4 h-3, 1-benzoxazin-4-ones and related compounds

Abstract From the Canadian patent

Novel 2-amino-4H-3,1-benzoxazin-4-ones represented by the formula, and the pharmaceutically acceptable esters and salts thereof wherein R1 is hydrogen or lower alkyl; R2 and R3 are each independently hydrogen halo, lower alkyl, hydroxy, lower alkoxy lower, thioalkyl, -NO2, -N(R')2, -NR'COR' -NHCON(R')2 or -NHCOOR', with the proviso that at least one of R1 R2 and, R3 is not hydrogen when X is NHR or NR'COR''; and X is a radical chosen from the group consisting of: -AN(R')2 and -AOR', (A) (B) (C) (D), in which: R is lower alkyl, lower alkenyl, lower alkynyl optionally substituted lower cycloalkyl or optionally substituted phenyl lower alkyl; each R' is independently hydrogen or lower alkyl …