Reaction catalyzed by delphinidin 3,5-di-O-glucoside 3'-O-glucosyltransferase (2.4.1.238)

		+			=			+
	UDP-alpha-D-glucose	+		delphinidin 3-O-glucosyl-5-O-(6-O-caffeoylglucoside)	=		UDP	+		delphinidin 3-O,3'-O-di-beta-D-glucosyl-5-O-(6-O-caffeoyl-beta-D-glucoside)