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.