Novel trifluoroacetophenone derivatives as malonyl-CoA decarboxylase inhibitors.

A series of trifluoroacetophenone derivatives were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Some of the 'reverse amide' analogs were found to be potent inhibitors of MCD enzyme activity. The trifluoroacetyl group may interact with the MCD active site as the hydrate in a similar fashion to the hexafluoroisopropanol analogs reported previously.

Discovery of potent and orally available malonyl-CoA decarboxylase inhibitors as cardioprotective agents.

Discovery of 5-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)-4,5-dihydroisoxazole-3-carboxamides as a new class of malonyl-coenzyme A decarboxylase (MCD) inhibitors is described. tert-Butyl 3-(5-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)-4,5-dihydroisoxazole-3-carboxamido)butanoate (5, CBM-301940) exhibited excellent potency and in vivo PK/ADME properties. It is the most powerful stimulant of glucose oxidation reported to date in isolated working rat hearts.

Heteroaryl substituted bis-trifluoromethyl carbinols as malonyl-CoA decarboxylase inhibitors.

A series of heteroaryl-substituted bis-trifluoromethyl carbinols were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Some thiazole-based derivatives showed potent in vitro MCD inhibitory activities and significantly increased glucose oxidation rates in isolated working rat hearts.

Synthesis and structure-activity relationship of small-molecule malonyl coenzyme A decarboxylase inhibitors.

The discovery and structure-activity relationship of first-generation small-molecule malonyl-CoA decarboxylase (MCD; CoA = coenzyme A) inhibitors are reported. We demonstrated that MCD inhibitors increased malonyl-CoA concentration in the isolated working rat hearts. Malonyl-CoA is a potent, endogenous, and allosteric inhibitor of carnitine palmitoyltransferase-I (CPT-I), a key enzyme for mitochondrial fatty acid oxidation.

Aza-retinoids as novel retinoid X receptor-specific agonists.

A new structurally simple series of potent lipophilic aza-retinoids RXR agonists has been developed. SAR studies for the N-alkyl-azadienoic acids described here demonstrate that the RXR activity profile is sensitive to the N-alkyl chain length. Further, we have expanded the work to include azadienoic acids, which exhibited many accessible conformations leading to a better understanding of the SAR around the series.

Design and synthesis of heterocyclic malonyl-CoA decarboxylase inhibitors.

We have previously reported the discovery of small molecule inhibitors of malonyl-CoA decarboxylase (MCD) as novel metabolic modulators, which inhibited fatty acid oxidation and consequently increased the glucose oxidation rates in the isolated working rat hearts. MCD inhibitors were also shown to improve cardiac efficiency in rat and pig demand-induced ischemic models through the mechanism-based modulation of energy metabolism. Herein, we describe the design and synthesis of a series of novel heterocyclic MCD inhibitors with a preference for substituted imidazole and isoxazole.

Discovery and structure-activity relationship of coumarin derivatives as TNF-alpha inhibitors.

The discovery and structure-activity relationship of a novel series of coumarin-based TNF-alpha inhibitors is described. Starting from the initial lead 1a, various derivatives were prepared surrounding the coumarin core structure to optimize the in vitro inhibitory activity of TNF-alpha production by human peripheral blood mononuclear cells (hPBMC), stimulated by bacterial lipopolysaccharide (LPS). Selected compounds also demonstrated in vivo inhibition of TNF-alpha production in rats.

Malonyl coenzyme a decarboxylase inhibition protects the ischemic heart by inhibiting fatty acid oxidation and stimulating glucose oxidation.

Abnormally high rates of fatty acid oxidation and low rates of glucose oxidation are important contributors to the severity of ischemic heart disease. Malonyl coenzyme A (CoA) regulates fatty acid oxidation by inhibiting mitochondrial uptake of fatty acids. Malonyl CoA decarboxylase (MCD) is involved in the decarboxylation of malonyl CoA to acetyl CoA.

