Piperazinyl Glutamate Pyridines as Potent Orally Bioavailable P2Y12 Antagonists for Inhibition of Platelet Aggregation

Polymer-assisted solution-phase (PASP) parallel library synthesis was used to discover a piperazinyl glutamate pyridine as a P2Y12 antagonist. Exploitation of this lead provided compounds with excellent inhibition of platelet aggregation as measured in a human platelet rich plasma (PRP) assay. Pharmacokinetic and physiochemical properties were optimized through modifications at the 4-position of the pyridine ring and the terminal nitrogen of the piperazine ring, leading to compound (4S)-4-[({4-[4-(methoxymethyl)piperidin-1-yl]-6-phenylpyridin-2-yl}carbonyl)amino]-5-oxo-5-{4-[(pentyloxy)carbonyl]piperazin-1-yl}pentanoic acid 47s with good human PRP potency, selectivity, in vivo efficacy, and oral bioavailability. Compound 47s was selected for further preclinical evaluations.