Oxydative Umwandlung von 17‐Alkoxy‐aspidospermidin‐Derivaten in 17, 17‐Dialkoxy‐17, 18‐dihydro‐1, 18‐dehydro‐aspidospermidine

Treatment of 17‐alkoxy‐aspidospermidine derivatives with iodine and sodium hydroxide in methanolic or ethanolic solution yields the corresponding 17, 17‐dialkoxy‐17, 18‐dihydro‐1, 18‐dehydro‐aspidospermidine. Hence compounds 1 and 2 in methanol give the oxidation products 8 and 3 , respectively. In ethanol, 4 is converted to 5 , 2 to a mixture of 6 and 7 ; 4 in methanol yields a mixture of 6 and 7 in a different ratio.