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Targeting nuclear receptor RORγ is recognized to be beneficial in multiple autoimmune disorders. We disclosed new indole analogues as potent RORγ inverse agonists. RO-2 as one of the potent and orally bioavailable compounds was evaluated in various models of autoimmune disorder. It showed potent suppression of downstream markers of RORγt activity in murine and human primary cells, ex vivo PD assay and in multiple animal models of autoimmune diseases. The results indicate the potential of these indole analogues as orally bioavailable small molecule inverse agonists of RORγt, efficacious in various Th17 driven models of autoimmune disorders.

Conceptual design and modification of urea moiety in chemotype PF-3845/04457845, the bench marking irreversible inhibitor of fatty acid amide hydrolase (FAAH), led to discovery of a novel nicotinamide-based lead 12a having reversible mechanism of action. Focused SAR around the pyridine heterocycle (Ar) in 12a (Tables 1 and 2) resulted into four shortlisted compounds, (−)-12a, (−)-12i, (−)-12l–m. The required (−)-enantiomers were obtained via diastereomeric resolution of a novel chiral dissymmetric intermediate 15. Based on comparative profile of FAAH potency, metabolic stability in liver microsome, liability of inhibiting major hCYP450 isoforms, rat PK, and brain penetration ability, two SAR optimized compounds, (−)-12l and (−)-12m, were selected for efficacy study in rat model of chemotherapy-induced peripheral neuropathy (CIPN). Both the compounds exhibited dose related antihyperalgesic effects, when treated with 3–30 mg/kg po for 7 days. The effects at 30 mg/kg are comparable to that of PF-04457845 (10 mg/kg) and Tramadol (40 mg/kg).

GPR91, a 7TM G-Protein-Coupled Receptor, has been recently deorphanized with succinic acid as its endogenous ligand. Current literature indicates that GPR91 plays role in various pathophysiology including renal hypertension, autoimmune disease and retinal angiogenesis. Starting from a small molecule high-throughput screening hit 1 (hGPR91 IC(50): 0.8 μM)-originally synthesized in Merck for Bradykinin B(1) Receptor (BK(1)R) program, systematic structure-activity relationship study led us to discover potent and selective hGPR91 antagonists e.g. 2c, 4c, and 5 g (IC(50): 7-35 nM; >1000 fold selective against hGPR99, a closest related GPCR; >100 fold selective in Drug Matrix screening). This initial work also led to identification of two structurally distinct and orally bio-available lead compounds: 5g (%F: 26) and 7e (IC(50): 180 nM; >100 fold selective against hGPR99; %F: 87). A rat pharmacodynamic assay was developed to characterize the antagonists in vivo using succinate induced increase in blood pressure. Using two representative antagonists, 2c and 4c, the GPR91 target engagement was subsequently demonstrated using the designed pharmacodynamic assay.

A series of colored hydrocarbon and fluorocarbon tagged 1-fluoro-4-alkylamino-anthraquinones and 1,4-bis-alkylamino-anthraquinone probe molecules were synthesized from a (fluorinated) alkyl amine and 1,4-difluoroanthraquinone to aid in the development of fluorous separation applications. The anthraquinones displayed stacking of the anthraquinone tricycle and interdigitation of the (fluorinated) alkyl chains in the solid state. Furthermore, intramolecular N–H⋯O hydrogen bonds forced the hydrocarbon and fluorocarbon tags into a conformation pointing away from the anthraquinone tricycle, with the angle of the tricycle plane normal and the main (fluorinated) alkyl vector ranging from 1° to 39°. Separation of the probe molecules on fluorous silica gel showed that the degree of fluorination of the probe molecules plays only a minor role with most eluents (e.g., hexane/ethyl acetate and methyl nonafluorobutyl ethers/ethyl acetate). However, toluene as eluent caused a pronounced separation by degree of fluorination for fluorocarbon, but not hydrocarbon tagged probe molecules on both silica gel and fluorous silica gel. These studies suggest that hydrocarbon and fluorocarbon tagged anthraquinones are useful probe molecules for the development of laboratory scale fluorous separation applications.

