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Tpl2 (cot/MAP3K8) is an upstream kinase of MEK in the ERK pathway. It plays an important role in Tumor Necrosis Factor-alpha (TNF-alpha) production and signaling. We have discovered that 8-halo-4-(3-chloro-4-fluoro-phenylamino)-6-[(1H-[1,2,3]triazol-4-ylmethyl)-amino]-quinoline-3-carbonitriles (4) are potent inhibitors of this enzyme. In order to improve the inhibition of TNF-alpha production in LPS-stimulated human blood, a series of analogs with a variety of substitutions around the triazole moiety were studied. We found that a cyclic amine group appended to the triazole ring could considerably enhance potency, aqueous solubility, and cell membrane permeability. Optimization of these cyclic amine groups led to the identification of 8-chloro-4-(3-chloro-4-fluorophenylamino)-6-((1-(1-ethylpiperidin-4-yl)-1H-1,2,3-triazol-4-yl)methylamino)quinoline-3-carbonitrile (34). In a LPS-stimulated rat inflammation model, compound 34 showed good efficacy in inhibiting TNF-alpha production.

The cPLA(2)alpha inhibitors we reported earlier were potent in both isolated enzyme and rat whole blood assays but have high plogD(7.4). To address these issues, reactions of electrophilic sulfonamides 9-12 were employed to incorporate various heterocyclic or heteroatom-based reagents into cPLA(2)alpha inhibitors. For example, reactions of 9 with sulfur nucleophiles such as thiophenol allowed rapid assembly of thioether analogues that were converted into the corresponding sulfoxides to afford less lipophilic derivatives. Reactions of 10 and 11 with various nitrogen nucleophiles, including aromatic heterocycles and aliphatic amines, provided an efficient way to introduce polarity into cPLA(2)alpha inhibitors. Finally, we report the first application of (2-formylphenyl)methanesulfonyl chloride, 13. Reductive amination of 2-formylphenylmethane sulfonamides allowed the introduction of various nitrogen nucleophiles. Several inhibitors obtained herein have plogD(7.4) values 3-4 units lower than previously synthesized compounds and yet maintain in vitro potency.

We have previously reported the discovery and initial SAR of the [1,7]naphthyridine-3-carbonitriles and quinoline-3-carbonitriles as Tumor Progression Loci-2 (Tpl2) kinase inhibitors. In this paper, we report new SAR efforts which have led to the identification of 4-alkylamino-[1,7]naphthyridine-3-carbonitriles. These compounds show good in vitro and in vivo activity against Tpl2 and improved pharmacokinetic properties. In addition they are highly selective for Tpl2 kinase over other kinases, for example, EGFR, MEK, MK2, and p38. Lead compound 4-cycloheptylamino-6-[(pyridin-3-ylmethyl)-amino]-[1,7]naphthyridine-3-carbonitrile (30) was efficacious in a rat model of LPS-induced TNF-alpha production.

Tumor progression loci-2 (Tpl2) (Cot/MAP3K8) is a serine/threonine kinase in the MAP3K family directly upstream of MEK. Recent studies using Tpl2 knockout mice have indicated an important role for Tpl2 in the lipopolysaccharide (LPS) induced production of tumor necrosis factor alpha (TNF-alpha) and other proinflammatory cytokines involved in diseases such as rheumatoid arthritis. Initial 4-anilino-6-aminoquinoline-3-carbonitrile leads showed poor selectivity for Tpl2 over epidermal growth factor receptor (EGFR) kinase. Using molecular modeling and crystallographic data of the EGFR kinase domain with and without an EGFR kinase-specific 4-anilinoquinazoline inhibitor (erlotinib, Tarceva), we hypothesized that we could diminish the inhibition of EGFR kinase by substitution at the C-8 position of our 4-anilino-6-aminoquinoline-3-carbonitrile leads. The 8-substituted-4-anilino-6-aminoquinoline-3-carbonitriles were prepared from the appropriate 2-substituted 4-nitroanilines. Modifications to the C-6 and C-8 positions led to the identification of compounds with increased inhibition of TNF-alpha release from LPS-stimulated rat and human blood, and these analogues were also highly selective for Tpl2 kinase over EGFR kinase. Further structure-activity based modifications led to the identification of 8-bromo-4-(3-chloro-4-fluorophenylamino)-6-[(1-methyl-1H-imidazol-4-yl)methylamino]quinoline-3-carbonitrile, which demonstrated in vitro as well as in vivo efficacy in inhibition of LPS-induced TNF-alpha production.

