Enantioselective Total Synthesis of 1,3-Disubstituted β-Carboline Alkaloids, (-)-Dichotomine A and (+)-Dichotomide II.

( S)-(-)-Dichotomine A and its enantiomer were synthesized from the key intermediate, methyl 1-(1-hydroxyethyl)-β-carboline-3-carboxylate, by enantioselective esterification with Lipase QLM. The first total synthesis of (+)-dichotomide II and its enantiomer were also achieved from ( S)-(-)-dichotomine A methyl ester and its enantiomer. The absolute configuration of the stereogenic center of the reported (+)-dichotomide II was determined to be R. [ABSTRACT FROM AUTHOR]