Structure and properties of the dispersions of multi-walled carbon nanotubes in N,N-dimethylacetamide

Effective methods for preparation of tetrazole-contaminating biscaroxylate complexes of platinum (II) were developed and novel oxalate, malonate and succinate platinum (II) complexes with 1-R- and 2-R-5-ammotetrazoles (R= l-CH_3,2-CH_3,1-C₆H₅, 2-t-C₄H₉), analogues of third-generation antitumor platinum drugs were prepared. Studies of the obtained complexes showed their stability- in solution, which is sufficient for biological studies. Cell proliferation tests and bioanalytical studies showed that increasing the hydrophobicity of substituents at the tetrazole heteroring leads to an increase in the intracellular concentration of complexes followed by a growth of their cytotoxic activity. Two platinum oxalate complexes with 5-amino-1-phenyl- and 5-amino-2-tert-butyltetrazoles having m-configuration were chosen as leader compounds featuring the best combination of the antiproliferative activity, lipophilicity, and solubility. (authors)