23,27-Epoxy-3H-pyrido[2,1-c] [1,4]oxaazacyclohentriacontine-1,5,11,28,29-pentone-, 1,4,5,6,9,10,11,12,13,14,21,22,23,24,25,26,27,28,29,31, 32,33,34,34a-tetracosahydro- 27-hydroxy-10,21-dimethoxy-3-[2-[3-methoxy-4-[1-oxo- 3-(dimethylamino)propoxy]cyclohexyl]-1-methylethyl]- 6,8,12,14,20,26-hexamethyl- 9-[1-oxo-3-(dimethylamino)propoxy]-, stereoisomer NSC643248