SYNTHESIS OF SOME NEW PHENYL 2H-1-BENZOPYRAN-2-ONES: NOVEL STRUCTURE FOR NIVEGIN

Article abstract of DOI:10.1016/S0040-4020(01)80049-1

The constitution of nivegin, occurring in Echinops niveus has been revised by synthesising 5,7-dihydroxy-4-(4-hydroxyphenyl)-2H-1-benzopyran-2-one(1), 5,7-dihydroxy-3-(4-hydroxyphenyl)-2H-1-benzopyran-2-one(2) and their derivatives 3-6.It has been assigned a novel structure having the phenyl substituent in the benzenoid ring of the coumarin nucleus - 4,5-dihydroxy-7-(4-hydroxyphenyl)-2H-1-benzopyran-2-one(11).