合成路线1

The debenzylation of the chiral aldehyde (I) with BCl3 in dichloromethane gives the hydroxymethyl aldehyde (II), which is treated with Ac2O and TEA in dichloromethane to yield the acetoxymethyl aldehyde (III). The reductocondensation of (II) with the furoindoline (IV) by means of NaBH(OAc)3 and Sn(OTf)2 in 1,2-dichloroethane affords adduct (V) which is deacetylated by means of K2CO3 in methanol providing the hydroxymethyl derivative (VI). The oxidation of (VI) with DMP in dichloromethane gives the aldehyde (VII), which is alkylated with EtBr and NaH in THF and treated with Ac2O TEA and DMAP to give the acetoxy compound (VIII). The dihydroxylation of the double bond of (VIII) with OsO4 and NMO, followed by a treatment with K2CO3 in methanol yields the trihydroxy compound (IX), which is submitted to a Swern oxidation to afford the triketonic compound (X). The cyclization of (X) with DBU in benzene provides the cyclopentenedione derivative (XI), which is finally deprotected with TBAF in THF to afford the target compound.