Quantitative Structure-Cytotoxicity Relationship of 2-(N-cyclicamino)chromone Derivatives

4H-1-Benzopyran-4-ones (chromones) have provided backbone structure for the chemical synthesis of potent anticancer drugs. In this study, the cytotoxicity of fifteen 2-(N-cyclicamino)chromone derivatives was investigated and subjected to quantitative structure-activity relationship (QSAR) analysis.

Cytotoxicity against four human oral squamous cell carcinoma cell lines and three oral normal mesenchymal cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Tumor specificity (TS) was evaluated by ratio of mean 50% cytotoxic concentration (CC₅₀) against normal oral cells to that against human oral squamous cell carcinoma cell lines. Potency-selectivity expression (PSE) value was calculated by dividing the TS value by CC₅₀ against tumor cells. Apoptosis induction was evaluated by morphological observation, western blot analysis and cell-cycle analysis. For QSAR analysis, a total of 3,089 physicochemicals, structural and quantum chemical features were calculated from the most stabilized structure optimized using Corina.

7-Methoxy-2-(4-morpholinyl)-4H-1-benzopyran-4-one (5c) showed highest tumor-specificity, comparable with that of doxorubicin, without inducing apoptosis. Tumor-specificity of fifteen 2-(N-cyclicamino) chromones was correlated with molecular shape, especially 3D-structure.

Chemical modification of 5c may be a potential choice for designing a new type of anticancer drugs.