摘要:
The synthesis and spectral characterization of the novel organotin complexes [SnBu2(ten)] (1) and [SnBu2(Hten)(2)] (2) or the potent and widely used anti-inflammatory drug tenoxicam (H(2)ten) are reported. A crystal-structure determination of 1 showed that, in this complex, the ligand is doubly deprotonated at the hydroxy O-atom and the amide N atom and is coordinated to the SnBu2 fragment via four- and six-membered chelate rings. An extended network of Sn - O - Sn, C - H ... O and C - H ... pi contacts lead to aggregation and a supramolecular assembly. Potentiometric titrations in nonaqueous solutions support the ionization of the drug by removal of the second H-atom, the amide H-atom, in the presence of thr diorganotin(IV) fragment. The K-a values of the poorly H2O-soluble drug tenoxicam were obtained spectrophotometrically in aqueous solutions of constant ionic strength.