| abstract |
Derivatives of formula (I), wherein R1? represents H or C1?-C4? alkyl; X represents an oxygen atom, a methylene group or a -CH=CH- group; n has a value of 1 or 2 when X is an oxygen atom or a methylene group, and a value of 0 or 1 when X is a -CH=CH- group; R3? represents a C1?-C4? alkyl group, C3?-C7? cycloalkyl, phenyl, benzyl, CHF2?, CF3?, or CF3?CF2?; R2? and R'2? each represent independently a hydrogen atom or a C1?-C4? alkyl group, a C4?-C7? cycloalkyl group, a phenyl group or a benzyl group; R'2? and R3? can further form a -(CH2?)3?- or -(CH2?)4?- chain; and R4? and R'4? each independently represent a C1?-C4? alkyl group or together form either a -(CH2?)2?- or -(CH2?)3?- chain, or a -(CH2?)2?- or -(CH2?)3?- chain substituted by one or two C1?-C4? alkyl groups, or a -(CH2?)2?- chain substituted by one or two -CH2?-NH2? groups or by one or two -CH2?-NH2? groups N-substituted by one or two C1?-C4? alkyl groups, which are useful as medicines. |