Preparation and cytotoxicity toward cancer cells of mono(arylimino) derivatives of beta-lapachone
- J Med Chem. 2001 Jul 19;44(15):2486-9. doi: 10.1021/jm010050u.
- 1. Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, (1428) Buenos Aires, Argentina.
A regio- and stereospecific synthesis of monoarylimino o-quinones derived from beta-lapachone (1) was achieved by treatment of the quinone with a slight excess of an arylamine in the presence of an excess of triethylamine/titanium tetrachloride 4:1. Imine formation occurred exclusively at position 6, giving the Z diastereomer, as determined by single-crystal X-ray analysis. In vitro tests for cytotoxicity in 55 human Cancer cell cultures showed a substantial loss in activity for the p-nitrophenylimine (5), whereas the phenylimine (2), p-methylphenylimine (3), and p-methoxyphenylimine (4) retained (or bettered) most of the cytotoxicity and selectivity of the parent quinone. Preliminary in vivo testing in hollow fiber assays against a standard panel of 12 human tumor cell lines showed that although beta-lapachone failed, compounds 2 and 3 had good scores with net cell kills.