Figure 2.

Synthesis of the iminosugar indole alkaloids. Reaction conditions: d/l-lyxose/ribose tosylate, d-mannose tosylate, or l-rhamnose sulfonate (0.2 mmol, 1.0 equiv), aminomethyl-indole (1.2 equiv), CH₃CN (2.0 mL), air, 120 °C, 5 h, oil bath heating; ^b isolated yields; ^c determined using ¹H NMR; (dr): the dr was determined by ¹H NMR of the mixture.