合成路线1

Swern oxidation of N-Boc-S-valinol (I) provided aldehyde (II). After conversion of (II) to the corresponding oxime (III) upon treatment with hydroxylamine, chlorination with N-chlorosuccinimide gave the hydroximinoyl chloride (IV). Reaction of ethyl 2-(bromomethyl)acrylate (V) with phenyllithium (VI) in the presence of CuCN produced ethyl 2-benzylacrylate (VII). The dipolar cycloaddition of the nitrile oxide generated from (IV) to acrylate (VII) furnished the isoxazoline (VIII) as a diastereomeric mixture. The N-Boc protecting group of (VIII) was then cleaved with trifluoroacetic acid to give amine (IX), which was coupled with 2-naphthoic acid (X), yielding amide (XI). The carboxylic acid (XII), resulting from the basic hydrolysis of ethyl ester (XI), was then coupled with the glutamate ester (XIII) to give (XIV).