AIM: To derive a model that could be used in drug design. METHODS: Beta-carbolines are reported to have antitumor activities on cultured cancer cell lines. A comparative molecular field analysis (CoMFA) was undertaken to elucidate the correlation of cytotoxities and structural parameters of 16 beta-carboline analogs (1-16). The compound 12 was finally used as a template for the other compounds in the dataset because of its highest biological activity. RESULTS: The CoMFA applied to the final alignment resulted in a qcv of 0.656 and it showed that the 2 steric fields contributed 43.3 % of the model information while the electrostatic fields represented the other 56.7 %. CONCLUSION: Three designed compounds, which were predicted to have high, moderate and low activities respectively, were synthesized. The IC50 values of these compounds indicated the significance of the analysis in this study. The model derived from the current study could be further used in design for more active compounds. AIM: To derive a model that could be used in drug design. METHODS: Beta-carbolines are reported to have antitumor activities on cultured cancer cell lines. A comparative molecular field analysis (CoMFA) was undertaken to elucidate the correlation of cytotoxities and structural parameters of 16 beta-carboline analogs (1-16). The compound 12 was finally used as a template for the other compounds in the dataset because of its highest biological activity. RESULTS: The CoMFA applied to the final alignment resulted in a qcv of 0.656 and it showed that the 2 steric fields contributed 43.3% of the model information while the electrostatic fields represented the other 56.7%. CONCLUSION: Three designed compounds, which were predicted to have high, moderate and low activities respectively, were synthesized. The IC50 values of these compounds indicates the significance of the analysis in t his study. The model derived from the current study could be further used in design for more active compounds.