Disclosed herein are novel prostaglandin I.sub.2 (PGI.sub.2) derivatives exhibiting excellent in vivo duration and activities, said derivatives being represented by the general formula: ##STR1## wherein R.sub.1, X, R.sub.2 and R.sub.3 are as defined herein.
An efficient and useful synthesis of isocarbacyclins, potent carbon analogs of Prostacyclin(PGI2), has been accomplished.Three synthetic routes to isocarbacyclins using intramolecular thermal ene reaction or intramolecular aldol condensation as a key step are described.
Stereocontrolled synthesis of exocyclic olefins using arene tricarbonyl chromium complex-catalyzed hydrogenation. I. Efficient synthesis of carbacyclin and its analogs.
An efficient synthesis of carbacyclin and its analogs (2-7) is described in which the stereospecific 1,4-hydrogenation of a 1,3-diene to an internal monoene plays a key role. That is, arene.Cr(CO)3 complex-catalyzed 1,4-hydrogenation of the dienes 13 and 58, obtainable from the Corey lactone in good yields, under high H2 pressure afforded the exocyclicolefins 14 and 61 stereospecifically in excellent
15-Cycloalkyl-prostaglandins of the formula:- ##STR1## wherein A represents a grouping of the formula:- ##STR2## X represents ethylene of cis-vinylene, Y represents ethylene or trans-vinylene, B represents ethylene or trans-vinylene, R represents hydrogen or alkyl of 1 through 4 carbon atoms, R.sup.1 represents cycloalkyl of 4 through 7 carbon atoms, and R.sup.2 represents hydrogen or alkyl of 1 through 12 carbon atoms, are new compounds possessing the useful pharmacological properties typical of prostaglandins; they are of especial interest in the inhibition of blood platelet aggregation.
Bicyclo[3.3.0]octane derivatives of the formula;
[wherein Ac represents an acetyl group, THP represents a tetrahydropyran-2-yl group and R represents a formyl group or a group of the formula:
(in which one of R1 and R2 represents a hydroxy group and the other represents a hydrogen atom, or R' and R2 together represent an oxo group, R3 represents a single bond or a straight- or branched-chain alkylene group of 1 to 5 carbon atoms and R4 represents a straight- or branched-chain alkyl group of 1 to 8 carbon atoms, a straight- or branched-chain alkenyl or alkynyl group of 2 to 8 carbon atoms, a cycloalkyl group of 4 to 7 carbon atoms either unsubstituted or substituted by at least one straight- or branched-chain alkyl group of 1 to 8 carbon atoms or represents a phenyl group or phenoxy group either unsubstituted or substituted by at least one halogen atom, trifluoromethyl group or straight- or branched-chain alkyl group of 1 to 4 carbon atoms, and the double bond in the formula VIII is E; with the proviso that when R3 represents a single bond, R does not represent a . substituted or unsubstituted phenoxy group)] are useful as important intermediates for the preparation of 6,9-methano-PGl2 and derivatives thereof.