of an alkaline condensation agent and conveniently in the presence of a solvent, and, if a compound is formed in which R2 represents a free or substituted mercapto group, it is optionally converted subsequently to ammonia, with a primary or secondary amine, preferably with an excess of said amine, and preferably at temperatures comprised between 20 and 180 [deg.] in the basic residues indicated above under R.sub.2, and the compounds thus obtained are optionally transformed into their acid addition salts with an inorganic or organic acid. (Machine-translation by Google Translate, not legally binding)