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BackgroundIndigo naturalis (IN) is an herbal medicine that has been used for ulcerative colitis with an unclear mechanism of action. Indigo and indirubin, its main constituents, are ligands of the aryl hydrocarbon receptor (AhR). We assessed the safety, efficacy, and colon AhR activity of IN given orally to patients with treatment-refractory ulcerative colitis. The role of AhR in IN benefit was further evaluated with an AhR antagonist in a murine colitis model.MethodsThis open-label, dose-escalation study sequentially treated 11 patients with ulcerative colitis with either IN 500 mg/day or 1.5 g/day for 8 weeks, followed by a 4-week non-treatment period. The primary efficacy endpoint was clinical response at week 8, assessed by total Mayo score. Secondary endpoints included clinical remission, Ulcerative Colitis Endoscopic Index of Severity, quality of life, and colon AhR activity measured by cytochrome P450 1A1 (CYP1A1) RNA expression.ResultsTen of 11 (91%) patients, including 8/9 (89%) with moderate-to-severe disease, achieved a clinical response. Among these 10 patients, all had failed treatment with 5-aminosalicylic acid, 8 patients with a tumour necrosis factor (TNF)-alpha inhibitor, and 6 patients with TNF-alpha inhibitor and vedolizumab. Five patients were corticosteroid dependent. Clinical response was observed in all five patients who had been recommended for colectomy. Three patients achieved clinical remission. All patients experienced improved endoscopic severity and quality of life. Four weeks after treatment completion, six patients had worsened partial Mayo scores. Four patients progressed to colectomy after study completion. Colon CYP1A1 RNA expression increased 12 557-fold at week 8 among six patients evaluated. No patient discontinued IN due to an adverse event. Concomitant administration of 3-methoxy-4-nitroflavone, an AhR antagonist, in a murine colitis model abrogated the benefit of IN.ConclusionIN is a potentially effective therapy for patients with treatment-refractory ulcerative colitis. This benefit is likely through AhR activation.Trial registration numberNCT02442960.

Chronic intestinal inflammation accompanies familial adenomatous polyposis (FAP) and is a major risk factor for colorectal cancer in patients with this disease, but the cause of such inflammation is unknown. Because retinoic acid (RA) plays a critical role in maintaining immune homeostasis in the intestine, we hypothesized that altered RA metabolism contributes to inflammation and tumorigenesis in FAP. To assess this hypothesis, we analyzed RA metabolism in the intestines of patients with FAP as well as APCMin/+ mice, a model that recapitulates FAP in most respects. We also investigated the impact of intestinal RA repletion and depletion on tumorigenesis and inflammation in APCMin/+ mice. Tumors from both FAP patients and APCMin/+ mice displayed striking alterations in RA metabolism that resulted in reduced intestinal RA. APCMin/+ mice placed on a vitamin A-deficient diet exhibited further reductions in intestinal RA with concomitant increases in inflammation and tumor burden. Conversely, restoration of RA by pharmacologic blockade of the RA-catabolizing enzyme CYP26A1 attenuated inflammation and diminished tumor burden. To investigate the effect of RA deficiency on the gut immune system, we studied lamina propria dendritic cells (LPDC) because these cells play a central role in promoting tolerance. APCMin/+ LPDCs preferentially induced Th17 cells, but reverted to inducing Tregs following restoration of intestinal RA in vivo or direct treatment of LPDCs with RA in vitro These findings demonstrate the importance of intestinal RA deficiency in tumorigenesis and suggest that pharmacologic repletion of RA could reduce tumorigenesis in FAP patients. Cancer Immunol Res; 4(11); 917-26. ©2016 AACR.

