(1a,9b-Dihydro-1H-phenanthro(9,10-b)azirin-1-yl)phosphonic acid diethyl ester 81593-13-7 BRN 4525822 CCRIS 2139 N-(Diethylphosphoryl)phenanthrene 9,10-imine Phosphonic acid, (1a,9b-dihydro-1H-phenanthro(9,10-b)azirin-1-yl)-, diethyl ester