AIDS-134789 AIDS134789 NSC633552 Spiro[4H-1-benzothiopyran-4,2'-imidazolidine]-2,3-dicarboxylic acid, 4a,7,8,8a-tetrahydro-7,7-dimethyl-5-(methylthio)-1',3'-bis(phenylmethyl)-, dimethyl ester