Whereas cancers grow within host tissues and evade host immunity through immune-editing and immunosuppression, tumours are rarely transmissible between individuals. Much like transplanted allogeneic organs, allogeneic tumours are reliably rejected by host T cells, even when the tumour and host share the same major histocompatibility complex alleles, the most potent determinants of transplant rejection. How such tumour-eradicating immunity is initiated remains unknown, although elucidating this process could provide the basis for inducing similar responses against naturally arising tumours. Here we find that allogeneic tumour rejection is initiated in mice by naturally occurring tumour-binding IgG antibodies, which enable dendritic cells (DCs) to internalize tumour antigens and subsequently activate tumour-reactive T cells. We exploited this mechanism to treat autologous and autochthonous tumours successfully. Either systemic administration of DCs loaded with allogeneic-IgG-coated tumour cells or intratumoral injection of allogeneic IgG in combination with DC stimuli induced potent T-cell-mediated antitumour immune responses, resulting in tumour eradication in mouse models of melanoma, pancreas, lung and breast cancer. Moreover, this strategy led to eradication of distant tumours and metastases, as well as the injected primary tumours. To assess the clinical relevance of these findings, we studied antibodies and cells from patients with lung cancer. T cells from these patients responded vigorously to autologous tumour antigens after culture with allogeneic-IgG-loaded DCs, recapitulating our findings in mice. These results reveal that tumour-binding allogeneic IgG can induce powerful antitumour immunity that can be exploited for cancer immunotherapy.

Scalable processes have been developed to convert β‐pinene into 4‐isopropenylcyclohexanone, which is then used as a feedstock for the divergent synthesis of sustainable versions of the common painkillers, paracetamol and ibuprofen. Both synthetic routes use Pd0 catalysed reactions to aromatize the cyclohexenyl rings of key intermediates to produce the benzenoid ring systems of both drugs. The potential of using bioderived 4‐hydroxyacetophenone as a drop‐in feedstock replacement to produce sustainable aromatic products is also discussed within a terpene biorefinery context. [ABSTRACT FROM AUTHOR]

Phosphorus-31 and carbon-13 CPMAS NMR spectra have been obtained for imino(triphenyl)phosphorane and amino(triphenyl)phosphonium bromide. Detailed analysis yields information about the 31P shielding tensor and the 14N quadrupole coupling tensor. The static 31P spectrum of the bromide was also analysed in terms of the relevant tensors. Ab initio calculations at the hf/6-31g* level reproduce the observed data well, except for the isotropic shifts, which require a larger basis set and/or higher level of theory. The orientations of the tensors in the molecular frame are derived for the bromide from the calculations.

Chronic inflammation characterized by T cell and macrophage infiltration of visceral adipose tissue (VAT) is a hallmark of obesity-associated insulin resistance and glucose intolerance. Here we show a fundamental pathogenic role for B cells in the development of these metabolic abnormalities. B cells accumulate in VAT in diet-induced obese (DIO) mice, and DIO mice lacking B cells are protected from disease despite weight gain. B cell effects on glucose metabolism are mechanistically linked to the activation of proinflammatory macrophages and T cells and to the production of pathogenic IgG antibodies. Treatment with a B cell-depleting CD20 antibody attenuates disease, whereas transfer of IgG from DIO mice rapidly induces insulin resistance and glucose intolerance. Moreover, insulin resistance in obese humans is associated with a unique profile of IgG autoantibodies. These results establish the importance of B cells and adaptive immunity in insulin resistance and suggest new diagnostic and therapeutic modalities for managing the disease., Obesity and its associated metabolic abnormalities, including insulin resistance and type 2 diabetes, have reached epidemic proportions, adversely affecting health and global mortality rates (1). Multiple factors contribute to reduced [...]

FlowNMR spectroscopy has become a popular and powerful technique for online reaction monitoring. DOSY NMR is an established technique for obtaining information about diffusion rates and molecular size on static samples. This work extends the FlowNMR toolbox to include FlowDOSY based on convection compensation and use of a low-pulsation pump or flow effect correction, allowing accurate and precise diffusion coefficients to be obtained at flow rates up to 4.0 mL min−1 in less than 5 minutes. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of seven new titanium catechol-based complexes are reported. The results have shown that a coordinated 2-propanol is observed in all the structures, which is involved in hydrogen bonding to one of the isopropoxide ligands, and the complexes are screened for the ring-opening polymerization (ROP) of epsilon-caprolactone at room temperature.

