Abstract: Novel 11-desoxy-prostaglandin F.sub.2 derivatives of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms, an alkali metal, an equivalent of an alkaline earth metal, magnesium or organic amine base, R.sub.1 and R.sub.2 are individually seleced from the group consisting of hydrogen and methyl and X is selected from the group consisting of ##STR2## and a 5 to 6 membered heterocycle optionally substituted with at least one member of the group consisting of halogen, --CN and alkyl of 1 to 5 carbon atoms and X.sup.1 is a 6 member heterocycle with the wavy lines indicating that the hydroxy may be in either one of the two possible .alpha. and .beta. positions having hypotensive activity and process for their preparation.