Identification of an aminothiazole series of RORβ modulators

Crystallography has identified stearic acid, ALRT 1550 and ATRA as ligands that bind RORβ, however, none of these molecules represent good starting points to develop optimized small molecule modulators. Recently, Compound 1 was identified as a potent dual RORβ and RORγ inverse agonist with no activity towards RORα (Fig. 1). To our knowledge, this is one of only two small molecule RORβ inverse agonists identified in the primary literature from a tractable chemical series and represents an ideal starting point from which to design RORβ-selective modulators. Herein we describe our SAR optimization efforts that led to a series of potent neutral antagonists of RORβ.     

Design and synthesis of an aminopiperidine series of γ-secretase modulators

The design, synthesis, and SAR of cyclic diamines as novel γ secretase modulators (GSMs) are presented in this Letter. Starting from information in the literature and in-house cyclic diamines library, we have found a 3(S)-aminopiperidine as a potent structure for lowering Aβ42 production both in vitro and in vivo.     

Semisynthesis and antiproliferative evaluation of a series of 3′-aminoflavones

A series of 3′-aminoflavones 5,6,7,8-tetra- or 5,7-dioxygenated on the A-ring was synthesized from tangeretin or naringin, two natural Citrus flavonoids. These flavones were evaluated for antiproliferative activity, activation of apoptosis, and inhibition of tubulin assembly. The most antiproliferative flavones exhibit a common 5-hydroxy-6,7,8-trimethoxy substitution pattern on the A-ring.     

Synthesis of new series of α-cyclodextrin esters as dopamine carrier molecule

A new series of amphiphilic α-cyclodextrins were synthesized by grafting N-acylated amino acids [valine, leucine, phenylalanine, methionine, and tryptophan (3a-e)] to the primary hydroxyl groups via ester bond formation. The synthetic pathway involves selective hexa-bromination of the primary hydroxyls followed by per-substitution with the carboxylate moiety of the N-acetyl residues in the presence of DBU (1,8-diazabicyclo[5,4,0]undec-7-ene). The ability of the synthetic compounds for the extraction of dopamine was studied. The results showed a considerable ability of some of the amphiphilic compounds for the extraction of dopamine into octanol phase from water. To complete the study, the binding affinity of dopamine toward the synthetic host molecules was calculated by using of the molecular docking technique.     

Discovery of a novel series of quinolone α7 nicotinic acetylcholine receptor agonists

High throughput screening led to the identification of a novel series of quinolone α7 nicotinic acetylcholine receptor (nAChR) agonists. Optimization of an HTS hit (1) led to 4-phenyl-1-(quinuclidin-3-ylmethyl)quinolin-2(1H)-one, which was found to be potent and selective. Poor brain penetrance in this series was attributed to transporter-mediated efflux, which was in turn due to high pK_a. A novel 4-fluoroquinuclidine significantly lowered the pK_a of the quinuclidine moiety, reducing efflux as measured by a Caco-2 assay.     

Optimisation of pharmacokinetic properties in a neutral series of 11β-HSD1 inhibitors

11β-HSD1 is increasingly seen as an attractive target for the treatment of type II diabetes and other elements of the metabolic syndrome. In this program of work we describe how a series of neutral 2-thioalkyl-pyridine 11β-HSD1 inhibitors were optimized in terms of their pharmacokinetic properties to give compounds with excellent bioavailability in both rat and dog through a core change to pyrimidine. A potential reactive metabolite issue with 4-thioalkyl-pyrimidines was circumvented by a switch from sulfur to carbon substitution.     

Decomposition of stationary time series — Finding the highly correlated components of stochastic processes

A stationary time series can be expressed by a sum of time series (components) occuring in a descending order of the magnitude of their autocorrelations. A few such components suffice for approximating the time series with a good accuracy. Since the first component is a highly correlated one, it is easier to work with in applications. To perform the decomposition a particular optimization operator (optimator) with quadratic criterion called -optimator is introduced. The -optimator involves a shape parameter, so the decomposition is unique for any given value of that parameter. It is shown that in any decomposition the first component has a larger autocorrelation than the given i.e. original time series. Therefore weakly correlated processes can also involve highly correlated components. Existence and uniqueness of the components is proved and some examples are worked out to illustrate the decomposition procedure.     

