Synthesis and characterization in solid and solution of trans-dichloro-1-(2′,6′-difluorophenyl)-1H,3H-thiazolo[3,4-a]-benzimidazole(tri-n-propyl-phosphine)-palladium(II)″: A palladium(II) complex of a ligand with anti-HIV properties

Abstract

The 1-(2′,6′-difluorophenyl)-1H,3H-thiazolo[3,4-a]benzimidazole (L), a highly potent nonnucleoside HIV-1 reverse transcriptase inhibitor, has been reacted with [Pd 2Cl 4(PPr 3 n) 2] in order to study its coordinating properties towards metal ions. The structure of the synthesized product has been examined in solution by 1H and 13C NMR, and in solid by X-ray analysis. [Pd(PPr 3 n)(L)Cl 2] has a trans structure and L coordinates through imine nitrogen. The loss of anti-HIV properties of L, by complexation, suggests that, unless biological inactivation is simply due to steric reasons, the imine nitrogen atom is an active site of the molecule.