Abstract: Object: To produce E-prostaglandins in a high yield and in a short time with suppressed formation of isomers.Structure: A process for preparing E-prostaglandins represented by the formula: ##STR1## (wherein A, R.sup.6 and R.sup.7 represent respectively an arbitrary group which does not participate in the reaction; B represents a vinylene or ethynylene group; and R.sup.4 and R.sup.5 may be the same or different from each other and each represents a hydrogen atom or a protective group of the hydroxyl group) which comprises reacting allyl esters of E-prostaglandins represented by the formula: ##STR2## (wherein R.sup.1 and R.sup.2 may be the same or different from each other and each represents a hydrogen atom or a lower alkyl group; R.sup.3 represents a hydrogen atom, a lower alkyl group, an alkenyl group or an aryl group; and A, B, R.sup.4, R.sup.5, R.sup.6 and R.sup.

Abstract: Object: To provide novel prostaglandin E.sub.1 analogues which have more excellent pharmaceutical effects, longer duration of the effects and less side-effects than the prior art prostaglandin E.sub.1 's.Constitution: A PGE.sub.1 analogue represented by the formula: ##STR1## (wherein A is a vinylene group or an ethynylene group, R.sup.1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an allyl group, R.sup.2 is a branched aliphatic hydrocarbon group having 5 to 10 carbon atoms), or a salt thereof.

Abstract: A prostaglandin derivative represented by the formula: ##STR1## wherein X is halogen atom R.sup.1 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R.sup.2 is a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkylmethyl group having 4 to 10 carbon atoms or a cycloalkylethyl group having 5 to 12 carbon atoms, or a salt thereof, which has an excellent lowering action of intraocular pressure and improving actions of renal diseases, ischemic heart diseases and heart failure.

Abstract: A prostaglandin E.sub.1 analogue represented by formula ##STR1## wherein R.sup.1 represents a hydrogen atom or a C.sub.1 -C.sub.6 alkyl group; and X is an oxygen atom and R.sup.2 represents ##STR2## or X is a sulfur atom and R.sup.2 represents ##STR3## The compound has a strong and prolonged inhibitory action for platelet aggregation and is useful for treatment of various thrombotic diseases including peripheral circulatory disturbance.

Abstract: A prostaglandin derivative represented by formula ##STR1## wherein R.sup.1 represents a hydrogen atom or a C.sub.1 -C.sub.6 alkyl group, and R.sup.2 represents a cyclohexyl group or a cyclopentylmethyl group. This compound has physiological activities such as platelet aggregation-inhibiting action, renal blood vessel and coronary blood vessel-dilating actions and the like, and is useful for treatment of renal failure and diseases of circulatory organs.

Abstract: ObjectNovel PG derivatives having an excellent platelet aggregation inhibition activity are provided.ConstructionProstaglandin derivatives represented by formula: ##STR1## and salts thereof.

Abstract: Object: To provide novel prostaglandin E.sub.1 analogues which have more excellent pharmaceutical effects, longer duration of the effects and less side-effects than the prior art prostaglandin E.sub.1 's.Constitution: A PGE.sub.1 analogue represented by the formula: ##STR1## (wherein R.sup.1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an allyl group, and R.sup.2 is an alkyl group having 3 to 6 carbon atoms, an alkenyl group having 3 to 6 carbon atoms), or a salt thereof.