Tetrahydrofurans are an important class of five-membered oxygen heterocycles often present in a great variety of natural products [1] and as synthetic compounds exhibit biological activity.[2] Among their industrial applications they are widely used in cosmetic formulations, perfumes and flavors.[3] As examples, mucoxin is a natural product with high potential as specific antitumor agent against breast carcinoma.[4] Furans 1a, 1b and 1c ...