合成路线1

The intermediate stannane derivative (XVI) has been obtained as follows: The esterification of propynoic acid (XII) with diphenyldiazomethane (XIII) in benzene gives the corresponding ester (XIV), which is then condensed with Me3Sn-Cu(CN)Li (XV) in THF/methanol to yield the desired intermediate (XVI). 3-Hydroxy-2(S)-methylpropionic acid methyl ester (I) is converted into the chiral tosylate (II) by conventional methods. The condensation of (II) with 4-pentenylmagnesium bromide (III) in THF gives the chiral tetrahydropyranyl ether (IV), which is condensed with the phosphonate (V) by means of KHMDS in THF/toluene yielding the chiral nonenoic ester (VI). The reduction of (VI) with DIBAL in the same solvent, followed by protection of the resulting alcohol with TBDPSCl and TEA in dichloromethane affords the protected diol (VII). The selective elimination of the THP protecting group, followed by reaction with TsCl and TEA in dichloromethane affords the tosylate (VIII), which is condensed with lithium acetylide (IX) in DMSO to provide the terminal acetylene (X). The deprotection of (X) with TBAF, followed by reaction with Me3Al, Cp2ZrCl2, and I2 in THF gives the omega iodoundecadienol (XI), which is condensed with the stannane derivative (XVI) by means of PdCl2 in DMF yielding the tetradecatrienoic diphenylmethyl ester (XVII). The chiral epoxidation of (XVII) with Ti(OiPr)4, BuOOH and (R,R)(+)-diisopropyl tartrate (DIPT) in dichloroethane affords the hydroxymethyl-oxirane (XVIII), which is oxidized with tetrapropylammonium perruthenate (TPAP) to provide the oxirane carbaldehyde (XIX).