Michael A. Galella

Diphenylpyridylethanamine (DPPE) derivatives as cholesteryl ester transfer protein (CETP) inhibitors.

A series of diphenylpyridylethanamine (DPPE) derivatives was identified exhibiting potent CETP inhibition. Replacing the labile ester functionality in the initial lead 7 generated a series of amides and ureas. Further optimization of the DPPE series for potency resulted in the discovery of cyclopentylurea 15d, which demonstrated a reduction in cholesterol ester transfer activity (48% of predose level) in hCETP/apoB-100 dual transgenic mice. The PK profile of 15d was suboptimal, and further optimization of the N-terminus resulted in the discovery of amide 20 with an improved PK profile and robust efficacy in transgenic hCETP/apoB-100 mice and in hamsters. Compound 20 demonstrated no significant changes in either mean arterial blood pressure or heart rate in telemeterized rats despite sustained high exposures.

Identification and optimization of a novel series of [2.2.1]-oxabicyclo imide-based androgen receptor antagonists

A novel series of [2.2.1]-oxabicyclo imide-based compounds were identified as potent antagonists of the androgen receptor. Molecular modeling and iterative drug design were applied to optimize this series. The lead compound [3aS-(3aalpha,4beta,5beta,7beta,7aalpha)]-4-(octahydro-5-hydroxy-4,7-dimethyl-1,3-dioxo-4,7-epoxy-2H-isoindol-2-yl)-2-iodobenzonitrile was shown to have potent in vivo efficacy after oral dosing in the CWR22 human prostate tumor xenograph model.

Discovery and Structure–Activity Relationship (SAR) of a Series of Ethanolamine-Based Direct-Acting Agonists of Sphingosine-1-phosphate (S1P1)

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid metabolite that regulates a multitude of physiological processes such as lymphocyte trafficking, cardiac function, vascular development, and inflammation. Because of the ability of S1P1 receptor agonists to suppress lymphocyte egress, they have great potential as therapeutic agents in a variety of autoimmune diseases. In this article, the discovery of selective, direct acting S1P1 agonists utilizing an ethanolamine scaffold containing a terminal carboxylic acid is described. Potent S1P1 agonists such as compounds 18a and 19a which have greater than 1000-fold selectivity over S1P3 are described. These compounds efficiently reduce blood lymphocyte counts in rats through 24 h after single doses of 1 and 0.3 mpk, respectively. Pharmacodynamic properties of both compounds are discussed. Compound 19a was further studied in two preclinical models of disease, exhibiting good efficacy in both the rat adjuvant arthritis model (AA) and the mouse experimental autoimmune encephalomyelitis model (EAE).

Synthesis and evaluation of carbamoylmethylene linked prodrugs of BMS-582949, a clinical p38α inhibitor.

A series of carbamoylmethylene linked prodrugs of 1 (BMS-582949), a clinical p38α inhibitor, were synthesized and evaluated. Though the phosphoryloxymethylene carbamates (3, 4, and 5) and α-aminoacyloxymethylene carbamates (22, 23, and 26) were found unstable at neutral pH values, fumaric acid derived acyloxymethylene carbamates (2, 28, and 31) were highly stable under both acidic and neutral conditions. Prodrugs 2 and 31 were also highly soluble at both acidic and neutral pH values. At a solution dose of 14.2mpk (equivalent to 10mpk of 1), 2 gave essentially the same exposure of 1 compared to dosing 10mpk of 1 itself. At a suspension dose of 142mpk (equivalent to 100mpk of 1), 2 demonstrated that it could overcome the solubility issue associated with 1 and provide a much higher exposure of 1. To our knowledge, the unique type of prodrugs like 2, 28, and 31 was not reported in the past and could represent a novel prodrug approach for secondary amides, a class of molecules frequently identified as drug candidates.

Novel tricyclic inhibitors of IKK2: discovery and SAR leading to the identification of 2-methoxy-N-((6-(1-methyl-4-(methylamino)-1,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridin-7-yl)pyridin-2-yl)methyl)acetamide (BMS-066).

The synthesis, structure-activity relationships (SAR), and biological results of pyridyl-substituted azaindole based tricyclic inhibitors of IKK2 are described. Compound 4m demonstrated potent in vitro potency, acceptable pharmacokinetic and physicochemical properties, and efficacy when dosed orally in a mouse model of inflammatory bowel disease.

[2.2.1]-Bicyclic sultams as potent androgen receptor antagonists

This letter describes the discovery, synthesis, SAR, and biological activity of [2.2.1]-bicyclic sultams as potent antagonists of the androgen receptor. Optimization of the series led to the identification of compound 25, which displayed robust pharmacodynamic effects in rats after oral dosing.

Identification of bicyclic hexafluoroisopropyl alcohol sulfonamides as retinoic acid receptor-related orphan receptor gamma (RORγ/RORc) inverse agonists. Employing structure-based drug design to improve pregnane X receptor (PXR) selectivity

We disclose the optimization of a high throughput screening hit to yield benzothiazine and tetrahydroquinoline sulfonamides as potent RORγt inverse agonists. However, a majority of these compounds showed potent activity against pregnane X receptor (PXR) and modest activity against liver X receptor α (LXRα). Structure-based drug design (SBDD) led to the identification of benzothiazine and tetrahydroquinoline sulfonamide analogs which completely dialed out LXRα activity and were less potent at PXR. Pharmacodynamic (PD) data for compound 35 in an IL-23 induced IL-17 mouse model is discussed along with the implications of a high Ymax in the PXR assay for long term preclinical pharmacokinetic (PK) studies.

Protected Chloroethyl and Chloropropyl Amines as Conformationally Unrestricted Annulating Reagents

The purpose of this letter is to document the use of protected chloroethyl and chloropropyl amines as conformationally unrestricted ambiphilic reagents that undergo annulation reactions with Michael acceptors. This reaction is wide in scope and utilizes reagents that are commercially available, inexpensive, and stable. Furthermore, this reaction is easy to execute and proceeds rapidly.

Discovery and synthesis of cyclohexenyl derivatives as modulators of CC chemokine receptor 2 activity.

A novel cyclohexenyl series of CCR2 antagonists has been discovered. This series of small, rigid compounds exhibits submicromolar binding affinity for CCR2. Modification of the substituents on the cyclohexene ring led to the identification of potent CCR2 antagonists. Progress from initial lead 5 (IC50=700nM) to (-)-38 (IC50=9.0nM) is discussed.

Discovery and synthesis of tetrahydropyrimidinedione-4-carboxamides as endothelial lipase inhibitors

Endothelial lipase (EL) inhibitors have been shown to elevate HDL-C levels in pre-clinical murine models and have potential benefit in prevention and treatment of cardiovascular diseases. Modification of the 1-ethyl-3-hydroxy-1,5-dihydro-2H-pyrrol-2-one (DHP) lead, 1, led to the discovery of a series of potent tetrahydropyrimidinedione (THP) EL inhibitors. Synthesis and SAR studies including modification of the amide group, together with changes on the pyrimidinone core led to a series of arylcycloalkyl, indanyl, and tetralinyl substituted 5-amino or 5-hydroxypyrimidinedione-4-carboxamides. Several compounds were advanced to PK evaluation. Among them, compound 4a was one of the most potent with measurable ELHDL hSerum potency and compound 3g demonstrated the best overall pharmacokinetic parameters.