Synonyms: Propanoicacid, 3-[[3-[(1R,2R,3R)-3-hydroxy-2-[(1E,3S)-3-hydroxy-1-octenyl]-5-oxocyclopentyl]propyl]thio]-(9CI); Propanoic acid,3-[[3-[3-hydroxy-2-(3-hydroxy-1-octenyl)-5-oxocyclopentyl]propyl]thio]-, [1R-[1a,2b(1E,3S*),3a]]-; 4-Thia-PGE1; 4-Thiaprostaglandin E1