Design, synthesis and biological evaluation of (2S,3R,4R,5S,6R)-5-fluoro-6-(hydroxymethyl)-2-aryltetrahydro-2H-pyran-3,4-diols as potent and orally active SGLT dual inhibitors.

A new series of (2S,3R,4R,5S,6R)-5-fluoro-6-(hydroxymethyl)-2-aryltetrahydro-2H-pyran-3,4-diols as dual inhibitors of sodium glucose co-transporter proteins (SGLTs) were disclosed. Two methods were developed to efficiently synthesize C5-fluoro-lactones 3 and 4, which are key intermediates to the C5-fluoro-hexose based C-aryl glucosides. Compound 2b demonstrated potent hSGLT1 and hSGLT2 inhibition (IC50 = 43 nM for SGLT1 and IC50 = 9 nM for SGLT2). It showed robust inhibition of blood glucose excursion in oral glucose tolerance test (OGTT) in Sprague Dawley (SD) rats and exerted pronounced antihyperglycemic effects in db/db mice and high-fat diet-fed ZDF rats when dosed orally at 10 mg/kg.

Synthesis and biological evaluation of benzocyclobutane-C-glycosides as potent and orally active SGLT1/SGLT2 dual inhibitors.

Synthesis and biological evaluation of benzocyclobutane-C-glycosides as potent and orally active SGLT1/SGLT2 dual inhibitors are described. Compound 19 showed high inhibitory potency at SGLT1 (IC50 = 45 nM), and excellent potency at SGLT2 (IC50 = 1 nM). It also displayed excellent PK profiles in mice, rats, dogs and monkeys (F = 78-107%). In SD rats, compound 19 treatments significantly reduced blood glucose levels in a dose-dependent manner. In ZDF rats, compound 19 displayed anti-hyperglycemic effect up to 24 h. Therefore, compound 19 may serve as valuable pharmacological tool, and potential use as a treatment for metabolic syndrome.

Substituted thieno[2,3-d]pyrimidines as adenosine A2A receptor antagonists.

A novel series of benzyl substituted thieno[2,3-d]pyrimidines were identified as potent A2A receptor antagonists. Several five- and six-membered heterocyclic replacements for the optimized methylfuran were explored. Select compounds effectively reverse catalepsy in mice when dosed orally.

Optimization of arylindenopyrimidines as potent adenosine A(2A)/A(1) antagonists.

Two reactive metabolites were identified in vivo for the dual A(2A)/A(1) receptor antagonist 1. Two strategies were implemented to successfully mitigate the metabolic liabilities associated with 1. Optimization of the arylindenopyrimidines led to a number of amide, ether, and amino analogs having comparable in vitro and in vivo activity.

Synthesis and biological evaluation of novel pyridazinone-based alpha4 integrin receptor antagonists.

A novel series of pyridazinone-functionalized phenylalanine analogues was prepared and evaluated for inhibition of cellular adhesion mediated by alpha4beta1/VCAM-1 and alpha4beta7/MAdCAM-1 interactions. Concise syntheses were developed and applied for exploration of structure-activity relationships pertaining to the pyridazinone ring as well as the N-acyl phenylalanine scaffold. Potent dual antagonists of alpha4beta1 and alpha4beta7 were generated from an amide subseries; antagonists selective for alpha4beta7 were identified from urea and carbamate-based subseries. The pharmacokinetic properties of selected members of the series have been determined in rats and demonstrate that the use of ester prodrugs and alterations to the amide linkage can lead to improved oral bioavailability in this series. An alpha4beta7-selective member of the carbamate subseries (36c), upon oral administration, demonstrated in vivo efficacy in the mouse DSS colitis model.

Rationale, design, and synthesis of novel phenyl imidazoles as opioid receptor agonists for gastrointestinal disorders.

A small series of novel, imidazoles 4 have been prepared that exhibit very good binding affinities for the delta and mu opioid receptors (ORs), as well as demonstrate potent agonist functional activity at the delta OR. Representative imidazole 4a (K(i) delta = 0.9 nM; K(i) mu = 55 nM; K(i) kappa = 124 nM; EC(50) delta =13-25 nM) was further profiled for OR related in vivo effects. Compound 4a reduced gastrointestinal (GI) propulsive motility in a dose-dependent and naloxone-reversible manner, based on the results of the mouse glass bead expulsion test (3, 5, and 10 mg/kg, ip) and the mouse fecal pellet output test (1 and 3 mg/kg, ip). Compound 4a showed no analgesic activity as measured by the mouse abdominal irritant test (MAIT) when dosed at 100 mg/kg, sc, but did show significant MAIT activity at doses of both 10 microg (40% inhibition) and 100 microg (100% inhibition) when dosed intracerebroventricularly (icv). Taken together, these in vivo results suggest that 4a acts peripherally when dosed systemically, and that these prototypical compounds may prove promising as medicinal leads for GI indications.

Design and characterization of optimized adenosine A2A/A1 receptor antagonists for the treatment of Parkinson's disease.

The design and characterization of two, dual adenosine A(2A)/A(1) receptor antagonists in several animal models of Parkinson's disease is described. Compound 1 was previously reported as a potential treatment for Parkinson's disease. Further characterization of 1 revealed that it was metabolized to reactive intermediates that caused the genotoxicity of 1 in the Ames and mouse lymphoma L51784 assays. The identification of the metabolites enabled the preparation of two optimized compounds 13 and 14 that were devoid of the metabolic liabilities associated with 1. Compounds 13 and 14 are potent dual A(2A)/A(1) receptor antagonists that have excellent activity, after oral administration, across a number of animal models of Parkinson's disease including mouse and rat models of haloperidol-induced catalepsy, mouse and rat models of reserpine-induced akinesia, and the rat 6-hydroxydopamine (6-OHDA) lesion model of drug-induced rotation.

