合成路线1

The intermediate (XVI) has been obtained as follows: The ozonolysis of (2S,3S,4S)-2,4-dimethyl-1-(tert-butyldimethylsilyloxy)-5-hexen-3-ol (I) with O3 in DMSO gives the aldehyde (II), which is condensed with phosphorane (III) to yield the chiral heptenoic acid methyl ester (IV). The reaction of (IV) with benzaldehyde (V) by means of KHMDS affords the cyclic ketal (VI), which is desilylated with HF to provide the carbinol (VII). The oxidation of (VII) in methanol gives the dimethylacetal (VIII), which is treated with CSA in methanol to yield the tetrahydropyranylacetic acid methyl ester (IX). The silylation of the OH group of (IX) with Tbdms-OTf affords the silyl ether (X), which is hydrolyzed with LiOH to the corresponding free acetic acid (XI). The condensation of (XI) with N,O-dimethylhydroxylamine (XII) by means of DCC and HOBT provides the methoxyamide (XIII), which is treated with phenylsulfanyltrimethylsilane (XIV), ZnI2 and tetrabutylammonium iodide to give the phenylsulfanyl derivative (XV). Finally, the methoxyamide group of (XV) is reduced with LiAlH4 to afford the target acetaldehyde derivative (XVI).