A semi-empirical study on the electronic structure of ellipticines

Ellipticine and some of its derivatives are organic molecules with intense antitumor activity. In this work we report a semiempirical study on the ele ctronic structure of ellipticine and some derivatives. Geometrical and spec troscopic aspects were investigated through the use of the well-known PM3 ( Parametric Method 3) and ZINDO (Zerner's Intermediate Neglect of Differenti al Overlap) methods. Comparing PM3 and previously reported AM1 (Austin Meth od One) results, we found out that overall PM3 results are better. The ZIND O simulated absorption spectra compare well to the available experimental d ata. We have observed a very simple correlation between the dipole moment v alue (DM) and the antitumor activity. These results suggest a way to improv e and design new antitumor ellipticine derivatives, as well as, to select p romising molecules from untested groups. (C) 1999 Elsevier Science B.V. All rights reserved.