Phenylcyclobutylamide derivatives and their optical isomers, the preparingprocesses and the uses thereof, which includes the compounds of formula (I),their pure stereoisomers and their pharmaceutically acceptable salts. Informula(I), R is H, formacyl, acetyl, haloacetyl, benzoyl, benzyloxy carbonyl (Cbz),t-butoxy carbonyl (Boc), or 9-fluorenyl methoxyl carbonyl (Fmoc). The presentnovel compounds have pharmaceutical activity and are prepared bycondensation reaction of racemic, levo- or dextro- demethyl Sibutramine andracemic or D/L isoleucine under a mild condition. It is demonstrated that thepresent compounds have effect of losing weight to obese mode rats in differentlevel and the effect is better than Sibutramine by the animal experiments. Sothemedicaments prepared by the present compounds or the medicaments preparedby the compositions of the present compounds and other pharmaceutical activitycompounds may be used for treating obesity.(see formula I)
