摘要 |
Compounds of the formula <CHEM> wherein R is hydrogen or a lower alkyl group or COR<1><5> R<1>, R<2>, R<1><1> and R<1><2>, are hydrogen or a lower alkyl group, R<3>, R<4>, R<5> and R<6> are hydrogen, hydroxy, halogen, a lower alkyl group, a lower alkoxy group or a mono- or di-lower alkyl amino group, NH2 or NR<1><3>COR<1><4>, R<7>, R<8>, R<9> and R<1><0> are hydrogen, hydroxy, a lower alkyl group, a lower alkoxy group, a mono- or di-lower alkylamino group, or NH<1><3>COR<1><4> wherein R<1><3>, R<1><4> and R<1><5> are hydrogen or a lower alkyl group, enantiomers and salts thereof, with the proviso that when R is COR<1><5> then at least one of R<3> to R<1><0> are hydroxy or a mono or di-lower alkylamino group, are useful as antioxidants, within the medical and non-medical field. Many of the compounds of formula IA and IB are new and various methods for preparing them are described. |