Enantioselective Synthesis of 8-Hydroxyquinoline Derivative, Q134 as a Hypoxic Adaptation Inducing Agent

Hypoxia is a common feature of neurodegenerative diseases, including Alzheimer’s disease that may be responsible for disease pathogenesis and progression. Therefore, the hypoxia-inducible factor (HIF)1 system, responsible for hypoxic adaptation, is a potential therapeutic target to combat these diseases by activators of cytoprotective protein induction. We have selected a candidate molecule from our cytoprotective hydroxyquinoline library and developed a novel enantioselective synthesis for the production of its enantiomers. The use of quinidine or quinine as a catalyst enabled the preparation of enantiomer-pure products. We have utilized in vitro assays to evaluate cytoprotective activity, a fluorescence-activated cell sorting (FACS) based assay measuring mitochondrial membrane potential changes, and gene and protein expression analysis. Our data showed that the enantiomers of Q134 showed potent and similar activity in all tested assays. We have concluded that the enantiomers exert their cytoprotective activity via the HIF1 system through HIF1A protein stabilization

Synthesis and Cytoprotective Characterization of 8- Hydroxyquinoline Betti Products

The 8-hydroxyquinoline pharmacophore scaffold has been shown to possess a range of activities as metal chelation, enzyme inhibition, cytotoxicity, and cytoprotection. Based on our previous findings we set out to optimize the scaffold for cytoprotective activity for its potential application in central nervous system related diseases. A 48-membered Betti-library was constructed by the utilization of formic acid mediated industrial-compatible coupling with sets of aromatic primary amines such as anilines, oxazoles, pyridines, and pyrimidines, with (hetero)aromatic aldehydes and 8-hydroxiquinoline derivatives. After column chromatography and re-crystallization, the corresponding analogues were obtained in yields of 13–90%. The synthesized analogs were optimized with the utilization of a cytoprotection assay with chemically induced oxidative stress, and the most active compounds were further tested in orthogonal assays, a real time cell viability method, a fluorescence-activated cell sorting (FACS)-based assay measuring mitochondrial membrane potential changes, and gene expression analysis. The best candidates showed potent, nanomolar activity in all test systems and support the need for future studies in animal models of central nervous system (CNS) disorders

Enantioszelektív heterogén katalitikus reakciók = Enantioselective heterogeneous catalytic reactions

Prokirális C=C vegyületek és prokirális ketonok heterogén katalitikus enantioszelektív hidrogénezésének vizsgálatával királis vegyületek előállítása volt a cél. A kutatás során eddig nem vizsgált különböző szerkezetű ","-telítetlen karbonsavak, telítetlen dikarbonsavak, fluoro telítetlen karbonsavak, dihidropiranil- és tetrahidropiridil karbonsavak, N-acilamino dehidrokarbonsavak valamint fluoroketonok és szteroidketonok hidrogénezését tanulmányoztuk folyadékfázisban, sztatikus reaktorokban. Egyes vegyülettípusok királis hidrogénezését kiterjesztettük a gazdaságosabban hasznosítható folyamatos működésű reaktorrendszerre is. Az előállított királis vegyületek - az eljárások fejlesztése esetén - hasznosítható vegyületek lehetnek a szintetikus szerves vegyiparban, s ezen belül a gyógyszeriparban. A hidrogénezési reakciók mechanizmusának és ezen belül a királis indukció eredetének minél mélyebb megismeréséhez kísérleti bizonyítékokat szolgáltattunk NMR-spektroszkópia, elméleti számítások és újabb cinkona-alapú királis módosítók vizsgálatával. Új kísérleti adatokkal igazoltuk az Orito reakció korábban feltételezett, de eddig nem igazolt un. nukleofil mechanizmusát. Az e téren folytatott kutatások új jelenségek felismeréséhez is vezettek. | The enantioselective heterogeneous catalytic hydrogenation of prochiral C=C bonds and prochiral ketones were studied for the preparation of enantiopure compounds. Liquid phase hydrogenation of various compounds not studied before, such as ","-unsaturated carboxylic acids, unsaturated dicarboxylic acids, unsaturated fluorocarboxylic acids, dihydropyranil- and dihydropyridyl carboxylic acids, N-acylaminodehydrocarboxylic acids, as well as fluoroketones and steroid ketones were examined in a static reactor. For the enantioselective hydrogenation of certain type of compounds the more economical flow reactor system was also used. After the development of the procedure the prepared chiral compounds would be useful ones in the organic chemical industry, especially for the pharmaceutical industry. The study of the new cinchona based chiral modifiers, as well as the NMR spectroscopy and the theoretical calculations provided a deeper insight into the mechanism of the enantioselective hydrogenation, especially into the origin of the chiral induction. On the basis of new experimental data we verified the so called nucleophilic mechanism of the Orito reaction, which was postulated but not confirmed earlier. During this research work new phenomena were also recognized

Polyunsaturated fatty acids synergize with lipid droplet binding thalidomide analogs to induce oxidative stress in cancer cells

