Compounds of the formula (I) and pharmaceutically acceptable salts thereof:
wherein:
R1 is C1-6 alkyl;
R2 is hydrogen or C1-7 acyl;
R3 is C1-6 alkyl;
R4 is a group CH2R5 wherein R5 is hydrogen, C3-8 cycloalkyl or phenyl optionally substituted by one or two substituents selected from C1-6 alkyl, C1-4 alkoxy, trifluoromethyl and halogen, having useful anti-emetic activity.
式(I)化合物及其药学上可接受的盐: 其中:R1 是 C1-6 烷基;R2 是氢或 C1-7
丙烯酸基;R3 是 C1-6 烷基;R4 是基团 CH2R5,其中 R5 是氢、C3-8 环烷基或苯基,可任选被选自 C1-6 烷基、C1-4 烷氧基、三
氟甲基和卤素的一个或两个取代基取代,具有有效的止吐活性。