Differentiation between [1, 2, 4] triazolo [1, 5??a] pyrimidine and [1, 2, 4] triazolo [4, 3??a]??pyrimidine regioisomers by 1H 15N HMBC experiments

…, AM García Collazo, P Pevarello

Index: Salgado, Antonio; Varela, Carmen; Collazo, Ana Maria Garcia; Pevarello, Paolo Magnetic Resonance in Chemistry, 2010 , vol. 48, # 8 p. 614 - 622

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Citation Number: 13

Abstract

Abstract The condensation of malonoaldehyde derivatives with either a 3-amino-[1, 2, 4]- triazole or a 3, 5-diamino-[1, 2, 4]-triazole precursor was studied. In agreement with previous reports, two different bicycles, namely, bearing the regioisomeric [1, 2, 4] triazolo [1, 5-a] pyrimidine (1) or [1, 2, 4] triazolo [4, 3-a] pyrimidine (2) structural surrogates, could be obtained. We found that, depending on the triazole precursor, only one regioisomer ...