<p>Abstract</p> <p>Background</p> <p>Cytoplasmic lipid-droplets are common inclusions of eukaryotic cells. Lipid-droplet binding thalidomide analogs (2,6-dialkylphenyl-4/5-amino-substituted-5,6,7-trifluorophthalimides) with potent anticancer activities were synthesized.</p> <p>Results</p> <p>Cytotoxicity was detected in different cell lines including melanoma, leukemia, hepatocellular carcinoma, glioblastoma at micromolar concentrations. The synthesized analogs are non-toxic to adult animals up to 1 g/kg but are teratogenic to zebrafish embryos at micromolar concentrations with defects in the developing muscle. Treatment of tumor cells resulted in calcium release from the endoplasmic reticulum (ER), induction of reactive oxygen species (ROS), ER stress and cell death. Antioxidants could partially, while an intracellular calcium chelator almost completely diminish ROS production. Exogenous docosahexaenoic acid or eicosapentaenoic acid induced calcium release and ROS generation, and synergized with the analogs <it>in vitro</it>, while oleic acid had no such an effect. Gene expression analysis confirmed the induction of ER stress-mediated apoptosis pathway components, such as GADD153, ATF3, Luman/CREB3 and the ER-associated degradation-related HERPUD1 genes. Tumor suppressors, P53, LATS2 and ING3 were also up-regulated in various cell lines after drug treatment. Amino-phthalimides down-regulated the expression of CCL2, which is implicated in tumor metastasis and angiogenesis.</p> <p>Conclusions</p> <p>Because of the anticancer, anti-angiogenic action and the wide range of applicability of the immunomodulatory drugs, including thalidomide analogs, lipid droplet-binding members of this family could represent a new class of agents by affecting ER-membrane integrity and perturbations of ER homeostasis.</p

Q50, an Iron-Chelating and Zinc-Complexing Agent, Improves Cardiac Function in Rat Models of Ischemia/Reperfusion-Induced Myocardial Injury

Background: Reperfusion of ischemic myocardium may contribute to substantial cardiac tissue damage, but the addition of iron chelators, zinc or zinc complexes has been shown to prevent heart from reperfusion injury. We investigated the possible beneficial effects of an iron-chelating and zinc-complexing agent, Q50, in rat models of ischemia/reperfusion (I/R)-induced myocardial infarction and on global reversible myocardial I/R injury after heart transplantation. Methods and Results: Rats underwent 45-min myocardial ischemia by left anterior descending coronary artery ligation followed by 24h reperfusion. Vehicle or Q50 (10mg/kg, IV) were given 5min before reperfusion. In a heart transplantation model, donor rats received vehicle or Q50 (30mg/kg, IV) 1h before the onset of ischemia. In myocardial infarcted rats, increased left ventricular end-systolic and end-diastolic volumes were significantly decreased by Q50 post treatment as compared with the sham group. Moreover, in I/R rat hearts, the decreased dP/dtmax and load-independent contractility parameters were significantly increased after Q50. However, Q50 treatment did not reduce infarct size or have any effect on increased plasma cardiac troponin-T-levels. In the rat model of heart transplantation, 1h after reperfusion, decreased left ventricular systolic pressure, dP/dtmax, dP/dtmin and myocardial ATP content were significantly increased and myocardial protein expression of superoxide dismutase-1 was upregulated after Q50 treatment. Conclusions: In 2 experimental models of I/R, administration of Q50 improved myocardial function. Its mechanisms of action implicate in part the restoration of myocardial high-energy phosphates and upregulation of antioxidant enzymes.  (Circ J 2013; 77: 1817–1826

Highly regioselective 4-hydroxy-1-methylpiperidine mediated aromatic nucleophilic substitution on a perfluorinated phthalimide core

A tertiary amine-mediated highly regioselective aromatic nucleophilic substitution (SNAr) protocol was developed in the assemblies of perfluorinated phtalimide with primary or secondary amines as inputs. Application of 1-methyl-4-hydroxypiperidine as additive, formation of the less favoured, bioactive regioisomer was facilitated, modifying their ratios from the initial 8–36% to 81–91%. After optimization, a facile gram scale syntheses were accomplished and isolated the desired analogues in up to 63% yield. © 201

Facile synthesis of 1H-imidazo[1,2-b]pyrazoles via a sequential one-pot synthetic approach

5-Aminopyrazole-4-carbonitrile and ethyl 5-aminopyrazole-4-carboxylate, as potential trifunctional building blocks are introduced in a facile, chemo- and regioselective multicomponent assembly of imidazo[1,2-b]pyrazoles via the Groebke–Blackburn–Bienaymé reaction (GBB reaction). Besides the synthetic elaboration of a green-compatible isocyanide-based access in three-component mode, we describe an operationally simple, one-pot two-step GBB protocol for the rapid construction of a 46 membered imidazo[1,2-b]pyrazole library with yields up to 83%