ZnII‐complexes bearing half‐salan ligands were exploited in the mild and selective chemical upcycling of various commercial polyesters and polycarbonates. Remarkably, we report the first example of discrete metal‐mediated poly(bisphenol A carbonate) (BPA‐PC) methanolysis being appreciably active at room temperature. Indeed, Zn(2)2 and Zn(2)Et achieved complete BPA‐PC consumption within 12–18 mins in 2‐Me‐THF, noting high bisphenol A (BPA) yields (SBPA=85–91 %) within 2–4 h. Further kinetic analysis found such catalysts to possess kapp values of 0.28±0.040 and 0.47±0.049 min−1 respectively at 4 wt%, the highest reported to date. A completely circular upcycling approach to plastic waste was demonstrated through the production of several renewable poly(ester‐amide)s (PEAs), based on a terephthalamide monomer derived from bottle‐grade poly(ethylene terephthalate) (PET), which exhibited excellent thermal properties. [ABSTRACT FROM AUTHOR]

A cationic aminophenoxy-aluminium compound has been synthesized and its solid-state structure analyzed. Four H2salen aluminium derivatives have also been synthesized and structurally analyzed. The derivatives have varying counterions. Dimer formation via weak NH hydrogen bonded Cl- ions is found in three of the compounds. Ionic lattice-type structures are found in the rest.

The chemical industry is increasingly looking to develop bio-based alternatives to petroleum-based platform chemicals, in order to reduce dependence on diminishing fossil resources and to decrease GHG emissions. 5-Hydroxymethylfurfural (HMF) and 2,5-furandicarboxylic acid (FDCA) are two examples of bio-based chemicals which could allow for the synthesis of a wide range of chemicals and materials, particularly polymers, from renewable feedstocks. This review paper summarises and critically evaluates results from existing life cycle assessment (LCA) and technoeconomic analysis (TEA) studies of HMF and FDCA synthesis and, by doing this, provides several points of advice for future investigations and assessments of synthetic routes towards these bio-based products. Chemical considerations such as choice of solvent system, catalyst and energy production are reviewed; and methodological issues in LCA, such as treatment of biogenic carbon and allocation methods, are discussed. Overall, results suggest that the production of HMF and FDCA-based products may offer lower impacts from CO2 emissions than their fossil-based counterparts, but this often comes with an increase in environmental impacts in other impact categories. Higher operating costs from expensive fructose feedstocks and high energy demands also make HMF and FDCA less economically viable than current chemicals. Moving forwards, further investigation into different lignocellulosic feedstocks, energy production units and the development of new catalytic systems may help in making HMF and FDCA production more favourable than the production of fossil-based counterparts. [ABSTRACT FROM AUTHOR]

The use of a simple, cheap and effective organocatalyst, tetramethylammonium methyl carbonate, has been exploited for the transesterification of a range of commercial polymer samples. PLA, PCL, PC and PET have been successfully broken down into useful products, with the repolymerisation of DMT to PET demonstrated, highlighting a truly circular economy approach. [ABSTRACT FROM AUTHOR]

The selective catalytic synthesis of limonene‐derived monofunctional cyclic carbonates and their subsequent functionalisation via thiol–ene addition and amine ring‐opening is reported. A phosphotungstate polyoxometalate catalyst used for limonene epoxidation in the 1,2‐position is shown to also be active in cyclic carbonate synthesis, allowing a two‐step, one‐pot synthesis without intermittent epoxide isolation. When used in conjunction with a classical halide catalyst, the polyoxometalate increased the rate of carbonation in a synergistic double‐activation of both substrates. The cis isomer is shown to be responsible for incomplete conversion and by‐product formation in commercial mixtures of 1,2‐limomene oxide. Carbonation of 8,9‐limonene epoxide furnished the 8,9‐limonene carbonate for the first time. Both cyclic carbonates underwent thiol–ene addition reactions to yield linked di‐monocarbonates, which can be used in linear non‐isocyanate polyurethanes synthesis, as shown by their facile ring‐opening with N‐hexylamine. Thus, the selective catalytic route to monofunctional limonene carbonates gives straightforward access to monomers for novel bio‐based polymers. [ABSTRACT FROM AUTHOR]

A stereoselective, solvent-free ring-opening polymerisation (ROP) of lactide (LA) in supercritical carbon dioxide (scCO2) is reported for the first time. The key aim is to exploit scCO2 to lower the temperature of traditional melt polymerisations, lowering the energy requirement and leading to cleaner polymeric materials. We have utilised a zirconium amine-trisphenolate initiator-stereoselective catalyst [(iPrO)Zr(OPh(tBu)2-CH2)3N] to yield highly heterotactic poly(lactide) (PLA) homopolymer (Pr = 0.74–0.84) from rac-LA, demonstrating control of the PLA microstructure in scCO2. In addition, high monomer conversion (86–93%) was achieved in short reaction time (1 h), affording poly(lactide) with a very low degree of transesterification and narrow molecular weight distribution. Most importantly, all the reactions were performed at only 80 °C, almost 100 °C lower than the conventional melt process (typically performed at 130–180 °C), representing a very significant potential energy saving. [ABSTRACT FROM AUTHOR]