Several iodobenzenes form tetraarylstannanes, in addition to other products, under reaction conditions typically employed for the Ullmann reaction, i.e., activated copper bronze (a copper−tin alloy) and 7 days at 230 °C. The isolated yields of the tetraarylstannanes were low to good (8−58%). Significantly higher yields (54−64%) of tetraphenylstannane were obtained by the direct reaction of iodobenzene with an excess of tin powder (iodobenzene:tin = 1:1 w/w) under the same conditions. Crystal structure analysis reveals that tetrakis(4-carbomethoxyphenyl)stannane crystallizes in a tetragonal space group and has 4 symmetry, which is the case for many symmetrical tetraarylstannanes. However, tetrakis(2,4-dichlorophenyl)stannane, tetrakis(3,4-dichlorophenyl)stannane, and tetrakis(2,4-dimethylphenyl)stannane do not crystallize in a tetragonal space group and do not have real 4 symmetry.

Palladium-catalyzed CC and CN bond forming reactions of aryl halides continue to be a major focus in catalysis research for the fine chemical industry. Still there exists a significant need for the development of more active and productive palladium catalysts. Although an increasing number of new catalysts is reported, it is often difficult to compare them. Here, we present a more detailed comparison of the catalytic performance of different monocarbenepalladium(0) complexes and various so-called in situ palladium phosphine and carbene catalysts in Suzuki, Kumada, and Buchwald–Hartwig amination reactions. Depending on the type of coupling reaction good to excellent yields of the desired products are obtained in the presence of both carbene- and phosphine-based catalysts. In general, phosphine-based catalysts appear to be more efficient for amination and Suzuki reactions of aryl chlorides. On the other hand, the carbene-based palladium catalysts work well in Kumada couplings of various aryl chlorides.

Application of acidic clays as heterogeneous catalysts for the Michael type addition reaction of aliphatic amines to α,β-ethylenic compounds is presented. Aromatic amines do not participate in this transformation.

The mol­ecule of the title compound, [Sn(C6H2Cl3)4], occupies a general position in the crystal structure, but shows an approximate \overline{4} mol­ecular symmetry.

The application of a new type of polymer anchored chiral amino-oxazolinyl ligand as catalyst for the enantioselective addition of diethylzinc to aldehydes is reported. The catalyst is effective at a low ligand concentration and can be reused with minimal loss of activity.

The ketones are enantioselectively reduced to the corresponding alcohols employing Fe(OAc)2 and a chiral diphosphine as catalyst, and either diethoxy(methyl)silane or PMHS as reducing agent.

The iron-catalyzed reduction of aromatic nitro compounds to the corresponding anilines applying organosilanes is reported. In the presence of FeX(2)-R(3)P catalysts a series of nitroarenes is selectively reduced tolerating a wide range of functional groups.

The application of solid acidic catalysts for the selective removal of N-Boc protection is presented in this report. Montmorillonite K10 was found to be an effective catalyst in removing aromatic N-Boc groups while leaving aliphatic N-Boc amines untouched.

Carboxylic acids are regenerated from their corresponding substituted allyl esters by Montmorillonite K-10 using microwave irradiation under solvent free conditions to afford enhanced yields and reduced reaction times compared to thermal conditions.

A simple and environmentally safe procedure for the preparation of 2-(o-aminophenyl)oxazolines from isatoic anhydride is presented. A series of chiral derivatives of the title compound is prepared in moderate yield via natural kaolinitic clay catalyzed reactions with optically pure 2-aminoalcohols. Reaction of polymer-supported isatoic anhydride under these conditions with chiral 2-aminoalcohols proceeds to furnish polymer-anchored analogues.

Application of acidic clays as heterogeneous catalysts for the Michael type addition reaction of aliphatic amines to α,β-ethylenic compounds is presented. Aromatic amines do not participate in this transformation.

The application of a new type of polymer anchored chiral amino-oxazolinyl ligand as catalyst for the enantioselective addition of diethylzinc to aldehydes is reported. The catalyst is effective at a low ligand concentration and can be reused with minimal loss of activity.

The reduction of ketones with polymethylhydrosiloxane (PMHS) gives the corresponding alcohols in good to excellent yield applying iron-based catalyst systems. In the case of prochiral ketones, the use of Fe(OAc)(2)/(S,S)-Me-DuPhos leads to high enantioselectivity up to 99% ee. The reaction proceeds in the presence of several functional groups such as esters, halides as well as conjugated double bonds, with high chemoselectivity. The advantage of this protocol is that the reaction requires no activating agents or additives.