The following account describes our systematic effort to replace one of the carboxylate groups of our diacid thiophene PTP1B inhibitors. Active hits were validated using enzymatic assays before pursuing efforts to improve the potency. Only when the C2 carboxylic acid was replaced with another ionizable functional group was reversible and competitive inhibition retained. Use of a tetrazole ring or 1,2,5-thiadiazolidine-3-one-1,1-dioxide as a carboxylate mimetic led to the discovery of two unique starting series that showed improved permeability (PAMPA) and potency of the order of 300 nM. The SAR from these efforts underscores some of the major challenges in developing small molecule inhibitors for PTP1B.

The synthesis and structure-activity relationship of a series of indole inhibitors of cytosolic phospholipase A2alpha (cPLA2alpha, type IVA phospholipase) are described. Inhibitors of cPLA2alpha are predicted to be efficacious in treating asthma as well as the signs and symptoms of osteoarthritis, rheumatoid arthritis, and pain. The introduction of a benzyl sulfonamide substituent at C2 was found to impart improved potency of these inhibitors, and the SAR of these sulfonamide analogues is disclosed. Compound 123 (Ecopladib) is a sub-micromolar inhibitor of cPLA2alpha in the GLU micelle and rat whole blood assays. Compound 123 displayed oral efficacy in the rat carrageenan air pouch and rat carrageenan-induced paw edema models.

Leukocyte recruitment of sites of inflammation and tissue injury involves leukocyte rolling along the endothelial wall, followed by firm adherence of the leukocyte, and finally transmigration of the leukocyte across cell junctions into the underlying tissue. The initial rolling step is mediated by the interaction of leukocyte glycoproteins containing active moieties such as sialyl Lewisx (sLex) with P-selectin expressed on endothelial cells. Consequently, inhibition of this interaction by means of a small molecule P-selectin antagonist is an attractive strategy for the treatment of inflammatory diseases such as arthritis. High-throughput screening of the Wyeth chemical library identified the quinoline salicylic acid class of compounds (1) as antagonists of P-selectin, with potency in in vitro and cell-based assays far superior to that of sLex. Through iterative medicinal chemistry, we identified analogues with improved P-selectin activity, decreased inhibition of dihydrooratate dehydrogenase, and acceptable CYP profiles. Lead compound 36 was efficacious in the rat AIA model of rheumatoid arthritis.

The synthesis and structure-activity studies of a series of quinoline-3-carbonitriles as inhibitors of Tpl2 kinase are described. Potent inhibitors of Tpl2 kinase with selectivity against a panel of selected kinases in enzymatic assays and specificity in cell-based phosphorylation assays in LPS-treated human monocytes were identified. Selected inhibitors with moderate activity in human whole blood assay effectively inhibited LPS/D-Gal induced TNFalpha release when administered intraperitoneally in mice.

1,2,4-Oxadiazolidin-3,5-dione and 1,3,5-triazin-2,4,6-trione scaffolds were employed as templates to incorporate the pharmacophore requirements of cytosolic phospholipase A2alpha substrate mimetics. Inhibitors that are active in both enzyme, and cell-based assays were identified from both classes. From the SAR work carried out and modeling efforts around these templates, the triazinetrione scaffold with an additional substitution point was found to be more favorable.

A novel pyridothiophene inhibitor of PTP1B was discovered by rational screening of phosphotyrosine mimics at high micromolar concentrations. The potency of this lead compound has been improved significantly by medicinal chemistry guided by X-ray crystallography and molecular modeling. Excellent consistency has been observed between structure-activity relationships and structural information from PTP1B-inhibitor complexes.