A tungsten-based polyoxometalate catalyst employing aqueous H2O2 as a benign oxidant has been used for the solvent free catalytic epoxidation of the trisubstituted alkene bonds of a wide range of biorenewable terpene substrates. This epoxidation protocol has been scaled up to produce limonene oxide, 3-carene oxide and α-pinene oxide on a multigram scale, with the catalyst being recycled three times to produce 3-carene oxide. Epoxidation of the less reactive disubstituted alkene bonds of terpene substrates could be achieved by carrying out catalytic epoxidation reactions at 50 °C. Methods have been developed that enable direct epoxidation of untreated crude sulfate turpentine to afford 3-carene oxide, α-pinene oxide and β-pinene oxide. Treatment of crude epoxide products (no work-up) with a heterogeneous acid catalyst (Amberlyst-15) results in clean epoxide hydrolysis to afford their corresponding terpene-anti-diols in good yields. [ABSTRACT FROM AUTHOR]

The bis-guanidino compound [H.sub.2]C[{hpp}.sub.2] (hppH = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine) is converted to the monocation and isolated as the chloride and tetraphenylborate salts. Triadic analysis has shown that the dominant term causing the high basicity is the relaxation energy.

The analysis describes the synthesis, characterization and the structure of a molecular trinuclear barium aminebis(phenolate) complex. The results show that the complex can be easily used as an initiator for the ring-opening polymerization of several cyclic esters.

An air-stable titanium-organic framework, prepared from Ti(OPr)4 and 1,4-butanediol, is characterized through single-crystal X-ray diffraction, revealing a unique supermolecular structure. Its functionality as a high active initiator for the ring-opening polymerization of cyclic esters is also demonstrated.

The application of aminetris(phenoxide) ligands to Bi and Sb chemistry, resulting in the structural characterization of an isolated Bi 'inverted-sandwich' complex, which is well-defined and hydrocarbon-soluble, is reported. The density functional theory calculations of the sandwich bismuth arene complex have indicated the presence of a weak sigma*-2pi interaction.

The chiral fluorescent sensor was found to be highly sensitive, chemeoselective and enantioselective to sugar acids, such as tartic acid, glucaric acid, and gluconic acid. The results and the unambiguous structural data could be useful for the development and application of enantioselective chemical sensors.

A new way to combine two different polymerisation reactions, using a single catalyst, results in efficient block polymer synthesis. The selective polymerisation of mixtures of l-lactide-O-carboxyanhydride and cyclohexene oxide, using a di-zinc catalyst in a one-pot procedure, allows the preparation of poly(l-lactide-b-cyclohexene carbonate). The catalysis near quantitatively recycles the carbon dioxide released during polyester formation into the subsequent polycarbonate block, with an atom economy of up to of 91%. [ABSTRACT FROM AUTHOR]

A range of ligands based upon 2-(aminomethyl)piperidine have been successfully complexed to Mg(ii), Zn(ii) and group IV metal centres. These complexes have been characterised both in solution and solid state with different coordination geometries realised dependant on the nature of the ligand. For the Mg(ii) and Zn(ii) complexes, M(1–2)2, were isolated and analysed by DOSY NMR spectroscopy. These ligands also furnished diastereomeric group IV complexes, M(1–2)2(OiPr)2. Group IV salalen and salan complexes, M(4–5)(OR)2 were also found to be diastereomeric in nature, with either β-cis or α-cis geometriesrespectively. The tridentate ligand, 6H2, yielded five coordinate complexes with both Ti(iv) and Zr(iv). All complexes were screened for the ring opening polymerisation of rac-lactide under both solvent and melt conditions. For the Mg(ii) and Zn(ii) complexes, good activity was observed with Zn(1–2)2 demonstrating immortal polymerisation characteristics. [ABSTRACT FROM AUTHOR]