[C:1]([O:6][CH3:7])(=[O:5])[C:2]([O-])=O.C[O-:9].[Na+].[CH3:11][N:12]([CH:14]=[N:15][CH:16]=[N+](C)C)C.[Cl-]>C(COC)OC>[OH:9][C:16]1[C:2]([C:1]([O:6][CH3:7])=[O:5])=[CH:11][N:12]=[CH:14][N:15]=1Methyl oxalate (0.2 eq.) and malonomonoamide monomethyl ester (58.55 g, 0.50 mol) were added to an initial charge of sodium methoxide (279.4 g, 1.5 mol, 29% in methanol). 350 ml of dimethoxyethane were added. The solid Gold's reagent prepared as in Example 1 (89.35 g, 0.55 mol) was then added using a spatula. The suspension was then stirred at room temperature for 18 hours. The yellow suspension was poured on to an aqueous, ice-cold hydrochloric acid solution (2 eq. of HCl). Following filtration at pH 9-10, the moist sodium salt of the title product was taken up in HCl-saturated methanol, stirred for 15 min, filtered and dried. The yield of the title product in the form of its hydrochloride was 52.3 g (55%).
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