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Structurally diverse novel 1,4-benzodiazepine analogues related to selective CCKA antagonist MK-329, and CCKB antagonists L-365,260 and YM022 are prepared via palladium-catalyzed three component domino reactions involving allenylation-carbonylation-anion capture in one-pot cascade protocol in good to excellent yields. The authors thank Mersin University (Turkey), The University of Leeds (UK), and the University of Alicante for support. We also thank the Scientific and Technological Research Council of Turkey (TÜB_ITAK), the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P and CTQ2014-51912-REDC), the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P, and CTQ2016-81797-REDC), the Generalitat Valenciana (PROMETEOII/2014/017), (Consolider Ingenio 2010, CSD2007-00006) for research financing.

γ-Carbolines were prepared from pyrido[4,3- b ]-5 H -indoles via Pd(0)-catalysed, stereo and regioselective allene/uridine allene insertion 3- and 5-component cascades. This versatile reaction sequence gives a range of structurally diverse carboline derivatives and tolerates a broad range of substrates. The power of this approach has been harnessed to produce γ-carboline based HDAC inhibitors.

Histone deacetylase (HDAC) inhibitors prevent neural cell death in in vivo models of cerebral ischaemia, brain injury and neurodegenerative disease. One mechanism by which HDAC inhibitors may do this is by suppressing the excessive inflammatory response of chronically activated microglia. However, the molecular mechanisms underlying this anti-inflammatory effect and the specific HDAC responsible are not fully understood. Recent data from in vivo rodent studies have shown that inhibition of class I HDACs suppresses neuroinflammation and is neuroprotective. In our study, we have identified that selective HDAC inhibition with inhibitors apicidin, MS-275 or MI-192, or specific knockdown of HDAC1 or 2 using siRNA, suppresses the expression of cytokines interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) in BV-2 murine microglia activated with lipopolysaccharide (LPS). Furthermore, we found that in the absence of HDAC1, HDAC2 is up-regulated and these increased levels are compensatory, suggesting that these two HDACs have redundancy in regulating the inflammatory response of microglia. Investigating the possible underlying anti-inflammatory mechanisms suggests an increase in protein expression is not important. Taken together, this study supports the idea that inhibitors selective towards HDAC1 or HDAC2, may be therapeutically useful for targeting neuroinflammation in brain injuries and neurodegenerative disease.

Histone deacetylase (HDAC) inhibitors prevent neural cell death in in vivo models of cerebral ischaemia, brain injury and neurodegenerative disease. One mechanism by which HDAC inhibitors may do this is by suppressing the excessive inflammatory response of chronically activated microglia. However, the molecular mechanisms underlying this anti-inflammatory effect and the specific HDAC responsible are not fully understood. Recent data from in vivo rodent studies has shown that inhibition of class I HDACs suppresses neuroinflammation and is neuroprotective. In our study we have identified that selective HDAC inhibition with inhibitors apicidin, MS-275 or MI-192, or specific knockdown of HDAC1 or 2 using siRNA, suppresses the expression of cytokines interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) in BV2 murine microglia activated with lipopolysaccharide (LPS). Furthermore, we found that in the absence of HDAC1, HDAC2 is upregulated and these increased levels are compensatory, suggesting these two HDACs have redundancy in regulating the inflammatory response of microglia. Investigating the possible underlying anti-inflammatory mechanisms suggests an increase in protein expression is not important. Taken together, this study supports the idea that inhibitors selective towards HDAC1 or HDAC2, may be therapeutically useful for targeting neuroinflammation in brain injuries and neurodegenerative disease.Significance StatementThe number of patients suffering a stroke or a neurodegenerative disease, such as Alzheimer’s is increasing These conditions are severely debilitating and are leading causes of mortality, with neural cell death and loss of brain tissue being a major feature. A number of mechanisms contribute to neuronal death, including inflammation in the brain, but we still lack clinical therapies to inhibit this. The work presented here provides further insight into potential molecular therapeutic targets called histone deacetylases (HDACs), which are thought to contribute to neural cell death by promoting inflammation. We show that down regulation of HDAC1 and 2 is sufficient to reduce this inflammatory response. Our findings have clinical relevance because they identify HDAC1 and 2 as promising targets for therapy.

