5,11-Dihydro-6H-pyrido[2,3-b][1,4]benzodiazepin-6-one, can be used in the synthesis of fluorescent pirenzepine derivatives, used as potential bitopic ligands of the Human M1 Muscarinic receptor.

In a 1000 ml reaction flask,Add 600 ml of butanol,100 g of 2-amino-N- (2-chloropyridyl-3-yl) benzamide,2 ml of concentrated sulfuric acid,The reaction was refluxed for 3 hours at a reaction temperature of 80 C,Cooled to room temperature,filter,Washed with acetone,50-60 C in vacuo to give 98 g of a pale yellow solid product,Yield 98percent, purity 99percent.
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