1: N,N-dimethyl-formamide With trichlorophosphate T=0°C; 1.5 h; 2: ethyl methyl ketone semicarbazone T=0 - 70°C; 3: With sodium hydroxide in water Cooling with ice;
参考文献
PFIZER, INC.
Patent: WO2009/144554 A1, 2009 ;
Location in patent: Page/Page column 38-39 ;