- Amino acid ionic liquids as catalysts in a solvent-free Morita-Baylis-Hillman reaction
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In the present work, we describe the preparation of ten amino acid ionic liquids (AAILs) formed from ammonium salts as cations, derivatives of glycerol, and natural amino acids as anions. All of them are viscous oils, colorless or pale yellow, and hygroscopic at room temperature. They have appreciable solubility in many protic and aprotic polar solvents. The AAILs were used as catalysts in a Morita-Baylis-Hillman (MBH) reaction. The ionic liquids derivative from l-proline and l-histidine demonstrated the ability to catalyze the reaction between methyl vinyl ketone and aromatic aldehydes differently substituted in the absence of an additional co-catalyst under organic solvent-free conditions. The AAIL derivatives from l-valine, l-leucine, and l-tyrosine catalyzed the MBH reaction only in the presence of imidazole. The MBH adducts were obtained in moderate to good yields. Although the catalytic site in the ILs was in its enantiomerically pure form, all the MBH adducts were obtained in their racemic form.
- Pereira, Mathias Prado,Souza Martins, Rafaela De,De Oliveira, Marcone Augusto Leal,Bombonato, Fernanda Irene
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p. 23903 - 23913
(2018/07/13)
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- A simple, novel method for the preparation of polymer-tetherable, zwitterionic merocyanine NLO-chromophores
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A suite of polymer-ready nonlinear optical merocyanines has been synthesised and characterised. The tethering functionality - a vicinal dihydroxypropyl residue - is introduced onto the donor nitrogen of the chromophore precursor without the need for protection/deprotection steps, thereby giving ready access to potentially high Tg condensation polymer systems. An X-ray crystal structure determination on a representative chromophore 5 confirms the largely zwitterionic nature of these systems and experimental measurements of second-order nonlinear response [β(0)], by hyper-Raleigh scattering, indicate that a pyridylidene donor-quinomethide acceptor combination gives rise to the largest nonlinearity.
- Kay,Woolhouse,Gainsford,Haskell,Barnes,McKinnie,Wyss
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p. 996 - 1002
(2007/10/03)
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- Pharmaceutical compositions containing 3-IODO-1,2-propanediol having mucolytic activity
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The present invention relates to pharmaceutical compositions containing 3-iodo-1,2-propanediol which are effective in increasing the output of thin respiratory tract fluid and liquefying tenacious mucus in the bronchial tree.
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- Antiestrogens and antiestrogen metabolites: Preparation of tritium-labeled (±)-cis-3-[p-(1,2,3,4-tetrahydro-6-methoxy-2-phenyl-1-naphthyl)phenoxy]-1,2-propanediol (U-23469) and characterization and synthesis of a biologically important metabolite
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The Upjohn antiestrogen (±)-cis-3-[p-(1,2,3,4-tetrahydro-6-methoxy-2-phenyl-1-naphthyl)phenoxy]-1,2-propanediol (2b, U 23469) has been prepared in tritium-labeled form by reduction of an unsaturated dihydronaphthalene precursor with carrier-free tritium gas over a palladium catalyst followed by alkylation with 3-iodo-1,2-propanediol. After extensive chromatographic purification, the final material was obtained with a specific activity of 13 Ci/mmol and a radiochemical purity of 94%. In vivo studies with immature rats show that [3H]2b is slowly converted to a more polar metabolite that is selectively accumulated in the nuclear fraction of the uterus where it is bound to the estrogen receptor. Chromatographic comparisons indicate that this metabolite is a demethylated analogue, a compound that has an affinity for estrogen receptor more than 300 times greater than that of 2b. These studies suggest that the demethylated analogue may be a biologically important metabolite of 2b that is involved in the action of this antiestrogen.
- Tatee,Carlson,Katzenellenbogen,Robertson,Katzenellenbogen
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p. 1509 - 1517
(2007/10/13)
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