Abstract: A process for producing butyrophenone derivatives of the formula: ##EQU1## which comprises reacting a compound of the formula: ##SPC1##With an amine of the formulaH-W(wherein Ar represents a group of either one of the formulas: ##SPC2##Z is a secondary amino group and W is the residue of an amine excluding a hydrogen atom therefrom). The said butyrophenone derivatives and their salts exhibit a variety of beneficial pharmacological activities including a central and autonomic nervous system depressing activity.

Abstract: A process for producing cyclopentane derivatives of the formula ##SPC1##Wherein R is hydrogen or a C.sub.1 to C.sub.6 alkyl group, X is a carboxyl or a carboalkoxy group, and the like; Y and Z each is a hydroxyl group, and the like; and n is an integer of from 5 to 7. The derivatives are useful as medicines. The process of this invention comprises the steps shown in the following reaction scheme: ##SPC2##Wherein R, X, Y, Z and n are as defined above, and wherein R' is lower alkyl group.

Abstract: Cyclopentane derivatives of the formula ##SPC1##Wherein R.sup.1 is a group of the formula--(CH.sub.2).sub.n --Xin which X is a carboxyl group or its homologue, a halogen atom or a hydroxyl group and n is an integer of from 1 to 7; Y.sup.1 is a formyl group of a carboxyl group or its homologue; and Z.sup.1 is a formyl group, a carboxyl group, a hydroxymethyl group, an acetyl group, an acetoxy group, or a hydroxyl group and a process for their preparation are disclosed. The process schematically comprises the Diels-Alder reaction of a compound having the formula R.sup.1 --CH=CH--Y.sup.1 with cyclopentadiene followed by oxidation of the bicycloheptene reaction product formed into a cyclopentane derivative in which Z.sup.1 is a formyl group, a hydroxymethyl group or a carboxy group.