Process for the manufacture of 3-hydroxy-N-alkyl-1-cycloalky1-6-alkyl-4-oxo-1,4-dihydropyridine-2-carboxamide and its related analogues
US7893269B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 2005 |
| Grant date | Feb 22, 2011 |
| Priority date | — |
| Expiry date | Jun 5, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/55
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a novel process for the preparation of 1-alkyl or 1-cycloalkyl derivatives of 3-hydroxy-4-oxo-1,4-dihydropyridine-2-carboxamide of formula (I). The process includes reacting an amine R2NH2 with a compound of formula (II) in a solution of metal hydroxide in water to give a compound of formula (III). Subsequent reaction of the compound of formula (III) with an acid chloride formation reagent in an inert solvent gives compounds of formula (I). The acid chloride formation reagent is selected from oxalyl chloride and dimethylformamide, dimethylchloromethylene-ammonium chloride and thionyl chloride and dimethylformamide. If desired, a compound of formula (I) where R5 is hydrogen may be formed when an intermediate substituent is used wherein R5 is an alcohol protective group removable by catalytic hydrogenation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.