Pyrimidone-based series of glucokinase activators with alternative donor–acceptor motif

Glucokinase activators are a class of experimental agents under investigation as a therapy for Type 2 diabetes mellitus. An X-ray crystal structure of a modestly potent agent revealed the potential to substitute the common heterocyclic amide donor–acceptor motif for a pyridone moiety. We have successfully demonstrated that both pyridone and pyrimidone heterocycles can be used as a potent donor–acceptor substituent. Several sub-micromolar analogs that possess the desired partial activator profile were synthesized and characterized. Unfortunately, the most potent activators suffered from sub-optimal pharmacokinetic properties. Nonetheless, these donor–acceptor motifs may find utility in other glucokinase activator series or beyond.     

Synthesis and anti-parasitic activity of a novel quinolinone–chalcone series

A series of novel quinolinone–chalcone hybrids and analogues were designed, synthesized and their biological activity against the mammalian stages of Trypanosoma brucei and Leishmania infantum evaluated. Promising molecular scaffolds with significant microbicidal activity and low cytotoxicity were identified. Quinolinone–chalcone 10 exhibited anti-parasitic properties against both organisms, being the most potent anti-L. infantum agent of the entire series (IC₅₀ value of 1.3 ± 0.1 μM). Compounds 4 and 11 showed potency toward the intracellular, amastigote stage of L. infantum (IC₅₀ values of 2.1 ± 0.6 and 3.1 ± 1.05 μM, respectively). Promising trypanocidal compounds include 5 and 10 (IC₅₀ values of 2.6 ± 0.1 and 3.3 ± 0.1 μM, respectively) as well as 6 and 9 (both having IC₅₀ values of <5 μM). Chemical modifications on the quinolinone–chalcone scaffold were performed on selected compounds in order to investigate the influence of these structural features on antiparasitic activity.     

Effect of fatty acids of ω6 series on the biosynthesis of arachidonic acid in HTC cells

Summary The influence of the preincubation of HTC cells with fatty acids of 6 series and columbinic acid (St, 9c, 12c 18:3) on the biosynthesis of arachidonic acid was studied. The cells were incubated on a chemically defined medium with or without the addition of unlabeled linoleic, -linolenic, eicosatrienoic, arachidonic, docosatetraenoic, docosapentaenoic and columbinic acids. After 24 hr of preincubation in the presence of the aforementioned fatty acids, [1-¹⁴C]eicosa-8,11,14-trienoic acid was added to the culture medium as the only lipidic source. Twenty-four hours later the synthesis of arachidonic acid and the fatty acid composition of the cells were determined. At 20 MM concentration the 6 fatty acids studied except docosapentaenoic acid produced an increase on the biosynthesis of arachidonic acid compared to the cells incubated in the absence of unlabeled fatty acids in the medium. The fatty acids added to the culture medium were incorporated into the cells and modified their fatty acid composition. Columbinic acid, with a similar structure to linoleic acid, also produced a significant increase on the conversion of eicosatrienoic acid to arachidonic acid. These results would suggest that the effect of both, linoleic and columbinic acids, may be adscribed to their configuration and not necessarily to their transformation in higher homologs, since columbinic acid is unable to be desaturated.All authors are members of the Carrera del Investigador Cientifico of the Consejo Nacional de Investigaciones Cientifícas y Técnicas, Argentina.     

Design and synthesis of a novel series of cyanoindole derivatives as potent γ-secretase modulators

The discovery, design and synthesis of a new series of GSMs is described. The classical imidazole heterocycle has been replaced by a cyano group attached to an indole nucleus. The exploration of this series has led to compound 26-S which combined high in vitro and in vivo potency with an acceptable drug-like profile.     

Neglect of medical evidence of torture in Guantánamo Bay: a case series

Background

In the wake of the September 11, 2001 attacks on the US, the government authorized the use of “enhanced interrogation” techniques that were previously recognized as torture. While the complicity of US health professionals in the design and implementation of US torture practices has been documented, little is known about the role of health providers, assigned to the US Department of Defense (DoD) at the US Naval Station Guantánamo Bay, Cuba (GTMO), who should have been in a position to observe and document physical and psychological evidence of torture and ill treatment.

