合成路线1

Synthesis of the target compound: The condensation of the butenoic ester intermediate (VIII) with the intermediate octadienal derivative (XXXI) by means of (+)-Ipc2BCl , TEA and H2O2 in ethyl ether gives the linear adduct (XXXII), which is silylated with Tbdms-OTf and lutidine to yield the fully protected intermediate (XXXIII). The reduction of the ester group of (XXXIII) with DIBAL gives the alcohol (XXXIV), which is oxidized with DMP and NaClO2 to yield the carboxylic acid (XXXV). The selective deprotection of the Pmb ether of (XXXV) by means of DDQ in dichloromethane affords the hydroxyacid (XXXVI), which is submitted to cyclization by means of DEAD and PPh3 in benzene to provide the macrolactone (XXXVII). The methylenation of the ketonic group of (XXXVII) by reaction with Zn, PbI2, TiCl4 and CH2I2 in THF gives the exomethylene derivative (XXXVIII), which is desilylated by treatment with HF and pyridine in THF to yield the immediate precursor (XXXIX). Finally, this compound is selectively epoxidized by reaction with (+)-DIPT, tBuOOH and Ti(OiPr)4 in dichloromethane to afford the target Laulimalide