INTRODUCTION: High-grade gliomas feature prominently among the most devastating cancers due to their prevalence in the younger population, highly invasive nature and low 5-year survival. Despite a combined treatment regime of surgical resection, radiation therapy and chemotherapy most patients die within 1 year of initial diagnosis. Alternative, novel ways to treat these tumours are urgently required. Histone deacetylase (HDAC) are important regulators of chromatin remodelling and gene expression and have been shown to be involved in cancer. There is an increasing interest in the study and development of HDAC inhibitors towards clinical application. Moreover, they have been recently reported to inhibit cell migration due to their modulation of tubulin acetylation. Thus HDAC inhibitors represent attractive candidates for chemotherapeutics especially when considering the infiltrative nature of high-grade gliomas. Here, the specific HDAC2/3 inhibitor MI192 developed at Leeds University was investigated for its ability to inhibit 2D and 3D migration of two established adult glioma cell lines. METHODS: U87 and U251 cell lines were used for migration and cytoskeletal studies in 2D and 3D assays. The HDAC inhibitor MI192 was assessed for its ability to inhibit migration alongside LiCl and Bio-Indirubin, two anti-migratory drugs commonly used in glioma in vitro studies. RESULTS: In random migration (2D) the MI192 inhibitor adversely affected the migratory ability of U87 and U251 as evidenced by reduced cell velocity and also cell displacement. This effect was more pronounced in U251 than U87. Immunofluorescence studies of the MI192-treated cells revealed an increase in the acetylation of tubulin in U87, whilst proliferation and apoptosis status remained unchanged. U251 did not appear to show increased levels of tubulin acetylation. In a 3D spheroid invasion assay U87 migration was inhibited by MI192 at 1 uM concentration, but not at 0.1 or 0.01 uM, whereas we did not see a significant change in U251. Immunohistochemistry of the treated spheroids revealed that proliferation was adversely affected in both the core and migratory cells in U87 spheroids with MI192 at a concentration of 1 uM but not in U251 spheroids. Tubulin acetylation appeared more pronounced in U251 after MI192 treatment. In addition, SOX-2 (as a marker of stemness) was reduced in both U251 cores and migratory cells with MI192. CONCLUSION: In addition to its activity as a chromatin remodelling inhibitor, MI192 appears to inhibit glioma cell migration via hyperacetylation of tubulin and possibly microtubule stabilisation in a cell line and topography dependent manner. Thus, the HDAC2/3 inhibitor MI192 may prove useful in targeting migration in certain subtypes of glioma cell.

Bazedoxifene (BZA) is a third-generation selective estrogen receptor modulator (SERM) that has been approved for the prevention and treatment of postmenopausal osteoporosis. It has antitumor activity; however, its mechanism of action remains unclear. In the present study, we characterized the effects of BZA and several other SERMs on the proliferation of hormone-dependent MCF-7 and T47D breast cancer cells and hormone-independent MCF-7:5C and MCF-7:2A cells and examined its mechanism of action in these cells. We found that all of the SERMs inhibited the growth of MCF-7, T47D, and MCF-7:2A cells; however, only BZA and fulvestrant (FUL) inhibited the growth of hormone-independent MCF-7:5C cells. Cell cycle analysis revealed that BZA and FUL induced G(1) blockade in MCF-7:5C cells; however, BZA down-regulated cyclin D1, which was constitutively overexpressed in these cells, whereas FUL suppressed cyclin A. Further analysis revealed that small interfering RNA knockdown of cyclin D1 reduced the basal growth of MCF-7:5C cells, and it blocked the ability of BZA to induce G(1) arrest in these cells. BZA also down-regulated estrogen receptor-α (ERα) protein by increasing its degradation and suppressing cyclin D1 promoter activity in MCF-7:5C cells. Finally, molecular modeling studies demonstrated that BZA bound to ERα in an orientation similar to raloxifene; however, a number of residues adopted different conformations in the induced-fit docking poses compared with the experimental structure of ERα-raloxifene. Together, these findings indicate that BZA is distinct from other SERMs in its ability to inhibit hormone-independent breast cancer cell growth and to regulate ERα and cyclin D1 expression in resistant cells.