Methods and Findings

We reviewed GTMO medical records and relevant case files (client affidavits, attorney–client notes and summaries, and legal affidavits of medical experts) of nine individuals for evidence of torture and ill treatment and documentation by medical personnel. In each of the nine cases, GTMO detainees alleged abusive interrogation methods that are consistent with torture as defined by the UN Convention Against Torture as well as the more restrictive US definition of torture that was operational at the time. The medical affidavits in each of the nine cases indicate that the specific allegations of torture and ill treatment are highly consistent with physical and psychological evidence documented in the medical records and evaluations by non-governmental medical experts. However, the medical personnel who treated the detainees at GTMO failed to inquire and/or document causes of the physical injuries and psychological symptoms they observed. Psychological symptoms were commonly attributed to “personality disorders” and “routine stressors of confinement.” Temporary psychotic symptoms and hallucinations did not prompt consideration of abusive treatment. Psychological assessments conducted by non-governmental medical experts revealed diagnostic criteria for current major depression and/or PTSD in all nine cases.

Conclusion

The findings in these nine cases from GTMO indicate that medical doctors and mental health personnel assigned to the DoD neglected and/or concealed medical evidence of intentional harm. Please see later in the article for the Editors'' Summary     

Synthesis and PKCθ inhibitory activity of a series of 4-indolylamino-5-phenyl-3-pyridinecarbonitriles

A series of 4-indolylamino-5-phenyl-3-pyridinecarbonitrile inhibitors of PKCθ were synthesized as potential anti-inflammatory agents. The effects of specific substitution on the 5-phenyl moiety and variations of the positional isomers of the 4-indolylamino substituent were explored. This study led to the discovery of compound 12d, which had an IC₅₀ value of 18 nM for the inhibition of PKCθ.     

Synthesis and structure–activity relationship of a novel series of heterocyclic sulfonamide γ-secretase inhibitors

γ-Secretase inhibitors have been shown to reduce the production of β-amyloid, a component of the plaques that are found in brains of patients with Alzheimer’s disease. A novel series of heterocyclic sulfonamide γ-secretase inhibitors that reduce β-amyloid levels in cells is reported. Several examples of compounds within this series demonstrate a higher propensity to inhibit the processing of amyloid precursor protein compared to Notch, an alternative γ-secretase substrate.     

Discovery and structure–activity relationship of a novel spirocarbamate series of NPY Y5 antagonists

A novel series of trans-8-aminomethyl-1-oxa-3-azaspiro[4.5]decan-2-one derivatives was identified with potent NPY Y5 antagonist activity. Optimization of the original lead furnished compounds 23p and 23u, which combine sub-nanomolar Y5 activity with metabolic stability, oral bioavailability, brain penetration and strong preclinical profile for development. Both compounds significantly inhibited the food intake induced by a Y5 selective agonist with minimal effective doses of 3 mg/kg po.     

3,5-Disubstituted-indole-7-carboxamides: the discovery of a novel series of potent, selective inhibitors of IKK-β

The discovery and hit-to-lead exploration of a novel series of selective IKK-β kinase inhibitors is described. The initial lead fragment 3 was identified by pharmacophore-directed virtual screening. Homology model-driven SAR exploration of the template led to potent inhibitors, such as 12, which demonstrate efficacy in cellular assays and possess encouraging developability profiles.     

Discovery and optimization of a series of 2-aminothiazole-oxazoles as potent phosphoinositide 3-kinase γ inhibitors

A novel series of 2-aminothiazole-oxazoles was designed and synthesized as part of efforts to develop potent phosphoinositide 3-kinase γ (PI3Kγ) inhibitors. The modification of a high-throughput screening hit, compound 1, resulted in the identification of compounds 10 and 15, which displayed potent inhibitory activities in enzyme-based and cell-based assays.     

Diamide amino-imidazoles: a novel series of γ-secretase inhibitors for the treatment of Alzheimer's disease

The synthesis and structure-activity relationship (SAR) of a novel series of di-substituted imidazoles, derived from modification of DAPT, are described. Subsequent optimization led to identification of a highly potent series of inhibitors that contain a β-amine in the imidazole side-chain resulting in a robust in vivo reduction of plasma and brain Aβ in guinea pigs. The therapeutic index between Aβ reductions and changes in B-cell populations were studied for compound 10h.