Two routes were examined that permit conversion of 4-vinyl-2-azetidinones via intramolecular nitrile oxide-olefin or azide-olefin cycloaddition into tricyclic β-lactams. Stereoselectivity in these cycloadditions as well as further chemoselective transformation of the products were shown to be dependent on the size of the newly formed ring. ... Irradiation of the angular methyl group gave rise to a 5% enhancement for the signal attributed to one of the methylene ...
![8H-Azeto[1,2-a][1,2,3]triazolo[5,1-c]pyrazin-8-one,1,5,6,9,9a,9b-hexahydro-9a-methyl-,trans-(9CI) Structure](https://image.chemsrc.com/caspic/136/111197-30-9.png)
