| abstract |
The new compounds of general formula I: (CF DRAWING IN BOPI) in which: A1 is a hydrogen atom, a C1 - 4 alkyl or C4 - 8 cycloalkyl group; A2 represents C3-10 alkyl, C3-10 alkenyl, C4-8 cycloalkyl, C1-4 phenyl-alkyl, C2-4 phenyl-alkenyl; phenyl optionally substituted with one or more C1-4 alkyl, C1-4 alkoxy or hydroxy groups; naphthyl; pyridyl optionally substituted with a C1-4 alkyl group; or furfuryl; and X is a valence bond or a -CO- group; provided that in the case where X is a valence bond, A2 is other than a phenyl group, exhibit a useful effect of increasing weight gain and improving feed utilization and they can be used in breeding, in particular in chickens and lambs. The compounds of general formula I can be prepared according to methods known per se. |