Aggrecanases are recently discovered enzymes that cleave aggrecan, a key component of cartilage. Aggrecanase inhibitors may provide a unique means to halt the progression of cartilage destruction in osteoarthritis. The synthesis and evaluation of biphenylsulfonamidocarboxylic acid inhibitors of aggrecanase-1 are reported. Compound 24 demonstrated 89% inhibition of proteoglycan degradation at 10 μg/mL and has an oral bioavailability in rat of 35%.

The synthesis and structure-activity studies of a series of 6-substituted-4-anilino-[1,7]-naphthyridine-3-carbonitriles as inhibitors of Tpl2 kinase are described. The early exploratory work described here may lead to the discovery of compounds with significant therapeutic potential for treating rheumatoid arthritis and other inflammatory diseases.

Modification of alpha-biphenylsulfonamidocarboxylic acids led to potent and selective MMP-13 inhibitors. Compound 16 showed 100% oral bioavailability in rats and demonstrated50% inhibition of bovine cartilage degradation at 10 ng/mL.

The structure-based design and synthesis of a series of novel biphenyl sulfonamide carboxylic acids as potent MMP-13 inhibitors with selectivity over MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-14, Aggrecanase 1, and TACE are described.

The design, synthesis, and biological evaluation of arylsulfonamidooxazoles as 11beta-HSD1 inhibitors and the serendipitous discovery of beta-keto sulfones as potent 11beta-HSD1 inhibitors are described here. These two classes of compounds are not active against 11beta-HSD2 and therefore may have significant therapeutic potential for metabolic syndrome, type 2 diabetes and related metabolic dysfunctions.

The cleavage of the sn-2 ester of membrane phospholipids by phospholipase A2 has long been ascribed as the important initiation step in the production of pro-inflammatory mediators, including prostaglandins, leukotrienes and platelet-activating factor. Consequently, this enzymatic action has been implicated in the pathogenesis of a multitude of diseases, ranging from lung inflammation and arthritis to neural injuries and cardiovascular disease. The three types of phospholipase A2 that have received the most research attention are: secretory phospholipase A2 (sPLA2), cytosolic phospholipase A2 (cPLA2) and lipoprotein-associated phospholipase A2 (LpPLA2). This review will discuss the likely roles of these PLA2 in the development of the disease conditions and recent advances in the development of specific inhibitors, based on the patent literature from December 2000 to December 2003.

Synthesis of a new N -hydroxysuccinimidyl resin is described and the N -acylation with this resin provides amide products in high yields and excellent purities. This new linker is suitable for combinatorial library synthesis.

A general solid phase synthesis is described for the construction of novel amide linked oligonucleotide analogs having the glucopyranosyl configuration via solid phase N-Fmoc-type peptide chemistry. The selective binding to DNA and RNA sequences by these oligomers is characterized by measurement of melting temperatures and related thermodynamic constants.

A convenient synthesis is described for thymine, cytosine, adenine, and guanine containing, glucosamine-based N-Fmoc protected amino acids. These molecules are building blocks for the construction of novel oligonucleotide analogs via N-Fmoc type peptide chemistry.

Two efficient syntheses of the anti-AIDS drug 2',3'-dideoxycytidine from N 4 -acetylcytidine are described

Potent 3,4-disubstituted benzofuran P1' MMP-13 inhibitors have been prepared. Selectivity over MMP-2 was achieved through a substituent at the C4 position of the benzofuran P1' moiety of the molecule. By replacing a backbone benzene with a pyridine and valine with threonine, compounds (e.g., 44) with greatly reduced plasma protein binding were also obtained.

Matrix metalloprotease 12 plays a significant role in airway inflammation and remodeling. Increased expression and production of MMP-12 have been found in the lung of human COPD patients. MMP408 (14), a potent and selective MMP-12 inhibitor, was derived from a potent matrix metalloprotease 2 and 13 inhibitor via lead optimization and has good physical properties and bioavailability. The compound blocks rhMMP-12-induced lung inflammation in a mouse model and was advanced for further development for the treatment of COPD.