A palladium-catalyzed three-component cascade process for the synthesis of isoindolone and phthalazone derivatives is reported. The cascade process involves carbonylation of an aryl iodide/Michael acceptor to give an acylpalladium species which is intercepted by a hydrazine nucleophile. Intramolecular Michael addition follows to give either N-aminoisoindolones or mono- N- and di-N,N'-phthalazones depending on whether a monosubstituted or 1,2-disubstituted hydrazine nucleophile is used.

1,3-Dipolar reactions of imines of both acyclic and cyclic α-amino esters with a range of nitroolefins using a combination of AgOAc or Ag2O with NEt3 are described. In most cases the reactions were highly regio- and stereospecific and endo-cycloadducts were obtained in good yield. However, in a few cases the initially formed cycloadducts underwent base catalysed epimerisation. The stereochemistry of the cycloadducts was assigned from NOE data and established unequivocally in several cases by X-ray crystallography.\ud \ud

Histone deacetylase 3 removes acetyl groups from lysine residues, thereby modifying protein function. It is found in both the nucleus and the cytoplasm. We have discovered that it can indirectly deacetylate tubulin, a cytoplasmic protein that forms microtubules, thus modifying the microtubule., Histone deacetylase 3 (HDAC3), a member of the Class I subfamily of HDACs, is found in both the nucleus and the cytoplasm. Its roles in the nucleus have been well characterized, but its cytoplasmic roles are still not elucidated fully. We found that blocking HDAC3 activity using MI192, a compound specific for HDAC3, modulated tubulin acetylation in the human prostate cancer cell line PC3. A brief 1 h treatment of PC3 cells with MI192 significantly increased levels of tubulin acetylation and ablated the dynamic behaviour of microtubules in live cells. siRNA-mediated knockdown (KD) of HDAC3 in PC3 cells, significantly increased levels of tubulin acetylation, and overexpression reduced it. However, the active HDAC3–silencing mediator of retinoic and thyroid receptors (SMRT)–deacetylase-activating domain (DAD) complex did not directly deacetylate tubulin in vitro. These data suggest that HDAC3 indirectly modulates tubulin acetylation.

A new series of Rh, Ir and Ru precatalysts for the [2+2+2] cyclotrimerisation of 1,6-diynes with monoynes is reported. The precatalysts are reduced in situ to the active catalysts by reduction with alcohols. The precatalysts activity is in the order Ru>Rh>Ir which reflects the ease of this reduction. The Rh and Ir precatalysts require temperature in excess of 140 C allowing their preparation in 2-methoxymethanol at 125 C. The mechanism of this process is discussed.

Purpose: Selective estrogen receptor modulators (SERM) are used for the treatment and prevention of breast cancer (tamoxifen) and osteoporosis (raloxifene). Mechanisms of tamoxifen-resistance in breast cancer are incompletely understood but current research is focused on crosstalk between growth factor receptors and the estrogen receptor α (ERα) pathway. There is increasing clinical use of raloxifene for the treatment of osteoporosis, but the widespread use of this SERM will have consequences for the treatment of breast cancer in raloxifene-exposed women. Experimental Design: We took the strategic step of developing a raloxifene-resistant tumor (MCF-7RALT) model in vivo and investigating the mechanisms responsible for resistance. Results: MCF-7RALT tumors exhibited phase I SERM resistance, growing in response to SERMs and 17β-estradiol. Epidermal growth factor receptor/HER1 and HER2/neu mRNAs were increased in MCF-7RALT tumors. The HER2/neu blocker, trastuzumab, but not the epidermal growth factor receptor blocker, gefitinib, decreased the growth of MCF-7RALT tumors in vivo. Consequently, trastuzumab decreased prosurvival/proliferative proteins: phospho-HER2/neu, total HER2/neu, phospho-Akt (protein kinase B), glycogen synthetase kinase-3, cyclin D1, and the antiapoptotic protein X chromosome-linked inhibitor of apoptosis, whereas increasing the proapoptotic protein, caspase-7, in raloxifene-treated MCF-7RALT tumors. Interestingly, ERα protein was overexpressed in untreated MCF-7RALT tumors and hyperactivated in cells derived from these tumors. Only fulvestrant completely inhibited the growth and ERα activity of MCF-7RALT tumors. The coactivator of ERα, amplified in breast cancer-1 protein was modestly increased in the raloxifene-treated MCF-7RALT tumors and increased both basal and estradiol-induced activity of ERα in cells derived from the MCF-7RALT tumors. Conclusions: These results suggest that overexpression and increased activity of HER2/neu might be responsible for the development of raloxifene-resistant breast cancer. The results also suggest that increased expression of basal activity of ERα could contribute to the hypersensitivity of MCF-7RALT tumors in response to estradiol because only fulvestrant blocked growth and ERα activity.

