2-Ethoxy-3-phenyl-6,7,8,8a-tetrahydro-5H-[1,3]oxazolo[3,2-a]pyridine AIDS-147774 AIDS147774 Ethyl 3-phenyl-6,7,8,8a-tetrahydro-5H-[1,3]oxazolo[3,2-a]pyridin-2-yl ether NSC677925