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Design and synthesis of two pyrazole libraries based on o-hydroxyacetophenones

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Abstract

Two new solid-phase syntheses of substituted pyrazoles are described. The first includes supporting an o-hydroxyacetophenone on Merrifield resin, Vilsmeier-Haack formylation on the methyl group and cyclization with a substituted hydrazine to afford a pyrazole ring with two diversity centers. The second starts from o-hydroxyacetophenone supported on Wang resin, which undergoes a Claisen condensation with a carboxylic acid ester to yield a 1,3-dicarbonyl compound that cyclizes to a pyrazole using a hydrazine. Both methods have been used to synthesize two small pyrazole libraries.

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Author notes

  1. Enrique L. Michelotti

    Present address: Locus Discovery, Inc. Four Valley Square, 512 Township Line Rd., Blue Bell, PA, 19422, U.S.A

Authors and Affiliations

  1. Grup d'Enginyeria Molecular, Institut Químic de Sarrià, Universitat Ramon Llull, Via Augusta 390, E-08017, Barcelona, Spain

    José I. Borrell, Elisabeth Schuler & Jordi Teixidó

  2. Rohm and Haas Company, 727 Norristown Road, Spring House, Pennsylvania, 19477-0904, U.S.A.

    Enrique L. Michelotti

Authors
  1. José I. Borrell
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  2. Elisabeth Schuler
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  3. Jordi Teixidó
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  4. Enrique L. Michelotti
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Correspondence to José I. Borrell.

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Borrell, J.I., Schuler, E., Teixidó, J. et al. Design and synthesis of two pyrazole libraries based on o-hydroxyacetophenones. Mol Divers 8, 147–157 (2004). https://doi.org/10.1023/B:MODI.0000025629.45332.77

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  • DOI: https://doi.org/10.1023/B:MODI.0000025629.45332.77

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