Structure-based drug design of pyrrolidine-1, 2-dicarboxamides as a novel series of orally bioavailable factor Xa inhibitors.

A novel series of pyrrolidine-1,2-dicarboxamides was discovered as factor Xa inhibitors using structure-based drug design. This series consisted of a neutral 4-chlorophenylurea P1, a biphenylsulfonamide P4 and a D-proline scaffold (1, IC(50) = 18 nM). Optimization of the initial hit resulted in an orally bioavailable, subnanomolar inhibitor of factor Xa (13, IC(50) = 0.38 nM), which was shown to be efficacious in a canine electrolytic model of thrombosis with minimal bleeding.

The discovery of (2R,4R)-N-(4-chlorophenyl)-N- (2-fluoro-4-(2-oxopyridin-1(2H)-yl)phenyl)-4-methoxypyrrolidine-1,2-dicarboxamide (PD 0348292), an orally efficacious factor Xa inhibitor.

Herein, we report the discovery of novel, proline-based factor Xa inhibitors containing a neutral P1 chlorophenyl pharmacophore. Through the additional incorporation of 1-(4-amino-3-fluoro-phenyl)-1H-pyridin-2-one 22, as a P4 pharmacophore, we discovered compound 7 (PD 0348292). This compound is a selective, orally bioavailable, efficacious FXa inhibitor that is currently in phase II clinical trials for the treatment and prevention of thrombotic disorders.

The discovery of glycine and related amino acid-based factor Xa inhibitors.

Herein, we report on the identification of three potent glycine and related amino acid-based series of FXa inhibitors containing a neutral P1 chlorophenyl pharmacophore. A X-ray crystal structure has shown that constrained glycine derivatives with optimized N-substitution can greatly increase hydrophobic interactions in the FXa active site. Also, the substitution of a pyridone ring for a phenylsulfone ring in the P4 sidechain resulted in an inhibitor with enhanced oral bioavailability.

Benzyl ether structure-activity relationships in a series of ketopiperazine-based renin inhibitors.

Inhibition of renin enzymatic activity by a series of ketopiperazine-based compounds containing a C6 benzyloxymethyl substituent correlated with a +(pi+sigma) effect. A 3-pyridinyloxymethyl substituent was also found to be equipotent as higher molecular weight analogs, and exhibited decreased CYP3A4 inhibition levels and improved pharmacokinetic properties.

Equipotent activity in both enantiomers of a series of ketopiperazine-based renin inhibitors.

We have found that both enantiomeric configurations of the 6-alkoxymethyl-1-aryl-2-piperazinone scaffold display equipotent renin inhibition activity and similar SAR patterns. This enantiomeric flexibility is in contrast to a previously reported 3-alkoxymethyl-4-arylpiperidine scaffold.

Discovery of novel non-peptidic ketopiperazine-based renin inhibitors.

Ketopiperazine 2 was designed from a previously published analog. Compound 2 was shown to be a novel, potent inhibitor of renin that, when administered orally, lowered blood pressure in a hypertensive double transgenic (human renin and angiotensinogen) mouse model. Compound 2 was further optimized to sub-nanomolar potency by designing an analog that addressed the S3 sub-pocket of the renin enzyme (16).