Abstract: Described are caffeic acid derivatives represented by the following formula: ##STR1## wherein either one of R.sup.1 and R.sup.2 is a hydrogen atom, a C.sub.1 -C.sub.6 alkyl group, a group --CO.sub.2 R.sup.4, or a group --CONR.sup.5 R.sup.6, R.sup.4, R.sup.5 and R.sup.6 being either a hydrogen atom or a particular group, and the other is the group --CO.sub.2 R.sup.4 or the group --CONR.sup.5 R.sup.6, or R.sup.1 and R.sup.2 are coupled together to represent a 5-membered ring so formed, Y represents a particular group or atom, X represents a substituted or unsubstituted C.sub.6 -C.sub.10 aryl, C.sub.7 -C.sub.12 aralkyl, heterocyclic or heterocyclic ring-alkyl group, m and n stand for particular integers, and R.sup.3 represents a hydrogen atom, a hydroxyl group, a group --OCO.sub.2 R.sup.7, R.sup.7 being a hydrogen atom or a particular group, or a group --OCONR.sup.8 R.sup.9, R.sup.8 representing a C.sub.1 -C.sub.6 alkyl group and R.sup.9 representing a hydrogen atom or a C.sub.1 -C.sub.

Abstract: Described are caffeic acid derivatives represented by the following formula: ##STR1## wherein either one of R.sup.1 and R.sup.2 is a hydrogen atom, a C.sub.1 -C.sub.6 alkyl group, a group --CO.sub.2 R.sup.4, or a group --CONR.sup.5 R.sup.6, R.sup.4, R.sup.5 and R.sup.6 being either a hydrogen atom or a particular group, and the other is the group --CO.sub.2 R.sub.4 or the group --CONF.sup.5 R.sup.6, or R.sup.1 and R.sup.2 are coupled together to represent a 5-membered ring so formed, Y represents a particular group or atom, X represents a substituted or unsubstituted C.sub.6 -C.sub.10 aryl, C.sub.7 -C.sub.12 aralkyl, heterocyclic or heterocyclic ring-alkyl group, m and n stand for particular integers, and R.sub.3 represents a hydrogen atom, a hydroxyl group, a group --OCO.sub.2 R.sup.7, R.sup.7 being a hydrogen atom or a particular group, or a group --OCONR.sup.8 R.sup.9, R.sup.8 representing a C.sub.1 -C.sub.6 alkyl group and R.sup.9 representing a hydrogen atom or a C.sub.1 -C.sub.

Abstract: Novel derivatives of caffeic acid of the general formula (I): ##STR1## wherein X is hydrogen atom or hydroxy; R.sup.1 is hydrogen atom, a straight or branched alkyl or alkenyl having 1 to 20 carbon atoms or a group of the formula:--(CH.sub.2).sub.n --Z--R.sup.2wherein n is an integer of 1 to 10; Z is oxygen atom, vinylene residue or a single bond; and R.sup.2 is a substituted or unsubstituted phenyl or heterocyclic residue is provided. These derivatives possess 12-lipoxygenase inhibitory activity and are useful for curing and preventing circulatory diseases. A pharmaceutical composition containing said derivtive is also provided.