合成路线1

The silylation of 3(S)-hydroxytetrahydrofuran-2-one (I) with TBDMS-Cl and imidazole gives the silyl ether (II), which is methylated with MeLi in THF yields the 3(S)-(TBDMSO)-5-hydroxy-2-pentanone (IV), through the hemiketal intermediate (III). Simultaneously, the cyclization of 1,3-dichloropropanone (V) with thioacetamide (VI) in refluxing ethanol affords 4-(chloromethyl)-2-methylthiazole (VII), which is treated with tributylphosphine to provide the phosphonium salt (VIII). The condensation of (VIII) with the ketone (IV) gives the unsaturated alcohol (IX), which is oxidized to the corresponding aldehyde (X) by means of oxalyl chloride in DMSO. The condensation of (X) with 2-phosphonopropionic acid triethyl ester (XI) by means of KHMDS gives the dienoic acid ethyl ester (XII), which is reduced with DIBAL in THF yielding the corresponding primary alcohol (XIII). The condensation of (XIII) with the chiral sulfone intermediate (XIV) by means of KHMDS and PPh3 affords the corresponding adduct (XV), which is desulfurized with Na/Hg in THF/methanol giving the silylated diol (XVI). The selective monodesilylation of (XVI) with CSA in methanol/dichloromethane yields the primary alcohol (XVII), which is oxidized with Dess Martin periodinane (DMP) to the aldehyde (XVIII). The condensation of (XVIII) with the intermediate chiral ketone (XIX) by means of LDA in THF affords the hydroxy ketone (XX).