4,4',6‐TRIMETHYLANGELICIN, A NEW VERY PHOTOREACTIVE AND NON SKIN‐PHOTOTOXIC MONOFUNCTIONAL FUROCOUMARIN

Abstract

Abstract— 4,4',6‐Trimethylangelicin is a new monofunctional furocoumarin which appears to be a very promising potential agent for the photochemotherapy of psoriasis. Actually, it is capable of photoreacting with DNA to a large extent (four times more than 8‐MOP), forming only monoadducts; it produces singlet oxygen to an insignificant extent. Its antiproliferative effect (tested in Ehrlich ascites tunior cells) appears to be several times higher than that induced by the most active angelicins now known and by 8‐MOP itself. In spite of this high photosensitized effect, 4,4',6‐trimethylangelicin seems to be non‐phototoxic on guinea‐pig skin and much less mutagenic than 8‐MOP in E. coli WP2 uvr ‐A, a strain in which cross‐links show lethality rather than mutations.