A sequential one-pot process is reported involving in situ, palladium catalysed, formation of a series of tributylstannyl-1,2-carbo and heterocyclic dialkylidene-5-membered rings from the corresponding 1,6-diynes and Bu 3 SnH. These substrates and other organostannanes are then combined with carbamyl chlorides and iodobenzenes containing proximate alkene and alkynyl groups in palladium catalysed cyclisation–anion capture cascades affording a diverse range of heterocycles in good yield.

Treatment of PdCys or palladium salts with carbon monoxide (1 atm) in DMF or toluene at room temperature results in a solution of palladium nanoparticles whose morphology depends on the PdCy or palladium salt. Unusual triangular shaped 2–12 nm nanoparticles result from PdCys 1 and 3.

A new general three-component Pd/In bimetallic cascade reaction with four synthetic variants involving aryl iodides, allenes and C=X compounds affording homoallylic alcohols/amines as products is described and exemplified for Class 1 processes (intermolecular Pd–intermolecular In steps). Remarkable increases in yield and reaction rates were observed in the presence of amine additives. Excellent diastereoselection is exhibited when 2-hydroxycyclohexanone is employed, and semi-empirical and ab initio calculations are used to rationalise the observed syn : anti diastereoselectivity.

Cyclic carbopalladation can be achieved by a group of related reactions that provide versatile and powerful methodology for the construction of carbocyclic and heterocyclic rings. These ring forming processes are marked by their tolerance of a wide range of functionality together with their ability to process a variety of starter species and to effect cyclisation onto all types of C–C unsaturated bonds. Substantial additional pre- and post-cyclisation functionality can be incorporated via cyclisation-anion capture and/or polycomponent cascades that switch between inter- and intra-molecular processes. The polycomponent cascades can be regarded as proceeding via molecular queuing processes and when gaseous reactants are employed the queuing processes are sensitive to pressure. These wide ranging processes occur with excellent chemo-, regio- and stereo-selectivity and allow incorporation of precisely located complex functionality whilst generating bridged, fused and spirocyclic systems and multiple C–C/C-heteroatom bonds.

Pd(0) catalysts facilitate the assembly of complex heterocycles and carbocycles containing 3 - 7 membered rings from a range of simple building blocks (allenes, carbon monoxide, alkenes, organometallic complexes of B, Zn, Sn etc.). These cascade processes display remarkable chemo-, regio- and stereo-selectivity and considerably extend the scope and utility of our previously developed cyclisation-anion capture cascades. The success of these processes is critically dependant on the relative rates of a range of potentially competing processes and the various substrates can be regarded as queuing for access to the catalytic metal centre. Certain compounds are identified as relay switches because they extend the relay phase of the cyclisation-anion capture cascade whilst allowing the Pd catalysed cascades to switch between inter- and intra-molecular processes. Palladium salts and complexes are exceptionally versatile catalysts for the construction of carbon-carbon and carbon-heteroatom bonds.' Much recent attention has focused on the Heck reaction2 (Scheme 1) due to developments which have considerably enhanced the scope of this palladium-catalysed vinylation of aryl, heteroaryl, vinyl and benzyl halides. Thus the Heck reaction has been extended to the synthesis of bridged rings, spirocycles, and tetrasubstituted carbon centre^.^-^ These latter developments and the ongoing high level of activity have been further fostered by the advent of a range of additives which variously enhance the rate of Heck reactions, control the rkgioselectivity of the P-hydride elimination step, and suppress double bond isomerisation in the product. Thus addition of tetraalkylammonium salts often allow Heck reactions to be carried out at, or near, room temperature in good yield,6 whilst addition of Ag(1) salts' or Tl(I)* salts can control the direction of P-hydride elimination, suppress double bond isomerisation and influence the reaction rate. Tl(1) additives have also proved useful in natural product synthesis.' However, the Heck reaction fails to take advantage of the inherent ability of palladium (0) catalysts to process a wide range of chemically distinctive substrates and suffers from the drawback that, as usually practised, only one C-C bond is made.

