Synthesis, structure and in vitro biological activity of new hydroxy-naphthoquinonato triorganotin compounds

We report herein on the synthesis, structure and in vitro antitumor activity of new triorganotin compounds of the general type (R3Sn)(n)L, where R = Me, Bu, Ph, Bz; L-1 = 5-Hydroxy-1,4-naphthoquinone; L-2 = 2-Hydroxy-1,4-naphthoquinone; L-3 = 5,8-dihydroxy-1,4-naphthoquinone; n = 1 for L-1 & L-2 n = 2 for L-2 and L-3. The compounds were synthesized by reacting the triorganotin hydroxide with the parent hydroxyquinone and were characterized by IR, H-1-, NMR, and thermal measurements. The spectroscopic analysis provides evidence on the formation of a chelate ring that is responsible for the stabilization of the triorganotin cation with the Sn central atom in a five-coordinated environment exhibiting distorted trigonal bipyramidal geometry. The new compounds were tested for their cytotoxicity against five human tumor cell lines and one non-tumor human cell line and the results are reported.