material. Compound 5 was converted in three steps to trans-ester 8. Acid-catalysed epimerization of 8, lithium aluminum hydride reduction of the ester group, tosylation and substitution with cyanide gave the cis-nitrile 12. Acid-induced cyclization of 12 yielded mainly (±)-trans-11-methoxydeethyleburnamonine (13), whereas base-induced cyclization gave (±)-cis-11-methoxydeethyleburnamonine (4).