Teonicon, Bracco, Italy ,1975
77 g 7-(β-bromoethyl)-theophylline (C.A. 50, 12071f) and 57.8 g 3picolylamine in 750 ml toluene were refluxed 16 hours with vigorous agitation. The 3-picolylamine hydrobromide formed was filtered off, and the filtrate was evaporated in a vacuum to about one-third of its original volume. About 300 to 400 ml diisopropyl ether were added, and the solution was seeded with a few pure crystals of the desired product.
7-(β-3'-picolylaminoethyl)-theophylline crystallized over a period of a few hours. It was filtered off with suction, washed with a little diisopropyl ether, and dried. The yield of crude product was 69.3 g (82%), its MP 103° to 106°C. The MP was 111° to 112°C after recrystallization from isopropyl acetate. The compound was identified by microanalysis.
39.3 g 7-(β-3'-picolylaminoethyl)-theophylline were dissolved in 300 ml boiling isopropanol, and 15.4 g nicotinic acid were added to the solution in which the acid promptly dissolved. The nicotinate formed crystallized after a short time. It was filtered with suction and dried. The yield was 52.3 g (95.5%). The MP of 159° to 160°C was not significantly changed by recrystallization from ethanol.
