| abstract |
(57) [Summary] Formula (I) wherein A is a hydrogen atom, hydroxyl, C 1-6 hydroxyalkyl group, thiol, C 1-6 alkylsulfanyl group, amino group, C 1-6 alkylamino group, di (C 1-6 Alkyl) amino, C 1-6 alkylhydroxylamine, C 1-6 alkoxy, hydroxylamine, C 1-6 N, O-dialkylhydroxylamine, azide or halogen such as fluorine, chlorine or bromine B represents a hydrogen atom, a linear or branched C 1-6 alkyl group, a C 2-6 alkenyl group, a C 1-6 fluoroalkyl group, a C 1-2 perfluoroalkyl group, a C 1 -6 represents an alkoxy group, a phenyl group or an oxo group, and X represents an oxygen or sulfur atom]. The invention is useful in therapy. |