Synthesis and Cellular Studies of Porphyrin-Cobaltacarborane Conjugates

摘要

The total syntheses of five new porphyrin-cobaltacarborane conjugates (1-5) have been achieved in 88-98% yields in a single-step reaction between a nucleophilic meso-pyridyl-containing porphyrin and zwitterionic cobaltacarborane [3,3'-Co(8-C_4H_8O_2-1,2-C_2B_9H_(10))(1',2'-C_2B_9H_(11))].These unique zwit-terionic compounds have one to four cobaltabisdicarbollide anions conjugated to the porphyrin macrocycle via (CH_2CH_2O)_2 chains.The X-ray structure of one of these conjugates (1) is presented and discussed.The cellular uptake,cytotoxicity,and subcellular localization of cobaltacarboranepor-phyrins 1-5 were investigated in human HEp2 cells.The number and distribution of cobaltacarborane residues linked to the porphyrin macrocycle has a significant effect on the cellular uptake of the conjugates.