Synthesis and X-ray structure analysis of cytotoxic heptacoordinate sulfonamide salan titanium(iv)-bis-chelates

Abstract

A series of novel sulfonamide substituted heteroleptic salan titanium(IV)-bis-chelates complexed to 2,6-pyridinedicarboxylic acid were synthesized, structurally characterized and evaluated for their anticancer activity against two human carcinoma cell lines. All cytotoxic complexes showed complete inhibition of cell growth at active concentration, two complexes based on pyrrolidine and azepane substituted sulfonamides displayed IC₅₀ values below 1.7 μM and are more cytotoxic than cisplatin in both tested cell lines. The azepane substituted complex [L3Ti(dipic)] exhibited excellent activity with an IC₅₀ value of 0.5 ± 0.1 μM in Hela S3 and 1.0 ± 0.1 μM in Hep G2.