Process for preparing 4-arylamino-benzopyran and related compounds
US5629429A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | May 13, 1997 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D493/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method of preparing compounds of the formula ##STR1## and pharmaceutically acceptable salts thereof which comprises converting a compound of the formula ##STR2## where the R.sup.2 substituent contains a hydrogen atom which is more acidic than the starred (*) hydrogen atom in formula II, to the corresponding dianion of formula ##STR3## where M is a counterion preferably lithium or magnesium, using two equivalents of a base in an inert solvent such as tetrahydrofuran; then reacting compounds of formula IIA with an epoxide of formula ##STR4## to produce the compounds of formula I.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.