U 74500A [ 21-(4-(3,6-bis(diethylamino)-2-pyridinyl)-1-piperazinyl)-16-methylpregna-1,4,9(11)triene-3,20-dione HCl,U-74500A,U74500,U74500E,21-(4-(5,6-bis(diethylamino)-2-pyridinyl)-1-piperazinyl)-16-methylpregna-1,4,9(11)triene-3,20-dione HCl,U 74500E,U-74500E,U74500A ] potent inhibitor of iron-dependent lipid peroxidation; has excellent activity in in vivo models of experimental CNS trauma & ischemia; structure given in first source; RN given is for 3,6-bis(diethyla