The synthesis and optimization of a class of trisubstituted quinazoline-2,4(1H,3H)-dione cPLA(2)alpha inhibitors are described. Utilizing pharmacophores that were found to be important in our indole series, we discovered inhibitors with reduced lipophilicity and improved aqueous solubility. These compounds are active in whole blood assays, and cell-based assay results indicate that prevention of arachidonic acid release arises from selective cPLA(2)alpha inhibition.

Different strategies for the synthesis of the 6′-α and β-fluoro derivatives of carbocyclic 2′,3′-dideoxy-3′-oxa-adenosine are described.

An efficient procedure using free radical chemistry for introducing a carbon substituent to the 3′-position of 3′-deoxythymidine is described. An application of this procedure to the synthesis of 3′-deoxy-3′-(2-propynyl)thymidine and 3′-cyanomethyl-3′-deoxythymidine, two close analogs of AZT, is presented.

Tumor necrosis factor alpha (TNFalpha) is a pro-inflammatory cytokine that controls the initiation and progression of inflammatory diseases such as rheumatoid arthritis. Tpl2 is a MAPKKK in the MAPK (i.e. ERK) pathway, and the Tpl2-MEK-ERK signaling pathway is activated by the pro-inflammatory mediators TNFalpha, interleukin (IL)-1beta, and bacterial endotoxin (lipopolysaccharide (LPS)). Moreover, Tpl2 is required for TNFalpha expression. Thus, pharmacologic inhibition of Tpl2 should be a valid approach to therapeutic intervention in the pathogenesis of rheumatoid arthritis and other inflammatory diseases in humans. We have developed a series of highly selective and potent Tpl2 inhibitors, and in the present study we have used these inhibitors to demonstrate that the catalytic activity of Tpl2 is required for the LPS-induced activation of MEK and ERK in primary human monocytes. These inhibitors selectively target Tpl2 in these cells, and they block LPS- and IL-1beta-induced TNFalpha production in both primary human monocytes and human blood. In rheumatoid arthritis fibroblast-like synoviocytes these inhibitors block ERK activation, cyclooxygenase-2 expression, and the production of IL-6, IL-8, and prostaglandin E(2), and the matrix metalloproteinases MMP-1 and MMP-3. Taken together, our results show that inhibition of Tpl2 in primary human cell types can decrease the production of TNFalpha and other pro-inflammatory mediators during inflammatory events, and they further support the notion that Tpl2 is an appropriate therapeutic target for rheumatoid arthritis and other human inflammatory diseases.

The synthesis and structure-activity relationship of a series of benzenesulfonamide indole inhibitors of cPLA(2)alpha are described. Substitution of the benzenesulfonamide led to analogues with 50-fold improvement in potency versus the unsubstituted benzenesulfonamide lead compound. Rat pharmacokinetics in a minimal formulation was used to prioritize compounds, leading to the discovery of a potent inhibitor of cPLA(2)alpha with oral efficacy in models of rat carrageenan paw edema and Ascaris suum airway challenge in naturally sensitized sheep.

Protein tyrosine phosphatase 1B (PTP1B) is a negative regulator of the insulin and leptin receptor pathways and thus an attractive therapeutic target for diabetes and obesity. Starting with a high micromolar lead compound, structure-based optimization of novel PTP1B inhibitors by extension of the molecule from the enzyme active site into the second phosphotyrosine binding site is described. Medicinal chemistry, guided by X-ray complex structure and molecular modeling, has yielded low nanomolar PTP1B inhibitors in an efficient manner. Compounds from this chemical series were found to be actively transported into hepatocytes. This active uptake into target tissues could be one of the possible avenues to overcome the poor membrane permeability of PTP1B inhibitors.

