合成路线1

A stereocontrolled total synthesis of vinblastine has been reported. 3-Ethyl-5-phenyl-4-pentenal (I) is transformed into cyanohydrin (II), which is further acetylated with Ac2O in pyridine to furnish the racemic alpha-acetoxy nitrile (III). Enzymatic hydrolysis of cyanohydrin acetate (III) leads to (S)-cyanohydrin (IV) as a mixture of diastereomers at the 4-ethyl group. Ozonolysis of (IV) produces the cyclic hemiacetal (V), which is subsequently dehydrated to the dihydrofuran (VI) employing mesyl chloride and triethylamine. The cyano group of (VI) is then reduced to the primary amine (VII) with LiAlH4 in THF. Acylation of amine (VII) with 2,4-dinitrobenzenesulfonyl chloride leads to the corresponding sulfonamide (VIII) (8).