| 摘要 |
Compounds of the formula <IMAGE> I wherein R1 is hydrogen, lower alkyl or acyl; R2 and R3 independently are lower alkyl, aralkyl or alkenyl or R2 and R3 together form a ring of 5 to 8 carbon atoms; R4 is phenyl, substituted phenyl, cyclohexyl, substituted cyclohexyl, cyclopentyl, substituted cyclopentyl, cycloheptyl, or substituted cycloheptyl; R5 is hydrogen or lower alkyl; R6 is hydrogen, lower alkyl or acyl; and pharmaceutically acceptable acid addition salts thereof are described. The compounds of formula I and pharmaceutically acceptable acid addition salts thereof are anti-emetic agents which lack central nervous system side effects. |
