(15S)Hydroxy-9alpha,11alpha-(epoxymethano)prosta-5,13-dienoic acid 42935-17-1 9,11-Epoxymethano-pgh2 PGH 2 Prosta-5,13-dien-1-oic acid, 9,11-epidioxy-15-hydroxy-, (5Z,9alpha,11alpha,13E,15S)- Prostaglandin H2