The iron-catalyzed reduction of aromatic nitro compounds to the corresponding anilines applying organosilanes is reported. In the presence of FeX(2)-R(3)P catalysts a series of nitroarenes is selectively reduced tolerating a wide range of functional groups.

The application of solid acidic catalysts for the selective removal of N-Boc protection is presented in this report. Montmorillonite K10 was found to be an effective catalyst in removing aromatic N-Boc groups while leaving aliphatic N-Boc amines untouched.

A general and highly chemoselective hydrosilylation of aldehydes using iron catalysts is reported. Fe(OAc)2 in the presence of tricyclohexylphosphine as ligand and polymethylhydrosiloxane (PMHS) as an economical hydride source forms an efficient catalyst system for the hydrosilylation of a variety of aldehydes. Aryl, heteroaryl, alkyl and alpha,beta-unsaturated aldehydes are successfully reduced to the corresponding primary alcohols. Broad substrate scope and high tolerance against several functional groups make the process synthetically useful.

Studies of xenobiotic disposition in rodents often employ experimental designs using differing routes of administration. In an effort to investigate the effects of route of administration on enantioselective disposition of xenobiotics, a chiral polychlorinated biphenyl (PCB), racemic PCB 136, was administered as a single dose (50 mg/kg body weight) to male or female C57BL/6 mice either orally or via intraperitoneal injection. Mice were sacrificed after either 3 or 6 days, and blood and organs were collected for PCB analysis. Intraperitoneal injection of PCB 136 produced statistically higher PCB levels in blood and organs than did the oral administration. Tissue levels were higher after 3 days than those after 6 days. Enantioselective analysis showed that (+)-PCB 136 was enriched in most organs, with the most pronounced enrichment found in the liver and the brain of animals dosed orally or by intraperitoneal injection, respectively. Significantly higher retained enantiomeric fractions of PCB 136 were found in the oral treatment groups compared with those found in intraperitoneal treatment groups, possibly as a result of the lower PCB levels in oral treatment groups. Therefore, the choice of administration route may well have implications for the enantioselective disposition of PCB 136 and other chiral substances. Chirality, 2006. © 2006 Wiley-Liss, Inc.

The crystal structure of PCB 77 (3,3',4,4'-tetrachlorobiphenyl, C(12)H(6)Cl(4)), a dioxin-like PCB congener, is described. The dihedral angle of PCB 77 is 43.94(6) degrees, which is slightly larger than calculated or experimental dihedral angles of biphenyl derivatives in solution but smaller than experimental dihedral angles in the gas phase.

The application of clay as a catalyst for acetonide protection of N(Boc)-amino alcohols and 1,2-diols to obtain good to excellent yields of the acetonide derivatives is described. Acetonide deprotection to obtain the parent amino alcohol was carried out using a similar catalyst in the presence of methanol as solvent. The reaction takes place at room temperature within 2 h to give the parent amino alcohol in quantitative yield keeping the N(Boc) group intact.

The University of Iowa, Department ofOccupational and Environment al Health, 100Oakdale Campus, 221 IREH, Iowa City, IA52242-5000 , USACorrespondenc e e-mail:hans-joachim-le hmler@uiowa .eduKey indicato rsSingle-cryst al X-ra y studyT = 9 0 KMean ! (CÐC) = 0.004 AuR facto r = 0.023wR facto r = 0.061Data-to-param eter ratio = 13.6For details of h o w thes e key indicators wereautomatica lly derived from the article, seehttp://journa ls.iucr.org/e.Rece ived 20 February 2007Accepte d 21 February 2007# 2007 Internat ional Union of Crysta llographyAll rights reserved

Carboxylic acids are regenerated from their corresponding substituted allyl esters by Montmorillonite K-10 using microwave irradiation under solvent free conditions to afford enhanced yields and reduced reaction times compared to thermal conditions.

A simple method is described for the preparation of 1,3-dihydrofuro[4,3-b]quinolin-3-ol starting from aniline and methyl acetoacetate using selenium dioxide.

A practical synthesis of a novel class of phosphine ligands, phosphino substituted N-aryl pyrroles (PAP ligands), has been developed. These ligands are applied in the palladium-catalyzed coupling of a variety of aryl and heteroaryl chlorides with phenylboronic acid showing exceedingly high turnover numbers at mild reaction temperatures and even at room temperature.