Ab initio and 1H NMR study of the Zn(II) complexes of a nido- and a closo-carboranylporphyrin
2004 ◽
Vol 08
(07)
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pp. 996-1006
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An ab initio study of a promising nido-carboranylporphyrin for the boron neutron capture therapy of tumors, and of its closo precursor is reported. Base-induced deboronation of neutral ZnDCP , believed to exist as a mixture of 3 stereoisomers, produces the tetraanionic ZnDCP 4- as a complex mixture of isomers. 1 H NMR data and ab initio calculations support these findings. The position of the axial pyridine ligand in ZnDCP 4- and the orientation of the endo hydrogen atoms on the open faces of the nido-carborane cages significantly influence the total energy of the ZnDCP 4- structures. It is suggested that the "cocktail" of isomers possibly enhances the biological activity of tetra(nido-carboranyl)porphyrins, such as ZnDCP 4-.
1997 ◽
Vol 101
(8)
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pp. 1588-1594
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