Patent ID: 6177409
Filing Date: 2001-01-23
Classification: C07D,C07H

Abstract:
A process for regiospecific synthesis of new 3-hydroxypyridine-4(1H)-one derivatives of general formula: ##STR22##in which R represents an alkyl or alkylene or halo-alkyl or halo-alkylene radical, the halogens being chosen from among chloride and fluoride, linear or branched, having from 1 to 4 carbon atoms and having hetero-atoms or not, and Sub represents an itol, either cyclic or not, protected or not, starting from a 2-R-3-hydroxy pyran-4-one derivative and an amino itol, wherein said process comprisesa first step (step a) of protection of the 3-hydroxy group of the pyranone derivative;a second step (step b) of substitution of the intracyclic oxygen atom of the pyranone by the nitrogen atom of the amine function of the amino itol, to obtain the 2-R-3-hydroxypyridine-4(1H)-one derived from the itol, in which the protected pyranone obtained in step (a) is reached with the amino itol, in the presence of a strong base;a third step (step c) of de-protection of the 3-OH group of the pyridinone cycle.