ABSTRACT
A novel series of nonsteroidal mineralocorticoid receptor (MR) antagonists identified as part of our strategy to follow up on the clinical candidate PF-03882845 (2) is reported. Optimization departed from the previously described pyrazoline 3a and focused on improving the selectivity for MR versus the progesterone receptor (PR) as an approach to avoid potential sex-hormone-related adverse effects and improving biopharmaceutical properties. From this effort, (R)-14c was identified as a potent nonsteroidal MR antagonist (IC50 = 4.5 nM) with higher than 500-fold selectivity versus PR and other related nuclear hormone receptors, with improved solubility as compared to 2 and pharmacokinetic properties suitable for oral administration. (R)-14c was evaluated in vivo using the increase of urinary Na(+)/K(+) ratio in rat as a mechanism biomarker of MR antagonism. Treatment with (R)-14c by oral administration resulted in significant increases in urinary Na(+)/K(+) ratio and demonstrated this novel compound acts as an MR antagonist.
Subject(s)
Mineralocorticoid Receptor Antagonists/chemical synthesis , Nicotinic Acids/chemical synthesis , Pyrazoles/chemical synthesis , Animals , Drug Discovery , Male , Mineralocorticoid Receptor Antagonists/pharmacology , Molecular Docking Simulation , Nicotinic Acids/pharmacology , Potassium/urine , Pyrazoles/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, Mineralocorticoid/chemistry , Sodium/urine , Structure-Activity RelationshipABSTRACT
A series of GPR119 agonists based on a 2,6-diazatricyclo[3.3.1.1â¼3,7â¼]decane ring system is described. Also provided is a detailed account of the development of a multigram scale synthesis of the diazatricyclic ring system, which was achieved using a Hofmann-Löffler-Freytag reaction as the key step. The basis for the use of this complex framework lies in an attempt to constrain one end of the molecule in the "agonist conformation" as was previously described for 3-oxa-7-aza-bicyclo[3.3.1]nonanes. Optimization of carbamate analogues of the diazatricylic compounds led to the identification of 32i as a potent agonist of the GPR119 receptor with low unbound human liver microsomal clearance. The use of an agonist response weighted ligand lipophilic efficiency (LLE) termed AgLLE is discussed along with the issues of applying efficiency measures to agonist programs. Ultimately, solubility limited absorption and poor exposure reduced further interest in these molecules.
Subject(s)
Aza Compounds/chemical synthesis , Bridged-Ring Compounds/chemical synthesis , Cyclodecanes/chemical synthesis , Receptors, G-Protein-Coupled/agonists , Animals , Aza Compounds/chemistry , Aza Compounds/pharmacology , Biological Availability , Bridged-Ring Compounds/chemistry , Bridged-Ring Compounds/pharmacology , Crystallography, X-Ray , Cyclodecanes/chemistry , Cyclodecanes/pharmacology , Dogs , Drug Design , Humans , Male , Microsomes, Liver/metabolism , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Pyrimidines/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, G-Protein-Coupled/chemistry , Solubility , Stereoisomerism , Structure-Activity RelationshipABSTRACT
A novel GPR119 agonist based on the 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole scaffold was designed through lead optimization starting from pyrazole-based GPR119 agonist 1. The design is centered on the conformational restriction of the core scaffold, while minimizing the change in spatial relationships of two key pharmacophoric elements (piperidine-carbamate and aryl sulfone).
Subject(s)
Pyrazoles/chemistry , Receptors, G-Protein-Coupled/agonists , Carbamates/chemistry , Humans , Piperidines/chemistry , Protein Binding , Pyrazoles/chemical synthesis , Pyrazoles/metabolism , Receptors, G-Protein-Coupled/metabolism , Structure-Activity RelationshipABSTRACT
We report the design and synthesis of a series of 6-(2,4-diaminopyrimidinyl)-1,4-benzoxazin-3-ones as orally bioavailable small molecule inhibitors of renin. Compounds with a 2-methyl-2-aryl substitution pattern exhibit potent renin inhibition and good permeability, solubility, and metabolic stability. Oral bioavailability was found to be dependent on metabolic clearance and cellular permeability, and was optimized through modulation of the sidechain that binds in the S3(sp) subsite.
