Preparing amidines derived from 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid
US6653472B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2002 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | May 11, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D311/66
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
New intermediates of the formula (II)B described below for the synthesis of amidine derivatives of (−)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid, such as for example (S)-N-{4-[4-[(3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-yl)-carbonyl]-1-piperazinyl]phenyl}-2-thiophenecarboximidamide wherein A′ is X is —Z1—CO;&rgr; is a bond or a heterocycle selected from the group consisting of piperidine, piperazine, homopiperazine, 2-methylpiperazine, 2,5-dimethyl-piperazine and 4-aminopiperidine;Y is —Z2— or —NR3—Z2,R3 is hydrogen, alkyl of 1 to 6 carbon atoms or —COR4,R4 is alkyl of 1 to 6 carbon atoms;Z1 and Z2 independently are a single bond or alkylene of 1 to 6 carbon atoms;and R6 is hydrogen or OH.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.