Tin thiocarbonohydrazone complexes: synthesis, crystal structures and biological evaluation

Abstract

In this article, three organotin complexes formulated as [(Me)₂Sn(H₂L¹)] (1), [(Ph)₂Sn(H₂L¹)]·MeOH (2) and [(Me)₂Sn(HL²)(OAc)]₄(Me)₂O (3) (H₄L¹ = bis(2-hydroxybenzaldehyde) thiocarbohydrazone and H₂L² = bis(2-acetylpyrazine) thiocarbonohydrazone) have been synthesized and structurally characterized. Growth inhibition assays indicated that both the proligands and the three complexes are capable of showing anticancer activity against the human hepatocellular carcinoma HepG2 cells with H₂L² and complex 3 showing much higher cytotoxic potential. Subsequent toxicity studies on normal QSG7701cells showed that complex 3 has the highest tumor cell selectivity, and its IC₅₀ value on QSG7701 cells is 8.48 fold higher than that in HepG2 cells. In acute toxicity experiments, complex 3 produces a dose-dependent effect in NIH mice with a LD₅₀ value of 17.2 mg kg⁻¹.