Reaction catalyzed by sphingomyelin phosphodiesterase (3.1.4.12)

		+		H2O	=			+
	4-nitrobenz-2-oxa-1,3-diazole-sphingosylphosphorylcholine	+		H2O	=		4-nitrobenz-2-oxa-1,3-diazole-sphingosine	+		choline phosphate