39903-76-9Relevant academic research and scientific papers
Catalytic homogeneous oxidation of monoterpenes and cyclooctene with hydrogen peroxide in the presence of sandwich-type tungstophosphates [M4(H2O)2(PW9O34)2]n?, M = CoII, MnII and FeIII
Santos, Isabel C.M.S.,Gamelas, José A.F.,Duarte, Tiago A.G.,Sim?es, Mário M.Q.,Neves, M. Gra?a P.M.S.,Cavaleiro, José A.S.,Cavaleiro, Ana M.V.
, p. 593 - 599 (2016/12/16)
Catalytic efficiency of tetrabutylammonium salts of sandwich tungstophosphates B‐α‐[M4(H2O)2(PW9O34)2]n?, M = CoII, MnII, FeIII, was studied in the oxidation of (R)-(+)-limonene, geraniol, linalool, linalyl acetate, carveol, and cis-cyclooctene with hydrogen peroxide, in acetonitrile. Oxidation of (R)-(+)-limonene gave limonene-1,2-diol as main product. Epoxidation of linalool takes place preferentially at the more substituted 6,7-double bond, the corresponding 6,7-epoxide reacting further, yielding furano- and pyrano-oxides, via intramolecular cyclization. Oxidation of linalyl acetate occurred preferentially at the more substituted 6,7-double bond for Mn4(PW9)2, affording 6,7-epoxide at 82% selectivity. Linalyl acetate 1,2-epoxide was the major product with 51% and 77% selectivity for Co4(PW9)2 and Fe4(PW9)2, respectively. Oxidation of carveol occurred with very good conversions in the presence of Mn4(PW9)2, Co4(PW9)2 and Fe4(PW9)2, yielding carvone and carveol 1,2-epoxide in similar amounts. Oxidation of cis-cyclooctene gave only the epoxide, while oxidation of geraniol at room temperature afforded 2,3-epoxygeraniol as the major product.
Grafted non-ordered niobium-silica materials: Versatile catalysts for the selective epoxidation of various unsaturated fine chemicals
Tiozzo, Cristina,Bisio, Chiara,Carniato, Fabio,Guidotti, Matteo
, p. 49 - 57 (2014/08/18)
Two kinds of niobium(V)-silica catalysts for the selective epoxidation were synthesised by post-synthesis modification of non-ordered mesoporous silica supports, starting from niobocene dichloride via solvent-less organometallic precursor dry impregnation
Catalytic performance of a boron peroxotungstate complex under homogeneous and heterogeneous conditions
Santos, Isabel C.M.S.,Balula, Salete S.,Sim?es, Mário M.Q.,Cunha-Silva, Luís,Neves, M. Gra?a P.M.S.,De Castro, Baltazar,Cavaleiro, Ana M.V.,Cavaleiro, José A.S.
, p. 87 - 94 (2013/08/24)
The preparation and characterization (FT-IR, FT-Raman, 11B MAS NMR, diffuse reflectance, elemental analysis) of a novel boron peroxotungstate (BTBA)4H[BW4O24] (BTBA = benzyltributylammonium) is reported, along with its use in the homogeneous oxidation of cis-cyclooctene, geraniol, linalool and (-)-carveol with H 2O2 as oxidant and acetonitrile as solvent. High catalytic activity was registered for all the substrates studied under homogeneous conditions, namely 99% of conversion of geraniol after 2 h, 93% for linalool after 5 h, 74% for cis-cyclooctene after 6 h, and 100% for (-)-carveol after 2 h of reaction. Some oxidation studies were carried out with the Venturello complex, [PW4O24]3-, in the same conditions. Furthermore, the boron peroxotungstate (BW4) was immobilized using two different strategies: (a) BW4 anchored into a functionalized silica (aptesSiO2) giving BW4@aptesSiO2 and (b) BW4 encapsulated on a metal organic framework, commonly referred as MIL-101, giving BW4@MIL-101. The catalytic activity of both heterogeneous materials was investigated for geraniol oxidation and the results were compared with those obtained with BW4 under homogeneous conditions. The encapsulated boron peroxotungstate (BW4@MIL-101) gave rise to the best results, reaching complete conversion of geraniol after 3 h of reaction and 78% selectivity for 2,3-epoxygeraniol. Additionally, this heterogeneous catalyst could be reused without appreciable loss of catalytic activity, affording similar 2,3-epoxygeraniol selectivity. The heterogeneous catalysts' stability was also investigated after the oxidation reactions by different characterization techniques.
Compounds which inhibit complement and/or suppress immune activity
-
, (2008/06/13)
The present invention is directed to compounds which suppress immune responses and/or selectively inhibit complement. These compounds contain an aromatic ring and are substituted dihydrobenzofurans, spirobenzofuran-2(3H)-cycloalkanes, and their open chain intermediates. The compounds of the present invention, and the phamaceutically acceptable salts thereof, interrupt the proteolytic processing of C5 to bioactive components, exhibit immunosuppressive activites, and have therapeutic utility in the amelioration of disease and disorders mediated by complement and/or immune activity.