Objective To characterize the role of histone deacetylase (HDAC) activity in rheumatoid arthritis (RA) and to evaluate the effects of MI192, a novel HDAC-3–selective inhibitor, compared with the established nonselective HDAC inhibitor trichostatin A (TSA), on proinflammatory cytokine production. Methods Activity of HDAC and histone acetyltransferase was measured in peripheral blood mononuclear cells (PBMCs) from RA patients by spectrophotometric assay, prior to and after 12 weeks of etanercept therapy. The effects of HDAC inhibitor treatment on cytokine production in both RA and healthy PBMCs were assessed by enzyme-linked immunosorbent assay. Results RA PBMCs exhibited significantly increased HDAC activity (P = 0.007) compared to PBMCs from healthy individuals, and the increase was unaltered after 12 weeks of etanercept therapy. TSA was a potent inhibitor of tumor necrosis factor (TNF) and interleukin-6 (IL-6) production in both RA and healthy PBMCs and of interferon-γ (IFNγ) production in healthy PBMCs; IFNγ was not produced by RA PBMCs. MI192 inhibited TNF production at high concentrations and dose-dependently inhibited IL-6 in RA PBMCs but not healthy PBMCs, across a dose range of 10 μM–5 nM. Conclusion HDAC activity is dysregulated in RA PBMCs and is a potential target for therapeutic intervention, as it is not affected by conventional anti-TNF treatment with etanercept. Both the selective and the nonselective HDAC inhibitors (MI192 and TSA, respectively) were found to regulate cytokine production from PBMCs, but their effects were cell type and compound specific. HDAC inhibitors have potential in the treatment of RA, and HDAC-selective inhibition may improve the therapeutic margin of safety; however, further clinical characterization and evaluation for adverse effects is needed.

Stereoselective cyclo-addition reactions of azomethine ylides promoted by in situ generated Ag(I)/bisphosphine complexes were studied. Under the optimized conditions, the pyrrolidine products were isolated in up to 84 % yield and with up to 71% e.e. The effects of various reaction variables on the stereoselectivity were also investigated. Proučavane su stereoselektivne cikloadicione reakcije azometinskih ilida katalizovane kompleksima srebra i bisfosfinskog liganda generisanih in situ. Pirolidinski derivati izolovani su u dobrim prinosima i sa enantioselektivnošću do 71%. Proučavani su takođe i efekti reakcionih uslova na stereoselektivnost ovih reakcija.

Application of the Sonogashira reaction of N-alkynylimides with 2-iodophenol or 2-iodo-N-tosylaniline affords 2-(N-alkylimino)-benzofurans and indoles in good yield. Selective partial reduction of the latter followed by treatment with TsOH generates N-acyliminium ions, which cyclise to afford tetra- and pentacyclic lactams in good yield. The latter are reduced to the analogous cyclic amines by BH3.\ud \ud

A new, highly efficient synthesis of chiral beta(2.3)-disubstituted-beta-amino acid derivatives has been developed, based on an allylation procedure employing allene and a catalytic Pd/In bimetallic process.

Allylation of alpha,beta-unsaturated aldehydes and cyclic ketones promoted by Pd/In transmetallation processes has been Studied. The unsaturated aldehydes underwent regioselective 1,2-addition to afford secondary homoally alcohols. The reactions have been performed using Pd(OAc)(2)/PPh(3) as catalytic system and metallic indium affording the products in good yields. The same transformation with unsaturated ketones proved to be less efficient, while saturated cyclic ketones delivered generally excellent yields in the presence of Cul. In these latter processes the presence of a distal heteroatom influences the reaction rate.

The application of a ‘catch and release’ approach to palladium-catalysed multi-component cascade reactions leads to diverse libraries of pharmacologically interesting small molecules in high yield and with excellent purity. \ud \ud \ud \ud

Our objectives were to develop catalytic atom-economic processes accessing and/or incorporating versatile functionality using aryl/heteroaryl acetonitriles as substrates. We report essentially solvent-free [Cp*IrCl2]2 catalyzed redox neutral processes whereby substituted acetonitriles react with primary alcohols to deliver monosubstituted aryl/heteroaryl acetonitriles in excellent yield. We further demonstrate that such processes can be achieved by conventional or microwave heating and that bis- and tris-primary alcohols are also processed efficiently.