The present invention provides cyclopentane heptanoic acid, 2 heteroaryl alkyl or alkenyl derivatives which may be substituted in the 1-position with hydroxyl, alkyloxy, amino and amido groups, e.g. 1-OH cyclopentane heptanoic acid, 2 heteroarylalkenyl derivatives. In particular, these derivatives are 7-[5-hydroxy-2-(heteroatom-substituted hydroxyhydrocarbyl)-3-hydroxycyclopentyl] heptanoic or heptenoic acids and amine, amide, ether, ester and alchohol derivatives of said acids wherein one or more of said hydroxy groups are replaced with an ether group. These compounds are potent ocular hypotensive and are particularly suited for the management of glaucoma. Moreover, the compounds of this invention are smooth muscle relaxants with broad application in systemic hypertensive and pulmonary diseases; with additional application in gastrointestinal disease, reproduction, fertility, incontinence, shock, inflammation, immune regulation, disorder of bone metabolism, renal dysfunction, cancer and other hypoproliferative diseases.