Expression, purification, and characterization of human malonyl-CoA decarboxylase.

The recombinant human malonyl-CoA decarboxylase (hMCD) was overexpressed in Escherichia coli with and without the first 39 N-terminal amino acids via a cleavable MBP-fusion construct. Proteolytic digestion using genenase I to remove the MBP-fusion tag was optimized for both the full length and truncated hMCD. The apo-hMCD enzymes were solubilized and purified to homogeneity.

Novel chromene derivatives as TNF-alpha inhibitors.

A novel series of chromene-based TNF-alpha inhibitors is described. These chromene derivatives inhibit bacterial lipopolysaccharide (LPS) stimulated production of TNF-alpha from human peripheral blood mononuclear cells (PBMC). Additionally, these compounds inhibit NF-kB mediated transcription activation.

Retinoic acid receptor ligands based on the 6-cyclopropyl-2,4-hexadienoic acid.

A series of novel cyclopropanyl methyl hexadienoic acid retinoids was designed and prepared. These compounds exhibited either selective activity as RXR agonists or pan-agonists on one or more of each of the RAR and RXR isoforms. The most potent pan-agonist 5a (RAR's EC(50)=17-59 nM; RXR's EC(50)=6-14 nM) showed good antiproliferative properties in the in vitro cancer cell lines, ME 180 and RPMI 8226.

Synthesis and Characterization of a Highly Potent and Selective Isotopically Labeled Retinoic Acid Receptor Ligand, ALRT1550.

The syntheses of two labeled homologues of (2E,4E,6E)-7-(3,5-di-tert-butylphenyl)-3-methylocta-2,4,6-trienoic acid (ALRT1550, 2), [(13)CD(3)]ALRT1550 (3) and [(3)H]ALRT1550 (4), are described in this report. ALRT1550 is an exceptionally potent antiproliferative agent which is currently in phase I/II clinical trials for acute chemotherapy. Both homologues were prepared from commercially available 3,5-di-tert-butylbenzoic acid.

Analysis of combinatorial chemistry samples by micellar electrokinetic chromatography.

A micellar electrokinetic chromatography (MEKC) method has been developed that can evaluate the purity of samples generated in combinatorial chemistry libraries. This method uses an open tube capillary (27 cm x 50 microm) along with a run buffer composed of sodium dodecyl sulfate (SDS), hydroxypropyl-beta-cyclodextrin, and sodium tetraborate coupled with UV detection. Neutral compounds and compounds that were insoluble in aqueous buffers could be analyzed under these conditions in approximately 3 min.

Novel nonsecosteroidal vitamin D mimics exert VDR-modulating activities with less calcium mobilization than 1,25-dihydroxyvitamin D3.

Background: The secosteroid 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) acts through the vitamin D receptor (VDR) to elicit many activities that make it a promising drug candidate for the treatment of a number of diseases, including cancer and psoriasis. Clinical use of 1,25(OH)2D3 has been limited by hypercalcemia elicited by pharmacologically effective doses. We hypothesized that structurally distinct, nonsecosteroidal mimics of 1,25(OH)2D3 might have different activity profiles from vitamin D analogs, and set out to discover such compounds by screening small-molecule libraries.

Matrix metalloproteinase inhibitors: a structure-activity study.

Modifications around the dipeptide-mimetic core of a hydroxamic acid based matrix metalloproteinase inhibitor were studied. These variations incorporated a variety of natural, unnatural, and synthetic amino acids in addition to modifications of the P1' and P3' substituents. The results of this study indicate the following structural requirements: (1) Two key hydrogen bonds must be present between the enzyme and potent substrates.

Sensitization of diabetic and obese mice to insulin by retinoid X receptor agonists.

