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.