Tricyclic fused pyrazoles with a 'Click' 1,2,3-triazole substituent in position 3 are nanomolar CB1 receptor ligands

Chiara Zanato, Maria Grazia Cascio, Paolo Lazzari*, Roger Pertwee, Andrea Testa, Matteo Zanda

*Corresponding author for this work

Research output: Contribution to journalArticle

6 Citations (Scopus)
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Structural modification of the potent conformationally constrained tricyclic pyrazole CB1 ligand NESS0327 was achieved by replacing: (1) the chlorine substituent on the tricycle with a 3-fluoropropyl chain, and (2) the pyrazole 3-{[(piperidino)amino]carbonyl} substituent with a 4-substituted 1,2,3-triazole group obtained by click chemistry from an alkynyl precursor. Among the resulting compounds, two are particularly promising candidates for [18F]radiolabelling and PET imaging studies of the CB1 receptor, as they displayed K i CB1 = 62.5 nM and 42.5 nM, respectively, in the same range as that displayed by rimonabant.

Original languageEnglish
Pages (from-to)817-826
Number of pages10
Issue number6
Early online date16 Jan 2015
Publication statusPublished - Mar 2015



  • cannabinoids
  • click chemistry
  • fluorine
  • PET imaging
  • Sonogashira reaction

ASJC Scopus subject areas

  • Organic Chemistry
  • Catalysis

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