P-selectin-PSGL-1 interaction causes rolling of leukocytes on the endothelial cell surface, which subsequently leads to firm adherence and leukocyte transmigration through the vessel wall into the surrounding tissues. P-selectin is upregulated on the surface of both platelets and endothelium in a variety of atherosclerosis-associated conditions. Consequently, inhibition of this interaction by means of a small molecule P-selectin antagonist is an attractive strategy for the treatment of atherosclerosis. High-throughput screening and subsequent analoging had led to the identification of compound 1 as the lead candidate. Herein, we report the continuation of this work and the discovery of a second-generation series, the tetrahydrobenzoquinoline salicylic acids. These compounds have improved pharmacokinetic properties, and a number of them have shown oral efficacy in mouse and rat models of atherogenesis and vascular injury. The lead 31 (PSI-697), is currently in clinical development for the treatment of atherothrombotic vascular events.

Compound 1 was previously reported to be a potent inhibitor of cPLA(2)alpha in both artificial monomeric substrate and cell-based assays. However, 1 was inactive in whole blood assays previously used to characterize cyclooxygenase and lipoxygenase inhibitors. The IC(50) of 1 increased dramatically with cell number or lipid/detergent concentration. In an attempt to insert an electrophilic ketone between the indole and benzoic acid moieties, we discovered that increasing the distance between the two moieties gave a compound with activity in the GLU (7-hydroxycoumarinyl-gamma-linolenate) micelle assay, which contains lipid and detergent. Extensive structure-activity relationship work around this lead identified a potent pharmacophore for cPLA(2)alpha inhibition. The IC(50)s between the GLU micelle and rat whole blood assays correlated highly. No correlation was found for other parameters, including lipophilicity or acidity of the required acid functionality. Compounds 25, 39, and 94 emerged as potent, selective inhibitors of cPLA(2)alpha and represent well-validated starting points for further optimization.

The interaction of co-stimulatory molecules on T cells with B7 molecules on antigen presenting cells plays an important role in the activation of naive T cells. Consequently, agents that disrupt these interactions should have applications in treatment of transplant rejection as well as autoimmune diseases. To this end, specific small molecule inhibitors of human B7.1 were identified and characterized. Herein, we report the identification of potent small molecule inhibitors of the B7.1-CD28 interaction. In a high-throughput screen we identified several leads that prevented the interaction of B7.1 with CD28 with activities in the nanomolar to low micromolar range. One of these, the dihydrodipyrazolopyridinone 1, was subsequently shown to bind the V-like domain of human B7.1 at equimolar stoichiometry. With this as a starting point, we report here the synthesis and initial in vitro structure-activity relationships of a series of these compounds.

Potential E- and P-selectin inhibitors were synthesized to explore a hydrophobic area on the E-selectin surface and the PSGL-1 protein binding site on the P-selectin surface that was recently defined by crystallography. Three series of mannose-based compounds (libraries A, B, and C) were synthesized using solution phase parallel synthesis. Biological evaluation of these compounds was done using two ELISA-based assays and transferred NOE (trNOE) experiments. Some of the compounds showed better activity than sLe(x) in the P-selectin assay.

Iso-ddA ( 3 ) represents a new class of potential anti-AIDS drugs. Synthetic approaches to this compound involving nucleophilic additions to a novel carbohydrate framework are discussed.

Iso-ddA ( 3 ) represents a new class of potential anti-AIDS drugs. Synthetic approaches to this compound involving nucleophilic additions to a novel carbohydrate framework are discussed.

In this paper we report the synthesis of 2′,3′-dideoxy-9-dearaadenosine (2) and the corresponding 2′,3′-unsaturated- and 3′-deoxy- analogs, 6 and 8. These C-nucleosides are very stable towards acid and thus overcome one of the main drawbacks of 2′,3′-dideoxy-purine-nucleosides, such as the antiviral agent 2′,3′-dideoxyadenosine (ddA). However, evaluation of these compounds and some related 2′-deoxy derivatives (10-14) in the antiviral assay for the human immunodeficiency virus has revealed no significant activity.

In this paper we report an efficient synthetic route to some novel 3′-C-substituted-2,3′-dideoxy-nucleosides. The critical 3′- C-C bond was constructed by an application of free radical methodology. This type of reaction was found to be stereoselective forming exclusively the 3′-“down” isomer. The stereo-chemical assignment at C-3′ was confirmed by both nmr nOe experiments and single crystal X-ray analysis.