Cytotoxic activity of new racemic and optically active N-phosphonoalkyl bicyclic [beta]-amino acids against human malignant cell lines

The cytotoxic effects of novel racemic and optically active constrained N-phosphonoalkyl bicyclic [beta]-amino acids were tested against a panel of human tumor cell lines. All of the compounds investigated exhibited different concentration-dependent antiproliferative effects against the HT-29, MDA-MB-231, HepG2 and HeLa cell lines after 24 h treatment. The most sensitive cells were the HeLa cells at various concentrations of the four compounds tested. The aminophosphonate 3 exerted the most pronounced antiproliferative effect against the HeLa cells (inhibition of the cell vitality up to 70% at 0.5 mg/ml) and was not toxic to the normal Lep3 cells at lower concentration. Furthermore, the N-phosphonophenyl derivatives 1 and 2 displayed antiproliferative effect against mainly the MDA-MB-231 tumour cells at higher concentration.