合成路线1

A new total synthesis of (-)-quinocarcin has been reported: The condensation of 2-bromo-3-methylanisole (I) with 4-O-benzyl-2,3-O-isopropylidene-D-threose (II) by means of butyllithium in ether followed by oxidation with CrO3-pyridine gives the ketone (III), which is debenzylated by hydrogenation over Pd(OH)2 to yield the ketol (IV). The protection of the hydroxy group of (IV) with methoxymethyl chloride affords the fully protected ketone (V), which is condensed with suitable optically active pyrrolidine (VI) by means of lithium diisopropylamide, followed by oxidation with CrO3-H2SO4 to give the diketone (VII). The cyclization of (VII) with ammonia in THF yields the isoquinoline (VIII), which is reduced with sodium cyanoborohydride to the tetrahydro derivative (IX). The protection of the imino group of (IX) with 2,2,2-trichloroethyl chloroformate yields the trichloroethyl ester (X).