cleavage product
3.MPP-a was oxidized with OsO 4 in THF containing catalytic pyridine at 0 ℃ and followed by glycol cleavage with sodium periodate in aqueous THF to give the methyl pyropheophorbide-d (MPP-d) which was reacted with carbon tetrabromide and triphenylphosphine to generate gem-dibromine substituted product at 3 b-position.
4.Experimental results showed that obvious interaction between Cu(phen)_2 2+ complex and 6-MP occurs. Their binding product has an enhanced interaction with calf thymus DNA compared with that in the absence of 6-MP due to partly intercalative effect. At the same time, 6-MP and Cu(phen)_2 2+ enhanced the pBR322 DNA cleavage by H_2O_2 and ascorbic acid.

