Base product, xxviii

Under the influence of sulfuric acid, acetic anhydride introduces an acetyl group into the 6 -position of papaverine (49). The reaction product, 6 -acetylpapaverine (XXVII), is a neutral pseudobase, which rearranges slowly in aqueous alcoholic solution to the alkaline quaternary base coralyn (XXVIII) related to dehydrocorydaline. An isomer of the natural alka-MeO... 

Upon treatment with tosyl chloride in pyridine, a quaternary salt (XXVI) was produced (5). The quaternary base was reconverted into iboxygaine by aqueous sodium hydroxide (33). With sodium ethylate, on the other hand, 20-ethoxyibogair.e [XXVII, iboxygaine ethyl ether, y-isomer of Stauffacher and Seebeck (16)], mp 194°-196°, [a]D —16° (EtOH), was the major product (33). In both the preceding reactions, d20-ibogaine (XXVIII), mp 155°-156°, [a]D —80° (EtOH), was also... 

Rascovic and Marinkovic (1978) [191] treated PAN fiber in SO2 for 3 h at 230°C and then for 1 h at 290°C. The fiber reacted slowly at low temperatures, the rate increasing towards 230°C and becoming rapid at 290°C, to give a cyclized and aromatized product with an increased diameter. Based on DTA, IR and elemental analysis, they proposed the following structure (Scheme XXVIII) ... 

---