Design, Synthesis, and Structure–Activity Relationships of a Novel Series of 5-Alkylidenepyridazin-3(2<i>H</i>)-ones with a Non-cAMP-Based Antiplatelet Activity
作者:Alberto Coelho、Enrique Raviña、Nuria Fraiz、Matilde Yáñez、Reyes Laguna、Ernesto Cano、Eddy Sotelo
DOI:10.1021/jm061401d
日期:2007.12.27
5-Alkylidenepyridazin-3-ones with four points of diversity (R-2, R-6, X, Y) have been synthesized and evaluated as platelet aggregation inhibitors. Several derivatives eliciting antiplatelet activity in the low micromolar range (e.g., 14e, 14k, 14p, 14v, IC50 congruent to 1 mu M) were identified. Structure-activity relationships studies on these compounds revealed the key molecular determinants of this new family of antiplatelet agents: (a) two ester groups in the alkoxy moieties; (b) lipophilic substituents at the N2 position of the pyridazin-3-one. The preliminary results of a pharmacological study aimed at determining the mechanism of action of a set of representative compounds revealed that, unlike other pyridazinones, the documented antiplatelet effect is not a consequence of a PDE-III inhibitory activity.