Novel 5-aryl-1,3-dihydro-indole-2-thiones. potent,orally active progesterone receptor agonists

During the course of our studies on 3,3-disubstituted-5-aryloxindoles derived progesterone receptor (PR) antagonists we discovered that changing the amide funtionality to a thio-amide resulted in compounds displaying potent PR agonist activity. In this communication, the synthesis, structure activity relationships (SAR) and in vivo activity of various 5-arylthio-oxindoles will be discussed.     

Novel pyridine derivatives as potent and selective CB2 cannabinoid receptor agonists

Replacement of the phenyl ring in our previous (morpholinomethyl)aniline carboxamide cannabinoid receptor ligands with a pyridine ring led to the discovery of a novel chemical series of CB₂ ligands. Compound 3, that is, 2,2-dimethyl-N-(5-methyl-4-(morpholinomethyl)pyridin-2-yl)butanamide was identified as a potent and selective CB₂ agonist exhibiting in vivo efficacy after oral administration in a rat model of neuropathic pain.     

Discovery of orally active,pyrrolidinone-based progesterone receptor partial agonists

We have designed and synthesized a novel series of pyrrolidinones as progesterone receptor partial agonists. Compounds from this series had improved AR selectivity, rat pharmacokinetic properties, and in vivo potency compared to the lead compound. In addition, these compounds had improved selectivity against hERG channel inhibition.     

Discovery of potent, selective, orally active benzoxazepine-based Orexin-2 receptor antagonists

During our efforts to identify a series of potent, selective, orally active human Orexin-2 Receptor (OX2R) antagonists, we elucidated structure-activity relationship (SAR) on the 7-position of a benzoxazepine scaffold by utilizing Hammett σ(p) and Hansch-Fujita π value as aromatic substituent constants. The attempts led to the discovery of compound 1m, possessing good in vitro potency with over 100-fold selectivity against OX1R, good metabolic stability in human and rat liver microsome, good oral bioavailability in rats, and in vivo antagonistic activity in rats by oral administration.     

Discovery of potent and selective nonsteroidal indazolyl amide glucocorticoid receptor agonists

Modification of a phenolic lead structure based on lessons learned from increasing the potency of steroidal glucocorticoid agonists lead to the discovery of exceptionally potent, nonsteroidal, indazole GR agonists. SAR was developed to achieve good selectivity against other nuclear hormone receptors with the ultimate goal of achieving a dissociated GR agonist as measured by human in vitro assays. The specific interactions by which this class of compounds inhibits GR was elucidated by solving an X-ray co-crystal structure.     

Novel phenylamino acetamide derivatives as potent and selective kappa opioid receptor agonists

A novel series of phenylamino acetamide derivatives was synthesized. These amides were shown to be potent and selective kappa opioid receptor agonists.     

5-Substituted 4-anilinoquinazolines as potent, selective and orally active inhibitors of erbB2 receptor tyrosine kinase

Starting from a 6,7-substituted quinazoline lead 4, optimisation of 5-substituted quinazolines containing an extended aniline motif led to potent and selective inhibitors of erbB2 receptor tyrosine kinase, and a representative compound 12a inhibited tumour growth in a mouse xenograft model.     

Synthesis and biological evaluation of novel potent FFA1 agonists containing 2,3-dihydrobenzo[b][1,4]dioxine

FFA1 (free fatty acid receptor 1) has emerged as an attractive antidiabetic target due to its role in mediating the enhancement of glucose-stimulated insulin secretion in pancreatic β cells with a low risk of hypoglycemia. Many reported FFA1 agonists possessed somewhat pharmacokinetic and/or safety issues. Herein, we describe the identification of 2,3-dihydrobenzo[b][1,4]dioxine as a novel scaffold for FFA1 agonists. Comprehensive structure-activity relationship study based on this scaffold led to the discovery of (S)-3-(4-(((S)-7-(4-methoxyphenyl)-2,3-dihydrobenzo [b][1,4]dioxin-2-yl)methoxy) phenyl)hex-4-ynoic acid (26k), which displayed a potent FFA1 agonistic activity and good pharmacokinetic profiles. Subsequent in vivo studies demonstrated that compound 26k significantly improved the glucose tolerance in ICR mice. In summary, compound 26k is a promising drug candidate for further investigation.     

1-[2-[(Heteroarylmethoxy)aryl]carbamoyl]indolines are selective and orally active 5-HT2C receptor inverse agonists

Bisarylmethoxyethers have been identified with nanomolar 5-HT2C affinity and selectivity over both 5-HT2A and 5-HT2B receptors. Compounds such as 1, 2, 8, 12, 14 and 18 have potent oral activity in a centrally mediated pharmacodynamic model of 5-HT2C function and their therapeutic potential is currently under further investigation.     

Discovery of diphenylcarbamate derivatives as highly potent and selective IP receptor agonists: orally active prostacyclin mimetics. Part 3

The new classes of diphenylcarbamate derivatives with a tetrahydronaphthalene skeleton as highly potent and selective IP agonists have been discovered. The optimized diphenylcarbamate type compound FK-788: (R)-4 exhibited potent antiaggregative potency with an IC50 of 18 nM and high binding affinity for the human recombinant IP receptor with K(i) values of 20 nM and selectivity for human IP over all other members of the human prostanoid receptor family. Compound (R)-4 was shown to exhibit good pharmacokinetic properties in rats and dogs, and also good bioavailability in healthy volunteers.     

