合成路线1

Condensation of (R)-3-(tert-butoxycarbonylamino)butyric acid (II) with hydroxyester (I) using DCC and DMAP provided compound (III). Removal of the allyl group of (III) was then effected by treatment with Pd(PPh3)4 and N-methylmorpholine (NMM) to afford acid (IV). Subsequent coupling of (IV) with alcohol (V) in the presence of DCC and DMAP yielded the corresponding ester (VI). After deprotection of the trichloroethyl ester with Zn in AcOH group (VII), and subsequent deprotection of the N-tert-butoxycarbonyl group with trifluoroacetic acid, the resulting amino acid compound (VIII) was cyclized by treatment with FDPP in the presence of diisopropylethylamine to provide lactam (IX). Finally, epoxidation of the styrene olefin with m-chloroperbenzoic acid in CH2Cl2 furnished a mixture of diastereoisomeric epoxides, from which the title compound was isolated by reverse-phase HPLC.