合成路线1

Synthesis of Weinreb amide (VII). The reaction of the chiral epoxide (I) with HOAc in THF, followed by cyclization with TsOH in methanol gives the chiral tetrahydrofuran derivative (II), which is selectively monosilylated with TBDPSCl and imidazole, yielding silyl ether (III). The silylation of (III) with Tes-Cl affords the disilylated compound (IV), which is oxidized with RuCl3 and NaIO4 in acetonitrile/CCl4/pH 8 buffer to provide the lactone (V). The reaction of (V) with N,O-dimethylhydroxylamine and Me2AlCl in dichloromethane gives the amide (VI), which is finally protected to afford the desired target intermediate (VII).