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)_nL, where R=Me, Bu, Ph, Bz; L¹=5‐Hydroxy‐1,4‐naphthoquinone; L²=2‐Hydroxy‐1,4‐naphthoquinone; L³=5,8‐dihydroxy‐1,4‐naphthoquinone; n=1 for L¹ & L² n=2 for L² and L³. The compounds were synthesized by reacting the triorganotin hydroxide with the parent hydroxy‐quinone and were characterized by IR, ¹H‐, 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.

Keywords:

• hydroxy‐naphthoquinones
• triorganotins
• SRB assay

We thank Mr. Sidiropoulos and Associate Professor Mrs. Lalia‐Kantouri for acquiring the thermal analysis data and Assistant Professor Mrs. A. Kourounakis for providing the ¹H‐NMR spectra.