| abstract |
The enantiomer enriched compounds of formula I ** (Formula) ** including the optical isomers thereof and mixtures of such isomers, wherein R 1 is hydrogen, alkyl, cycloalkyl or optionally substituted aryl, R 2 and R 3 are each independently hydrogen or alkyl, R4 is alkyl, alkenyl or alkynyl, R5, R6, R7 and R8 are each independently hydrogen or alkyl, R9 is hydrogen, optionally substituted alkyl, optionally substituted alkenyl or optionally substituted alkynyl, R10 is optionally substituted aryl, or optionally substituted heteroaryl, and Z is optionally substituted aryloxy, optionally substituted alkoxy, optionally substituted alkenyloxy or optionally substituted alkynyloxy. |