GPR40, one of the G protein-coupled receptors predominantly expressed in pancreatic β-cells, mediates enhancement of glucose-stimulated insulin secretion by free fatty acids. A potent and selective GPR40 agonist is theorized to be a safe and effective antidiabetic drug with little or no risk of hypoglycemia. Cyclization of the phenylpropanoic acid moiety of lead compound 1 produced fused phenylalkanoic acids with favorable in vitro agonist activities and pharmacokinetic profiles. Further optimization led to the discovery of dihydrobenzofuran derivative 9a ([(3S)-6-({2',6'-dimethyl-4'-[3-(methylsulfonyl)propoxy]biphenyl-3-yl}methoxy)-2,3-dihydro-1-benzofuran-3-yl]acetic acid hemi-hydrate, TAK-875) as a potent, selective, and orally bioavailable GPR40 agonist, with a pharmacokinetic profile enabling long-acting drug efficacy. Compound 9a showed potent plasma glucose-lowering action and insulinotropic action during an oral glucose tolerance test in female Wistar fatty rats with impaired glucose tolerance. Compound 9a is currently in clinical trials for the treatment of type 2 diabetes mellitus.

G protein-coupled receptor 40 (GPR40) is being recently considered to be a new potential drug target for the treatment of type 2 diabetes because of its role in the enhancement of free fatty acid-regulated glucose-stimulated insulin secretion in pancreatic β-cells. We initially identified benzyloxyphenylpropanoic acid (1b) (EC(50) = 510 nM), which was designed based on the structure of free fatty acids, as a promising lead compound with GPR40 agonist activity. Chemical modification of compound 1b led to the discovery of 3-{4-[(2',6'-dimethylbiphenyl-3-yl)methoxy]-2-fluorophenyl}propanoic acid (4p) as a potent GPR40 agonist (EC(50) = 5.7 nM). Compound 4p exhibited acceptable pharmacokinetic profiles and significant glucose-lowering effects during an oral glucose tolerance test in diabetic rats. Moreover, no hypoglycemic event was observed even after administration of a high dose of compound 4p to normal fasted rats. These pharmacological results suggest that GPR40 agonists might be novel glucose-dependent insulin secretagogues with little or no risk of hypoglycemia.

G protein-coupled receptor 40 (GPR40)/free fatty acid receptor 1 (FFA1) is a free fatty acid (FFA) receptor that mediates FFA-amplified glucose-stimulated insulin secretion in pancreatic β-cells. We previously identified (2,3-dihydro-1-benzofuran-3-yl)acetic acid derivative 2 as a candidate, but it had relatively high lipophilicity. Adding a polar functional group on 2 yielded several compounds with lower lipophilicity and little effect on caspase-3/7 activity at 30 μM (a marker of toxicity in human HepG2 hepatocytes). Three optimized compounds showed promising pharmacokinetic profiles with good in vivo effects. Of these, compound 16 had the lowest lipophilicity. Metabolic analysis of 16 showed a long-acting PK profile due to high resistance to β-oxidation. Oral administration of 16 significantly reduced plasma glucose excursion and increased insulin secretion during an OGTT in type 2 diabetic rats. Compound 16 (TAK-875) is being evaluated in human clinical trials for the treatment of type 2 diabetes.

The G protein-coupled receptor 40 (GPR40)/free fatty acid receptor 1 (FFA1) has emerged as an attractive target for a novel insulin secretagogue with glucose dependency. We previously identified phenylpropanoic acid derivative 1 (3-{4-[(2',6'-dimethylbiphenyl-3-yl)methoxy]-2-fluorophenyl}propanoic acid) as a potent and orally available GPR40/FFA1 agonist; however, 1 exhibited high clearance and low oral bioavailability, which was likely due to its susceptibility to β-oxidation at the phenylpropanoic acid moiety. To identify long-acting compounds, we attempted to block the metabolically labile sites at the phenylpropanoic acid moiety by introducing a fused-ring structure. Various fused-ring alkanoic acids with potent GPR40/FFA1 activities and good PK profiles were produced. Further optimizations of the lipophilic portion and the acidic moiety led to the discovery of dihydrobenzofuran derivative 53 ((6-{[4'-(2-ethoxyethoxy)-2',6'-dimethylbiphenyl-3-yl]methoxy}-2,3-dihydro-1-benzofuran-3-yl)acetic acid), which acted as a GPR40/FFA1 agonist with in vivo efficacy during an oral glucose tolerance test (OGTT) in rats with impaired glucose tolerance.

As part of a program to identify potent GPR40 agonists with drug-like properties suitable for clinical development, the incorporation of polar substituents was explored with the intention of decreasing the lipophilicity of our recently disclosed phenylpropanoic acid derivative 1. This incorporation would allow us to mitigate the cytotoxicity issues observed with compound 1 and enable us to move away from the multifunctional free fatty acid-like structure. Substitutions on the 2',6'-dimethylbiphenyl ring were initially undertaken, which revealed the feasibility of introducing polar functionalities at the biphenyl 4'-position. Further optimization of this position and the linker led to the discovery of several 4'-alkoxybiphenyl derivatives, which showed potent GPR40 agonist activities with the best balance in terms of improved cytotoxicity profiles and favorable pharmacokinetic properties. Among them, 3-{2-fluoro-4-[({4'-[(4-hydroxy-1,1-dioxidotetrahydro-2H-thiopyran-4-yl)methoxy]-2',6'-dimethylbiphenyl-3-yl}methyl)amino]phenyl}propanoic acid (35) exhibited a robust plasma glucose-lowering effect and insulinotropic action during an oral glucose tolerance test in rats with impaired glucose tolerance.

Starting from our previous eIF4A3-selective inhibitor , a novel series of (piperazine-1-carbonyl)pyridin-2(1)-one derivatives was designed, synthesized, and evaluated for identification of orally bioavailable probe molecules. Compounds and showed improved physicochemical and ADMET profiles, while maintaining potent and subtype-selective eIF4A3 inhibitory potency. In accord with their promising PK profiles and results from initial in vivo PD studies, compounds and showed antitumor efficacy with T/C values of 54% and 29%, respectively, without severe body weight loss. Thus, our novel series of compounds represents promising probe molecules for the in vivo pharmacological study of selective eIF4A3 inhibition.

This paper addresses a practical motion planning strategy which navigates a rigid robot in static known environment.Unlike the conventional local approaches called the artificial potential field method, major effort is first directed toward solving elliptic boundary problems expressed by the equation of heat conduction. According to temperature behaviors calculated at each grid point, the reasonable direction of heat flow is then searched through the free space and is exploited for robot navigation purposes. A computer simulation based on finite-difference techniques shows an obstacle-avoiding and local minima-free motion with the shortest path between the start and goal.

We show lasing (with the threshold of μJ order) due to morphology-dependent resonances (MDRs) from solid polystyrene spheres with volume-distributed europium (Eu) chelates. Lasing spectra depending on MDRs are reported, and a practical usefulness of the Eu chelate laser with the solid spheres is described compared with the previous one with liquid spheres.