Anomalous mass spectra of some aporphine methiodides

Abstract

Methiodides of corydine, isocorydine and isothebaine are O-demethylated in the ionic source of the mass spectrometer by hydrogen iodide formed on pyrolysis of the sample. The reaction is common in aporphine methiodides substituted in positions 1 and 11 by one hydroxyl and one methoxyl group. The behaviour can be explained by the combined action of the hydrogen bridge and steric strain.

Aporphinoid Alkaloids, IV

“…[a]D: +62°(r = 0.18, MeOH) (123) UV: 275, 315 sh (123) NMR: IR: 3500,3420,3250 (218) MS: 325 (3), 311(15), 297 (10), 296 (7), 294 (4), 280 (9) , 254 (14), 240 (31), 226 (6), 225 (15), 207 (10) , 197 (9), 142, 127, 58 (100) ( ) (67) SOURCES: Papaveraceae: Papaver bracteatum (220),…”