348636-02-2

Upstream product

• 131489-59-3 (E)-methyl-4-(N-benzylamino)-but-2-enoate 
• 100-46-9 benzylamine 
• 134221-52-6 4-chloro-2,6-dimethoxypyrimidine-5-carboxaldehyde 
• 1117-71-1 methyl-4-bromo-2-butenoate 
• 212131-74-3 Methyl (E)-4-[benzyl(5-formyl-2,6-dimethoxypyrimidin-4-yl)amino]but-2-enoate 

Relevant academic research and scientific papers

Pyrimidine annelated heterocycles-synthesis and cycloaddition of the first pyrimido[1,4]diazepine N-oxides

5-Formyl- and 5-acetyl-4-(alkenylamino)pyrimidines 5 have been prepared as precursors to novel pyrimido[1,4]-diazepine N-oxides 3. In addition to cyclisation to the targeted dipoles the substrates 5 have also been observed to form imidazopyrimidines 12 and 39 via an intramolecular Michael addition; additionally 5b has been observed to form the pyrimidoazepinone 42. Aldonitrone 3a cycloadded readily to olefinic dipolarophiles; ketodipole 3b did not share this reactivity. Both dipoles reacted with acetylenic dipolarophiles but the ensuing cycloadducts 37 were unstable; facile ring contraction of their isoxazolopyrimidodiazepine skeletons to the pteridine nucleus is noted. The structure of 37c has been determined by X-ray crystallography.