AIDS-142703 AIDS142703 Acetic acid 2,3,4-triacetoxy-1-(2-ethoxy-5-methylsulfanyl-[1,3,4]thiadiazole-3-carbonyl)-5-(2-ethoxy-5-methylsulfanyl-[1,3,4]thiadiazol-3-yl)-5-oxo-pentyl ester NSC660238