Small intestinal cannabinoid receptor changes following a single colonic insult with oil of mustard in mice.

Cannabinoids are known to be clinically beneficial for control of appetite disorders and nausea/vomiting, with emerging data that they can impact other GI disorders, such as inflammation. Post-inflammatory irritable bowel syndrome (PI-IBS) is a condition of perturbed intestinal function that occurs subsequent to earlier periods of intestinal inflammation. Cannabinoid 1 receptor (CB1R) and CB2R alterations in GI inflammation have been demonstrated in both animal models and clinically, but their continuing role in the post-inflammatory period has only been implicated to date. Therefore, to provide direct evidence for CBR involvement in altered GI functions in the absence of overt inflammation, we used a model of enhanced upper GI transit that persists for up to 4 weeks after a single insult by intracolonic 0.5% oil of mustard (OM) in mice. In mice administered OM, CB1R immunostaining in the myenteric plexus was reduced at day 7, when colonic inflammation is subsiding, and then increased at 28 days, compared to tissue from age-matched vehicle-treated mice. In the lamina propria CB2R immunostaining density was also increased at day 28. In mice tested 28 day after OM, either a CB1R-selective agonist, ACEA (1 and 3 mg/kg, s.c.) or a CB2R-selective agonist, JWH-133 (3 and 10 mg/kg, s.c.) reduced the enhanced small intestinal transit in a dose-related manner. Doses of ACEA and JWH-133 (1 mg/kg), alone or combined, reduced small intestinal transit of OM-treated mice to a greater extent than control mice. Thus, in this post-colonic inflammation model, both CBR subtypes are up-regulated and there is increased efficacy of both CB1R and CB2R agonists. We conclude that CBR remodeling occurs not only during GI inflammation but continues during the recovery phase. Thus, either CB1R- or CB2-selective agonists could be efficacious for modulating GI motility in individuals experiencing diarrhea-predominant PI-IBS.

Agonists of cannabinoid receptor 1 and 2 inhibit experimental colitis induced by oil of mustard and by dextran sulfate sodium.

Oil of mustard (OM) is a potent neuronal activator that is known to elicit visceral hyperalgesia when given intracolonically, but the full extent to which OM is also proinflammatory in the gastrointestinal tract is not known. We have previously shown that male CD-1 mice given a single administration of 0.5% OM develop a severe colitis that is maximum at day 3 and that gradually lessens until essentially absent by day 14. OM-induced neuronal stimulation is reported to be reduced by cannabinoid agonists, and cannabinoid receptor 1 (CB1R)-/- mice have exacerbated experimental colitis. Therefore, we examined the role of cannabinoids in this OM-induced 3-day model of colitis in CD-1 mice and in a 7-day dextran sulfate sodium (DSS) colitis model in BALB/c mice. In OM colitis, the CB1R-selective agonist ACEA and the CB2R-selective agonist JWH-133 reduced (P < 0.05) colon weight gain (means +/- SE; 82 +/- 13% and 47 +/- 15% inhibition, respectively), colon shrinkage (98 +/- 24% and 42 +/- 12%, respectively), colon inflammatory damage score (49 +/- 11% and 40 +/- 12%, respectively), and diarrhea (58 +/- 12% and 43 +/- 11%, respectively). Histological damage was similarly reduced by these treatments. Likewise, CBR agonists attenuated DSS colitis, albeit at higher doses; ACEA at 10 mg/kg, twice daily, inhibited (P < 0.05) macroscopic and microscopic scores (46 +/- 9% and 63 +/- 7%, respectively); whereas 20 mg/kg, twice daily, of JWH-133 was required to diminish (P < 0.05) macroscopic and microscopic scores (29 +/- 7% and 43 +/- 5%, respectively). CB1R and CB2R immunostaining of colon sections revealed that CB1R in enteric neurons was more intense in colitic vs. control mice; however, CB1R was also increased in the endothelial layer in OM colitis only. CB2R immunostaining was more marked in infiltrated immune cells in OM colitis. These findings validate the OM colitis model with respect to the DSS model and provide strong support to the emerging idea that cannabinoid receptor activation mediates protective mechanisms in experimental colitis. The demonstration of CB1R agonist effects in colitis support the neurogenic nature of the OM-induced colitis model and reinforce the importance of neuronal activation in intestinal inflammation.

Aza-bicyclic amino acid carboxamides as alpha4beta1/alpha4beta7 integrin receptor antagonists.

A series of N-carboxy, N-alkyl, and N-carboxamido azabicyclo[2.2.2]octane carboxamides were prepared and assayed for inhibition of alpha4beta1-VCAM-1 and alpha4beta7-MAdCAM-1 interactions. Potency and alpha4beta1/alpha4beta7 selectivity were sensitive to the substituent R1-R3 in the structures 6, 7, and 8. Several compounds demonstrated low nanomolar balanced alpha4beta1/alpha4beta7 in vitro activity. Two compounds were selected for in vivo leukocytosis studies and demonstrated increases in circulating lymphocytes up to 250% over control.