Biomimetic synthesis of monoterpenoid indole alkaloids from aglucones of secologanin derivatives : pH controlled product selectivity

Variation of the pH for hydrolysis of secologanin derivatives with beta-glucosidase controls rearrangement of the aglucone to afford different products, and hence stercoselective syntheses of heteroyohimbine, yohimbine and Aspidosperma-type alkaloids; with bakerʹs yeast chemoselective reduction can also be achieved to give a precursor for antirhine and related alkaloids.