Retinoic acid receptors (RAR), thyroid hormone receptors (TR), peroxisome proliferator activated receptors (PPARs) and the orphan receptor, LXR, bind preferentially to DNA as heterodimers with a common partner, retinoid X receptor (RXR), to regulate transcription. We investigated whether RXR-selective agonists replicate the activity of ligands for several of these receptors? We demonstrate here that RXR-selective ligands (referred to as rexinoids) function as RXR heterodimer-selective agonists, activating RXR: PPARgamma and RXR:LXR dimers but not RXR:RAR or RXR:TR heterodimers. Because PPARgamma is a target for antidiabetic agents, we investigated whether RXR ligands could alter insulin and glucose signalling.

A novel retinoic acid receptor-selective retinoid, ALRT1550, has potent antitumor activity against human oral squamous carcinoma xenografts in nude mice.

We have identified a novel retinoid, ALRT1550, that potently and selectively activates retinoic acid receptors (RARs). ALRT1550 binds RARs with Kd values of approximately equal to 1-4 nM, and retinoid X receptors with low affinities (Kd approximately equal to 270-556 nM). We studied the effects of ALRT1550 on cellular proliferation in squamous carcinoma cells.

Activation of specific RXR heterodimers by an antagonist of RXR homodimers.

Retinoid X receptor (RXR) plays a central role in the regulation of many intracellular receptor signalling pathways and can mediate ligand-dependent transcription, acting as a homodimer or as a heterodimer. Here we identify an antagonist towards RXR homodimers which also functions as an agonist when RXR is paired as a heterodimer to specific partners, including peroxisome proliferator-activated receptor and retinoic acid receptor. This dimer-selective ligand confers differential interactions on the transcription machinery: the antagonist promotes association with TAF110 (TATA-binding protein (TBP)-associated factor 110) and the co-repressor SMRT, but not with TBP, and these properties are distinct from pure RXR agonists.

Discovery of novel retinoic acid receptor agonists having potent antiproliferative activity in cervical cancer cells.

Retinoic acid receptor (RAR) active retinoids have proven therapeutically useful for treating certain cancers and dermatological diseases. Herein, we describe the discovery of two new RAR active trienoic acid retinoids, (2E,4E,6E)-7-(3,5-di-tert-butylphenyl)-3-methylocta-2, 4,6-trienoic acid (10a, ALRT1550) and (2E,4E,6Z)-7-(3,5-di-tert-butylphenyl)-3-methylocta-2, 4,6-trienoic acid (10b, LG100567). ALRT1550 is a RAR selective retinoid which exhibits exceptional potency in both competitive binding and cotransfection assays.

Characterization of the novel CCK analogs JMV-180, JMV-320, and JMV-332 in H345 cells.

The interaction of the novel CCK analogs JMV-180, JMV-320, and JMV-332 with CCK-B/gastrin receptors on small cell lung cancer (SCLC) cells was investigated. JMV-180, JMV-320, and JMV-332 potently inhibited specific binding of 125I-CCK-8 to CCK-B/gastrin receptors expressed on the SCLC cell line NCI-H345 (H345) with IC50 values of 4.9, 1.

Intraventricular CCK-8 reduces single meal size in the baboon by interaction with type-A CCK receptors.

Intraventricular cholecystokinin COOH-terminal octapeptide (CCK-8) decreases meal size in the meal-trained baboon. In the present study, we tested whether this action is mediated by CCK-A receptors, CCK-B receptors, or both. Intraventricular administration of the selective CCK-A receptor agonist A71623 at 1 and 10 nmol/kg suppressed 30-min meal size 69 +/- 22% and 75 +/- 7%, respectively.

Evaluation of a stable CCK agonist (A68552) in conditioned avoidance responding in mice, rats, and primates: comparison with typical and atypical antipsychotics.

In a variety of in vivo and in vitro tests, cholecystokinin (CCK) has been shown to produce effects that would suggest a functional antagonism of dopamine. On that basis, it has been hypothesized that CCK could have antipsychotic effects. We compared the CCK agonist, A68552, to the antipsychotics haloperidol (HAL), clozapine (CLOZ) and sulpiride (SULP) in various forms of conditioned avoidance using rats, mice, and cynomolgus monkeys.