Biagini P, Biancalani C, Graziano A, Cesari N, Giovannoni MP, Cilibrizzi A, Dal Piaz V, Vergelli C, Crocetti L, Delcanale M, Armani E, Rizzi A, Puccini P, Gallo PM, Spinabelli D, Caruso P. Functionalized pyrazoles and pyrazolo[3,4-d]pyridazinones: Synthesis and evaluation of their phosphodiesterase 4 inhibitory activity.
Bioorg Med Chem 2010;
18:3506-17. [PMID:
20413313 DOI:
10.1016/j.bmc.2010.03.066]
[Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 03/23/2010] [Accepted: 03/25/2010] [Indexed: 11/29/2022]
Abstract
A series of pyrazoles and pyrazolo[3,4-d]pyridazinones were synthesized and evaluated for their PDE4 inhibitory activity. All the pyrazoles were found devoid of activity, whereas some of the novel pyrazolo[3,4-d]pyridazinones showed good activity as PDE4 inhibitors. The most potent compounds in this series showed an IC(50) in the nanomolar range. The ability to inhibit TNF-alpha release in human PBMCs was determined for two representative compounds, finding values in the sub-micromolar range. SARs studies demonstrated that the best arranged groups around the heterocyclic core are 2-chloro-, 2-methyl- and 3-nitrophenyl at position 2, an ethyl ester at position 4 and a small alkyl group at position 6. Molecular modeling studies performed on a representative compound allowed to define its binding mode to the PDE4B isoform.
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