2-Piperazinecarboxamides as potent and selective melanocortin subtype-4 receptor agonists

We report the discovery and optimization of substituted 2-piperazinecarboxamides as potent and selective agonists of the melanocortin subtype-4 receptor. The 5- and 6-alkylated piperazine compounds exhibit low bioactivation potential as measured by covalent binding in microsome preparations.     

Pyridobenzodiazepines: a novel class of orally active, vasopressin V2 receptor selective agonists

Our efforts in seeking low molecular weight agonists of the antidiuretic peptide hormone arginine vasopressin (AVP) have led to the identification of the clinical candidate WAY-151932 (VNA-932). Further exploration of the structural requirements for agonist activity has provided another class of potent, orally active, non-peptidic vasopressin V2 receptor selective agonists exemplified by the 5,11-dihydro-pyrido[2,3-b][1,5]benzodiazepine as a candidate for further development.     

Novel 6-aminofuro[3,2-c]pyridines as potent,orally efficacious inhibitors of cMET and RON kinases

A series of novel 6-aminofuro[3,2-c]pyridines as kinase inhibitors is described, most notably, OSI-296 (6). We discuss our exploration of structure–activity relationships and optimization leading to OSI-296 and disclose its pharmacological activity against cMET and RON in cellular assays. OSI-296 is a potent and selective inhibitor of cMET and RON kinases that shows in vivo efficacy in tumor xenografts models upon oral dosing and is well tolerated.     

SAR study of 2,3,4,14b-tetrahydro-1H-dibenzo[b,f]pyrido[1,2-d][1,4]oxazepines as progesterone receptor agonists

We have developed a new class of progesterone receptor agonists having a tetracyclic dibenzo-oxazepine structure 1. In this paper, the synthesis and structure-activity relationships of this new class are described. This work led to the identification of potent progesterone agonists up to 1 nM activity. Substitution at positions 6, 7 and 1 has proven to be crucial for activity, indicating that probably these positions are involved in important interactions with the receptor.     

Sulfonamide derivatives as new potent and selective CB2 cannabinoid receptor agonists

A novel series of sulfonamide derivatives 3, the CB(2) receptor agonists, was synthesized and evaluated for activity against the human CB(2) receptor. We first identified sulfonamide 3a, which was obtained by random screening of our in-house chemical library as a moderately active (CB(2) IC(50)=340nM) CB(2) receptor agonist. We then attempted to test its analogues to identify compounds with a high affinity for the CB(2) receptor. One of these, compound 3f, exhibited high affinity for the human CB(2) receptor (IC(50)=16nM) and high selectivity for CB(2) over CB(1) (CB(1) IC(50)/CB(2)IC(50)=106), and behaved as a full CB(2) receptor agonist in the [(35)S]GTPgammaS binding assay (CB(2) EC(50)=7.2nM, E(max)=100%).     

Novel tricyclic pyrazolopyrimidines as potent and selective GPR119 agonists

Systematic SAR optimization of the GPR119 agonist lead 1, derived from an internal HTS campaign, led to compound 29. Compound 29 displays significantly improved in vitro activity and oral exposure, leading to GLP1 elevation in acutely dosed mice and reduced glucose excursion in an OGTT study in rats at doses ⩾10 mg/kg.     

Discovery of N-sulfonyl-7-azaindoline derivatives as potent,orally available and selective M4 muscarinic acetylcholine receptor agonists

We designed and synthesized novel N-sulfonyl-7-azaindoline derivatives as selective M₄ muscarinic acetylcholine receptor agonists. Modification of the N-carbethoxy piperidine moiety of compound 2, an M₄ muscarinic acetylcholine receptor (mAChR)-preferring agonist, led to compound 1, a selective M₄ mAChR agonist. Compound 1 showed a highly selective M₄ mAChR agonistic activity with weak hERG inhibition in vitro. A pharmacokinetic study of compound 1 in vivo revealed good bioavailability and brain penetration in rats. Compound 1 reversed methamphetamine-induced locomotor hyperactivity in rats (1–10 mg/kg, po).     

Design and synthesis of phenethyl benzo[1,4]oxazine-3-ones as potent inhibitors of PI3Kinasegamma

The Type 1 PI3Kinases comprise a family of enzymes, which primarily phosphorylate PIP2 to give the second messenger PIP3, a key player in many intracellular signaling processes [Science, 2002, 296, 1655; Trends Pharmacol. Sci.2003, 24, 366]. Of the four type 1 PI3Ks, the gamma-isoform, which is expressed almost exclusively in leukocytes [Curr. Biol., 1997, 7, R470], is of particular interest with respect to its role in inflammatory diseases such as rheumatoid arthritis (RA) and chronic obstructive pulmonary disease (COPD) [Mol. Med. Today, 2000, 6, 347]. Investigation of a series of 4,6-disubstituted-4H-benzo[1,4]oxazin-3-ones has led to the identification of single-digit nanomolar inhibitors of PI3Kgamma, several of which had good cell based activity and were shown to be active in vivo in an aspectic peritonitis model of inflammatory cell migration.