合成路线1

The total synthesis of (+)-resiniferatoxin started with the asymmetric Sharpless epoxidation of 1,4-pentadien-3-ol (I) to afford the epoxy-alcohol (II), which was further protected as the benzyl ether (III). Epoxide ring opening in (III) with the lithium acetylide (IV) in the presence of BF3 at -78 ºC yielded the acetylenic alcohol (V), which was subsequently cyclized to lactone (VI) under acidic conditions. Methylation of the lithium enolate of lactone (VI) gave rise to the trans- lactone (VII) as the major diastereoisomer. Addition of the lithiated derivative of O-(tert-butyldimethylsilyl)furfuryl alcohol (VIII) to the lactone (VII) produced the furyl ketone (IX). After protection of the hydroxyl group of (IX) as the corresponding acetate ester (X), reduction of its ketone function with NaBH4 furnished alcohol (XI). Oxidation of the furan nucleus of (XI) with m-CPBA produced the intermediate diketone (XII) which spontaneously cyclized to the pyranone (XIII). Acetylation of the hydroxyl group of (XIII) gave the (acetyloxy)pyranone (XIV).