Relationship between electronic structure and cytotoxic activity of azulenequinones and trihaloacetylazulenes.

The relationship between the structure and cytotoxic activity of azulenequinones and trihaloacetylazulenes was investigated based on theoretical calculations. Four different dipole moments (mu(G), mu(ESP-G), mu(W) and mu(ESP-W)) and heats of formation (DeltaH(f)) of the azulenequinones [1-27] and trihaloacetylazulenes [28a,b-40a,b] were separately calculated in gas phase and aqueous solution using the conductor-like screening model/parametric method 3 (COSMO/PM3) method. The cytotoxic activity of azulenequinones was well correlated to DeltaDeltaH(f) HOMO energy and mu(ESP-w). The cytotoxic activity of trihaloacetylazulenes was correlated to DeltaDeltaH(f) LUMO energy and mu(ESP-W). QSAR may be applicable to predict the cytotoxicity of azulenequinones and trihaloacetylazulenes.