Synthesis of thiazole derivatives
US5856501A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 1997 |
| Grant date | Jan 5, 1999 |
| Priority date | — |
| Expiry date | Dec 11, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D277/48
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
N-4-(cyanoethylthiomethyl)-2-thiazolyl!guanidine--a key intermediate for preparing the pharmaceutical, famotidine--is produced by mixing in a liquid medium formed from a chemically indifferent organic solvent and water, and under an inert atmosphere, (i) a 2-guanidino-4-halomethylthiazole or a hydrohalide complex thereof, (ii) an S-(2-cyanoethyl)isothiourea or a hydrohalide complex thereof, and (iii) a strong alkali metal base. In lieu of (ii), an alkali metal salt of 2-cyanoethyl-1-thiol can be used, and in such case use of (iii) is optional, but preferable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.