Reaction catalyzed by pepsin A (3.4.23.1)

		+			=		(3R,4S)-4-(2-chlorophenyl)-3,4-dihydroxybutan-2-one
	2-chlorobenzaldehyde	+		1-hydroxypropan-2-one	=		(3R,4S)-4-(2-chlorophenyl)-3,4-dihydroxybutan-2-one