Mitsunobu alkylation of cancerostatic 5-fluorouridine with (2E)-10-hydroxydec-2-enoic acid, a fatty acid from royal jelly with multiple biological activities.

5-Fluorouridine (1) - a nucleoside antimetabolite with strong cancerostatic properties - was protected i) at the 2'- and 3'-OH groups with a heptan-4-ylidene residue and ii) at the 5'-OH group with a (4-methoxyphenyl)(diphenyl)methyl residue. This fully protected compound, 3, was submitted to a Mitsunobu reaction with the N-hydroxysuccinimide (NHS) ester, 5, of (2E)-10-hydroxydec-2-enoic acid (4) which gave nucleolipid 6. The latter was detritylated with Cl2 CHCOOH to yield the co-drug 7 as NHS ester.