Browsing by Author "Quiroga Pueyo, Jairo"

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    An efficient two-step synthesis of novel 2-amino-substituted pyrazolo[1,5-a][1,3,5] triazines
    (2012) Insuasty Insuasty, Henry Edgardo; Insuasty Obando, Braulio Argiro; Castro, Edison; Quiroga Pueyo, Jairo; Abonia González, Rodrigo
    A series of novel 2-amino-substituted pyrazolo[1,5-a][1,3,5]triazines were selectively synthesized by a two-step reaction between 5-amino-3-hetaryl-1H-pyrazoles and hetaroyl isothiocyanates with subsequent amination and cyclization promoted by the couple HgCl2/TEA and DMF as solvent. This approach provided the title compounds in good to excellent yields and under mild reaction conditions. The structures of the new compounds were unambiguously established by spectroscopic and analytical techniques.
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    Publication
    Síntesis de nuevas pirazolo[1,5-a]-1,3,5-triazinas sustituidas con fragmentos amino y anillos heterocíclicos de reconocida bioactividad, en condiciones libre de disolvente, empleando irradiación con microondas
    (2012) Insuasty Insuasty, Henry Edgardo; Insuasty Obando, Braulio Argiro; Quiroga Pueyo, Jairo; Abonia González, Rodrigo; Mier Portilla, Nancy Paola
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    Three practical approaches for the synthesis of novel 4,7-dihetarylpyrazolo[1,5-a] [1,3,5] triazines
    (2012) Insuasty Insuasty, Henry Edgardo; Insuasty Obando, Braulio Argiro; Castro, Edison; Quiroga Pueyo, Jairo; Abonia González, Rodrigo; Nogueras, Manuel; Cobo, Justo
    Novel 4,7-dihetarylpyrazolo[1,5-a][1,3,5]triazines were synthesized from three different approaches. The first one, involved a one-step reaction between 5-amino-3-hetaryl-1H-pyrazoles and O,S-diethyl hetaroylimidothiocarbonates or S,S-diethyl hetaroylimidodithiocarbonates under solvent-free conditions employing microwave irradiation as the energy source. In the second approach, conventional heating under reflux in DMF as solvent was used instead of the microwave irradiation; and the third one was achieved from a two-step sequence through the treatment of 5-amino-3-hetaryl-1H-pyrazoles with hetaroyl isothiocyanates and the subsequent S-alkylation and cyclization process in DMF as solvent. Some intermediates were isolated and characterized to support the regiochemistry of the studied reactions. The structures of the new compounds were unambiguously established by spectroscopic and analytical techniques.