2,4,7-substituted 5-hydroxy benzopyrans and esters
US3947462A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1974 |
| Grant date | Mar 30, 1976 |
| Priority date | — |
| Expiry date | May 22, 1994 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C37/055
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
2,4,7-Substituted 5-hydroxy benzopyrans and dihydrobenzopyrans and their esters represented by the formulae ##SPC1## Wherein each R.sub.1 is loweralkyl, and R.sub.2 is hydrogen, loweralkanoyl or ##SPC2## With Y being a straight or branched chain alkylene group having from 1-8 carbon atoms; a is an integer from 1-4; b is an integer from 1-4; X is CH.sub.2, O, S, or NR.sub.5 with R.sub.5 being hydrogen or loweralkyl, with the limitation that when X is O, S, or NR.sub.5, the sum of a and b is 3 or 4 and R.sub.4 is hydrogen or loweralkyl; and R.sub.3 is ##SPC3## With Y' being a straight or branched chain alkylene group having from 1-10 carbon atoms; and each R.sub.7, R.sub.8 and R.sub.9 are the same or different members of the group consisting of hydrogen, halo, trifluoromethyl or loweralkyl and the pharmaceutically acceptable salts thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.