PHARMACEUTICALLY USEFUL PROSTENOIC ACID DERIVATIVES

摘要

1506755 Prostaglandins SANKYO CO Ltd 21 May 1975 21845/75 Heading C2C The invention comprises prostaglandins of the Formula I wherein R2 and R3 each are C 1-4 alkyl and R4 is H or C 1-4 alkyl and pharmaceutically acceptable salts thereof where R4 is H, and their preparation. The prostaglandins are obtained by removing the carbonyl protecting groups from compounds of the Formula II which are made by reducing the corresponding 15-oxo compounds, resulting from the reaction between compounds of the formula with the appropriate cyclopentanecarboxaldehydes. Methyl 7-(5,5 - ethylenedioxy - 2# - formyl - 3α- methyl - 1α- cyclopentyl)heptanoate is prepared by oxidizing methyl 7 - (5,5 - ethylenedioxy - 2#- hydroxymethyl - 3α- methyl - 1α- cyclopentyl) heptanoate, resulting from the reaction between ethylene glycol and methyl 7 - (2# - hydroxymethyl - 3α- methyl - 5 - oxo - 1α- cyclopentyl) heptanoate, which is obtained by treating 2# - hydroxymethyl - 1α- (6 - methoxycarbonylhexyl) - 3α- methyl - 5 - oxo - 1# - cyclopentanecarboxylic acidγ-lactone with bases, the lactone being obtained by reacting ethyl 7-iodoheptanoate with 2# - hydroxymethyl - 3α- methyl - 5- oxo - 1# - cyclopentanecarboxylic acidγ-lactone, resulting from reacting potassium t-butoxide with 3# - ethoxycarbonyloxymethyl - 4α- methylcyclopentan - 1 - one, which is prepared by hydrolysing 3# - ethoxycarbonyloxymethyl - 4α- methylcyclopentan - 1 - one ethylene acetal, obtained by reacting ethyl chloroformate with 3# - hydroxymethyl - 4α- methylcyclopentan- 1 - one ethylene acetal, the latter being obtained by reducing ethyl 8α-methyl-1,4-dioxaspiro[4,4]nonane - 7# - carboxylate, which is prepared by reacting sodium ethoxide with ethyl 8α- methyl - 1,4 - dioxospiro[4,4]nonone - 7α- carboxylate, obtained by reacting ethylene glycol with ethyl 2α- methyl - 4 - oxo - 1α- cyolopentanecarboxylate, which is prepared by treating 2#- methoxycarbonyl - 3α- methyl - 4α- ethoxycarbonylcyclopentanone with sodium iodide and glacial acetic acid. Pharmaceutical compositions, suitable for oral and parenteral administration, contain the above prostaglandins or salts thereof together with pharmaceutical carriers or diluents. The compounds possess anti-ulcerogenic activity.