Pyrazolo acylamino

Acylation of 95 with acid anhydrides or acid chlorides gives the acylamino-pyrazoles 97, which cyclize into pyrazolo[3,4-t/]pyrimidines upon treatment with alkaline or acidic media. Intermediates 98 or 99 have been proposed (56JA784 59JA2452). The acetylpyrazole 97 (R = R = H, R = CH3) is... 

Fusion of the acylamino precursors 64 resulted in the intramolecular amidation with the C=N bond formation, affording the new ring system, ll/7-pyrazolo[3,4-2][l,6]benzodiazocin-ll-ones 65, (Equation 9) <2004ARK44>. 

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