. . "R10 represents a hydrogen atom, a halogen atom such as a chlorine atom, a C1-C4 alkyl, sulpho, carboxy, C1-C4 monohydroxyalkyl or C1-C4 hydroxyalkoxy, C1-C4 acetylaminoalkoxy, C1-C4 mesylaminoalkoxy or C1-C4 carbamoylaminoalkoxy radical;" . . .