合成路线1

Mitsunobu coupling of geranylgeraniol (I) with N-hydroxyphthalimide (II) in the presence of diethyl azodicarboxylate and triphenylphosphine produced the N-alkoxyphthalimide (III). Subsequent hydrazinolysis of the phthaloyl group of (III) gave rise to the O-alkyl hydroxylamine (IV). (2-Diethylphosphono)butyric acid (VI), prepared by partial hydrolysis of triethyl ester (V), was then coupled with hydroxylamine (IV) using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide-HCl and 1-hydroxybenzotriazole to furnish the N-alkoxyamide (VII). The phosphonate ester groups were finally cleaved by treatment with bromotrimethylsilane and 2,4,6-collidine.