Design, synthesis and biological evaluation of 6-chloro-quinolin-2-one derivatives as novel FXIa inhibitors.

A series of 6-chloro-quinolin-2-one derivatives were designed and synthesized as FXIa inhibitors by exploration of P1, P1 prime and P2 prime groups. Each compound was accessed for inhibitory effect on FXIa and some of them were evaluated in the clotting assay. 14c demonstrated excellent in-vitro potency (FXIa IC50: 15 nM, 2 x aPTT: 6.8 µM) and good in-vivo efficacy (prolonged in-vivo aPTT by more than 1-fold but not PT). Moreover, the pharmacokinetics property of 14c were evaluated following intravenous administration in rats, which indicated that 14c probably will be a clinical candidate for intravenous administration.

Fragment-Based Lead Generation of 5-Phenyl-1H-pyrazole-3-carboxamide Derivatives as Leads for Potent Factor Xia Inhibitors.

FXIa is suggested as a major target for anticoagulant drug discovery because of reduced risk of bleeding. In this paper, we defined 5-phenyl-1H-pyrazole-3-carboxylic acid derivatives as privileged fragments for FXIa inhibitors' lead discovery. After replacing the (E)-3-(5-chloro-2-(1H-tetrazol-1-yl)phenyl)acrylamide moiety in compound 3 with 5-(3-chlorophenyl)-1H-pyrazole-3-carboxamide, we traveled from FXIa inhibitor 3 to a scaffold that fused the privileged fragments into a pharmacophore for FXIa inhibitors. Subsequently, we synthesized and assessed the FXIa inhibitory potency of a series of 5-phenyl-1H-pyrazole-3-carboxamide derivatives with different P1, P1' and P2'moiety. Finally, the SAR of them was systematically investigated to afford the lead compound 7za (FXIa Ki = 90.37 nM, 1.5× aPTT in rabbit plasma = 43.33 µM) which exhibited good in vitro inhibitory potency against FXIa and excellent in vitro coagulation activities. Furthermore, the binding mode of 7za with FXIa was studied and the results suggest that the 2-methylcyclopropanecarboxamide group of 7za makes 2 direct hydrogen bonds with Tyr58B and Thr35 in the FXIa backbone, making 7za binds to FXIa in a highly efficient manner.

Synthesis of a Novel Series of Amino Acid Prodrugs Based on Thienopyridine Scaffolds and Evaluation of Their Antiplatelet Activity.

The thienopyridines class of drugs used as P2Y12 receptor antagonists plays a vital role in antiplatelet therapy. To further optimized this compound class, we designed and synthesized a series of amino acid prodrugs of 2-hydroxytetrahydrothienopyridine. All compounds were then evaluated for their inhibitory effect on ADP-induced platelet aggregation in rats and then ED50 and bleeding time of the most potent compounds were compared with commercial drugs. The results showed compound 5c could be a potent and safe candidate for further research.

Variant fatty acid-like molecules Conjugation, novel approaches for extending the stability of therapeutic peptides.

The multiple physiological properties of glucagon-like peptide-1 (GLP-1) make it a promising drug candidate for the treatment of type 2 diabetes. However, the in vivo half-life of GLP-1 is short due to rapid degradation by dipeptidyl peptidase-IV (DPP-IV) and renal clearance. The poor stability of GLP-1 has significantly limited its clinical utility; however, many studies are focused on extending its stability. Fatty acid conjugation is a traditional approach for extending the stability of therapeutic peptides because of the high binding affinity of human serum albumin for fatty acids. However, the conjugate requires a complex synthetic approach, usually involving Lys and occasionally involving a linker. In the current study, we conjugated the GLP-1 molecule with fatty acid derivatives to simplify the synthesis steps. Human serum albumin binding assays indicated that the retained carboxyl groups of the fatty acids helped maintain a tight affinity to HSA. The conjugation of fatty acid-like molecules improved the stability and increased the binding affinity of GLP-1 to HSA. The use of fatty acid-like molecules as conjugating components allowed variant conjugation positions and freed carboxyl groups for other potential uses. This may be a novel, long-acting strategy for the development of therapeutic peptides.

Discovery of 6-deoxydapagliflozin as a highly potent sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor for the treatment of type 2 diabetes.

Systematic mono-deoxylation of the four hydroxyl groups in the glucose moiety in dapagliflozin led to the discovery of 6-deoxydapagliflozin 1 as a more active sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor (IC50 = 0.67 nM against human SGLT2 (hSGLT2) vs 1.16 nM for dapagliflozin). It exhibited more potent blood glucose inhibitory activity in rat oral glucose tolerance test and induced more urinary glucose in rat urinary glucose excretion test than its parent compound dapagliflozin.