Cycloaddition reactions of pristine and endohedral fullerene molecules: possible anticancer activity.

Epoxide of oestradiol is one of the main risk factors for the genesis and evolution of breast cancer; hence, in recent years there has been considerable interest in the investigation of new inhibitors capable of reducing its carcinogenic activity. The aim of this article is to study the [2 + 2] cycloaddition reaction of epoxide of oestradiol in different pristine (C and D-C) and endohedral metallofullerene (C@ScC, C@Sc and C@Sc) by means of molecular electrostatic potential (MEP) topological analysis. Different from other molecular scalar fields, MEP topology enables to find minima related to lone pairs and π electrons, therefore, this molecular scalar field is appropriate to identify the most reactive sites.