Pyrazoles, 1,5-diamino-, condensation with

Condensation of the 3,5-diamino-substituted pyrazole 303 with the dioxopyrrolidine ester 304 leads to formation of the central pyrimidine ring of 305 in good yield (Equation 82) <2002JCCS1051>. 

The same group has also prepared 26-membered polyazamacrocycles (298 X = 0, NH), by condensation of l//-pyrazole-3,5-dicarbaldehyde with l,5-diamino-3-oxapentane and diethylene-triamine followed by hydrogenation of the resulting Schiff bases (295 X = 0, NH) <93TL3159>. 

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