Synthesis, characterization and cytotoxic activity of 5,10,15,20‐tetrakis[4‐(triorganostannyloxy)phenyl]porphyrins

Abstract

5,10,15,20‐Tetrakis[4‐(triorganostannyloxy)phenyl]porphyrins, (R3SnO)4TPP [2, R = Cy (a), Ph (b), PhC(CH3)2CH2 (c)], have been synthesized by the condensation of 4‐(triorganostannyloxy)benzaldehyde, 4‐(R3SnO)C6H4CHO (1), with pyrrole in the presence of BF3 followed by oxidation by p‐chloranil and characterized by means of elemental analysis, IR, UV–visible and NMR (1H, 13C and 119Sn) spectra. The results of X‐ray single‐crystal diffraction show that 1a and 1b possess a trans‐C3SnO2 trigonal bipyramidal geometry with the axial positions occupied by the phenolate oxygen and formyl group oxygen of an adjacent molecule and form a one‐dimensional zigzag chain. In 2a, the macrocyclic core of the porphyrin is coplanar and each tin atom possesses a distorted tetrahedral geometry. These compounds (1 and 2) have potent in vitro cytotoxic activity against two human tumor cell lines – CoLo205 and MCF‐7 – and the activity decreases in the order Ph > Cy > PhC(CH3)2CH2 for the R group bound to tin. Copyright © 2013 John Wiley & Sons, Ltd.