Subject(s)
Benzoxazines/chemistry , Benzoxazines/pharmacology , Drug Design , Pyridines/chemistry , Renin/antagonists & inhibitors , Amination , Animals , Benzoxazines/chemical synthesis , Benzoxazines/metabolism , Crystallography, X-Ray , Male , Models, Molecular , Molecular Structure , Rats , Rats, Sprague-Dawley , Renin/chemistry , Renin/metabolism , Structure-Activity RelationshipABSTRACT
Novel 2,4-diaminopyrimidine-based small molecule renin inhibitors are disclosed. Through high throughput screening, parallel synthesis, X-ray crystallography, and structure based drug design, we have developed the first non-chiral, non-peptidic, small molecular template to possess moderate potency against renin. The designed compounds consist of a novel 6-ethyl-5-(1,2,3,4-tetrahydroquinolin-7-yl)pyrimidine-2,4-diamine ring system that exhibit moderate potency (IC(50): 91-650 nM) against renin while remaining 'Rule-of-five' compliant.
Subject(s)
Chemistry, Pharmaceutical/methods , Pyrimidines/chemistry , Renin/antagonists & inhibitors , Animals , Crystallography, X-Ray , Drug Design , Inhibitory Concentration 50 , Models, Chemical , Models, Molecular , Molecular Conformation , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Rats , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
A systematic investigation of the S3 sub-pocket activity requirements was conducted. It was observed that linear and sterically small side chain substituents are preferred in the S3 sub-pocket for optimal renin inhibition. Polar groups in the S3-sub-pocket were not well tolerated and caused a reduction in renin inhibitory activity. Further, compounds with clog P's < or = 3 demonstrated a dramatic reduction in CYP3A4 inhibitory activity.
Subject(s)
Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Piperazines/chemistry , Piperazines/pharmacology , Renin/antagonists & inhibitors , Crystallography, X-Ray , Cytochrome P-450 CYP3A , Cytochrome P-450 Enzyme System/drug effects , Enzyme Inhibitors/chemical synthesis , Humans , Models, Molecular , Molecular Structure , Piperazines/chemical synthesis , Stereoisomerism , Structure-Activity RelationshipABSTRACT
The activated factor VII/tissue factor complex (FVIIa/TF) is known to play a key role in the formation of blood clots. Inhibition of this complex may lead to new antithrombotic drugs. A fluoropyridine-based series of FVIIa/TF inhibitors was discovered which utilized a diisopropylamino group for binding in the S2 and S3 binding pockets of the active site of the enzyme complex. In this series, an enhancement in binding affinity was observed by substitution at the 5-position of the hydroxybenzoic acid sidechain. An X-ray crystal structure indicates that amides at this position may increase inhibitor binding affinity through interactions with the S1'/S2' pocket.
Subject(s)
Enzyme Inhibitors/pharmacology , Factor VIIa/antagonists & inhibitors , Pyridines/pharmacology , Thromboplastin/antagonists & inhibitors , Crystallography, X-Ray , Drug Evaluation, Preclinical , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Models, Molecular , Molecular Structure , Pyridines/chemical synthesis , Pyridines/chemistry , Structure-Activity RelationshipABSTRACT
The activated Factor VII/tissue factor complex (FVIIa/TF) plays a key role in the formation of blood clots. Inhibition of this complex may lead to new antithrombotic drugs. An X-ray crystal structure of a fluoropyridine-based FVIIa/TF inhibitor bound in the active site of the enzyme complex suggested that incorporation of substitution at the 5-position of the hydroxybenzoic acid side chain could lead to the formation of more potent inhibitors through interactions with the S1'/S2' pocket.
Subject(s)
Enzyme Inhibitors/chemical synthesis , Factor VIIa/chemistry , Fibrinolytic Agents/chemical synthesis , Pyridines/chemical synthesis , Thromboplastin/chemistry , Binding Sites , Crystallography, X-Ray , Enzyme Inhibitors/chemistry , Factor VIIa/antagonists & inhibitors , Factor Xa Inhibitors , Fibrinolytic Agents/chemistry , Fibrinolytic Agents/pharmacology , Humans , Inhibitory Concentration 50 , Protein Binding , Prothrombin Time , Pyridines/chemistry , Structure-Activity Relationship , Thromboplastin/antagonists & inhibitorsABSTRACT
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).
