The condensation of trichloroacetyl-baccatin III (I) with the oxazolidine (II) by means of DCC in toluene gives the acylated baccatin (III), which is hydrolyzed with conc. HCl yielding the N-debenzoylated taxol (IV). The acylation of the free amino group of (IV) with 1-pentenylcarbonyl chloride (V) in pyridine affords the trichloroacetylated target compound (V), which is finally deprotected with ammonium acetate in MeOH/THF.