1,1-Dimethylethyl 6-[[[(4-chlorophenyl)methyl]amino]carbonyl]-9'-(4-morpholinylmethyl)-7'-oxospiro[piperidine-4,2'(3'H)-[7H]pyrido[1,2,3-det][1,4]benzoxazine]-1-carboxylate AIDS-115473 AIDS115473