Ethyl 2-chloro-5-cyclopropyl-6- amino nicotinate

It was claimed that cyclization of ethyl 2-chloro-5-cyclopropyl-6- [(7V-(4,5-dimethoxy-2-nitrophenyl)methoxy)carbonyl]-A-(2-fluoro-3-hydroxy-l-oxo-2-propen-l-yl)amino nicotinate (321) in boiling aqueous dioxane in the presence of K2C03 overnight yielded l- [(4,5-dimethoxy-2-nitrophe-nyl)methoxy]carbonyl -9-cyclopropyl-3-fluoro-2-oxo-2,6-dihydropyrido[l, 2-u]pyrimidine-7-carboxylate (160) (95MIP1, 96MIP4, 96USP5580872). 

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