2,5,6,7-tetranor-4,8-inter-m-phenylene PGI.sub.2, derivative, manufacturing process thereof and its use

A 2,5,6,7-tetranor-4,8-inter-m-phenylene PGI.sub.2 derivative having the formula:

• ##STR189## (wherein R.sub.2 represents hydrogen atom, a pharmaceutically acceptable cation or an ester residue selected from the group consisting of
• (i) a normal alkyl group having 1 to 12 carbon atoms or a branched alkyl group having 3 to 12 carbon atoms;
• (ii) --Z--R.sub.5 (wherein Z represents a valence bond or a normal or branched alkylene group defined as the formula C.sub.t H.sub.2t (t is an integer of 1 to 5 and R.sub.5 represents a cycloalkyl group with 3 to 12 ring members which is unsubstituted or substituted by 1 to 4 normal alkyl substituents containing 1 to 4 carbon atoms), wherein R.sub.2 and R.sub.4 represented by the same formula may be the same or different;
• (iii) --Z--Ar (wherein Z has the same meaning as in (ii) and Ar represents a phenyl group unsubstituted or substituted by 1 to 4 substituents selected from the group consisting of alkyl, methoxy, chloro, bromo, fluoro, iodo, trifluoromethyl, nitro, cyano, phenyl and phenoxy);
• (iv) --(CH.sub.2 CH.sub.2 O).sub.n --CH.sub.3 (wherein n is an integer of 1 to 5);
• (v) --Z--R.sub.7 (wherein Z has the same meaning as in (ii), R.sub.7 represents .alpha.-naphthyl group, .beta.-naphthyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, .alpha.-furyl group, .beta.-furyl group, .alpha.-thienyl group or .beta.-thienyl group);
• (vi) --C.sub.t H.sub.2t COOR.sub.8 (wherein C.sub.t H.sub.2t has the same meaning as in (ii);
• R.sub.8 represents methyl group, ethyl group or propyl group) or ##STR190## (wherein R.sub.9 represents hydrogen atom or benzoyl group;
• R.sub.10 represents phenyl group, p-bromophenyl group, p-chlorophenyl group, p-biphenyl group, p-nitrophenyl group, p-benzamidophenyl group or 2-naphthyl group);
• and R.sub.4 represents
• (i) a normal alkyl group having 1 to 12 carbon atoms, or
• (ii) --Z--Ar (wherein Z represents a valance-bond or a normal or branched alkylene group defined as C.sub.t H.sub.2t (wherein t is an integer of 1 to 5);
• Ar represents a phenyl group which is unsubstituted or substituted by 1 to 4 substituents selected from the group consisting of alkyl, methoxy, chloro, bromo, fluoro, iodo, trifluoromethyl, nitro, cyano, phenyl and phenoxy), or
• (iii) --Z--R.sub.5 (wherein Z has the same meaning as in (ii);
• R.sub.5 represents a cycloalkyl alkyl substituents containing 1 to 4 carbon atoms).