Reaction catalyzed by dermatan 4-sulfotransferase (2.8.2.35)

		+			=			+
	3'-phospho-5'-adenylyl sulfate	+		[dermatan]-N-acetylgalactosamine	=		adenosine 3'-5'-bisphosphate	+		[dermatan]-4-O-sulfo-N-acetylgalactosamine