Original Functionalized Pyrazoles For Drug Discovery

Pyrazole fragment is found in many low-molecular weight compounds possessing a wide range of biological activities and materials science related properties.¹ Currently there are 14 pyrazole-based marketed drugs in which the 1-arylpyrazole motif is mainly present, e.g., as in Sulfaphenazole 1 shown in Figure 1.² Substituted pyrazoles have also found agricultural uses as insecticides and herbicides. For example, Fipronil^® 2 depicted in Fig. 1 is one of the most commercially successful insecticides. Notably, the first pyrazole-containing naturally occurring acids (1H-pyrazole-3-carboxylic acid and 4-methyl-1H-pyrazole-3-carboxylic acid) were recently isolated from a marine sponge.³ This is expected to stimulate further biological studies of functionalized pyrazoles.

Other important applications of pyrazoles include supramolecular chemistry (e.g., compound 3 that is a polyamine receptor able to complex l-glutamate in water at physiological pH values⁴), polymer chemistry, and the food industry. Substituted pyrazoles have also been applied as ligands for transition metal-catalyzed reactions.⁵ For instance, Pd-complexes of ligand 4 were shown to efficiently catalyze amination reactions of a broad range of aryl halides.⁶In industry some pyrazole derivatives immobilized on silica gel were used for the recovery of heavy metal ions from aqueous solutions.⁷

Figure 1. Examples of applications of pyrazole-containing compounds.

Presented below are a set of functionalized pyrazoles that are perfectly suited for the use in drug discovery and organic synthesis. The complete set of the title structures available from Life Chemicals will be provided upon request at orders@lifechemicals.com.

References:

1. Yet, L. in Comprehensive Heterocyclic Chemistry, 3rd edition, eds. A.R. Katritzky, C.A. Ramsden, E.F.V. Scriven, and R. J.K. Taylor Pergamon, Oxford, 2008. Vol. 4, p. 1.
2. www.drugbank.ca; accessed in June 2019.
3. Parameswaran, P.S.; Naik, C.G.; Hegde, V.R. J. Nat. Prod., 1997, 60, 802.
4. Miranda, C.; Escartí, F.; Lamarque, L.; Yunta, M.J.R.; Navarro, P.; García-España, E.; Jimeno, M.L. J. Am. Chem. Soc. 2004, 126, 823.
5. Ojwach, S. O.; Darkwa, J. Inorg. Chim. Acta 2011, 363, 1947
6. Singer, R.A.; Caron, S.; McDermott, R.E.; Arpin, R.; Do, N.M. Synthesis 2003, 1727.
7. Radi, S.; Ramdani, A.; Lekchiri, Y.; Morcellet, M.; Crini, G.; Janusc, L.; Bacquet, M. New J. Chem. 2003, 27, 1224.