1193-70-0Relevant academic research and scientific papers
Regioselective ketone α-alkylation with simple olefins via dual activation
Mo, Fanyang,Dong, Guangbin
, p. 68 - 72 (2014/07/21)
Alkylation of carbonyl compounds is a commonly used carbon-carbon bond-forming reaction. However, the conventional enolate alkylation approach remains problematic due to lack of regioselectivity, risk of overalkylation, and the need for strongly basic conditions and expensive alkyl halide reagents. Here, we describe development of a ketone-alkylation strategy using simple olefins as the alkylating agents. This strategy employs a bifunctional catalyst comprising a secondary amine and a low-valent rhodium complex capable of activating ketones and olefins simultaneously. Both cyclic and acyclic ketones can be mono-a-alkylated with simple terminal olefins, such as ethylene, propylene, 1-hexene, and styrene, selectively at the less hindered site; a large number of functional groups are tolerated.The pH/redox neutral and byproduct-free nature of this dual-activation approach shows promise for large-scale syntheses.
Identification and synthesis of new volatile molecules found in extracts obtained from distinct parts of cooked chicken
Delort, Estelle,Velluz, Alain,Frerot, Eric,Rubin, Mark,Jaquier, Alain,Linder, Simon,Eidman, Kirk F.,MacDougall, Brian S.
experimental part, p. 11752 - 11763 (2012/04/04)
Several chicken parts (skin, fat, juice) were cooked in different ways (roasting, simmering) and investigated separately for their volatile composition. In-depth GC/MS analysis of the separate fractions revealed several unknown molecules. Mass spectra interpretation allowed us to identify nine molecules for the first time in chicken, including cyclic aldehydes, cyclic ketones, and new δ-lactones containing an unsaturated linear chain. Identification was confirmed by chemical synthesis followed by comparison of the mass spectra and linear retention indices. The natural occurrence of five of these molecules is reported here for the first time in a natural product.
Intramolecular schmidt reaction involving primary azidoalcohols under nonacidic conditions: Synthesis of indolizidine (-)-167B
Kapat, Ajoy,Nyfeler, Erich,Giuffredi, Guy T.,Renaud, Philippe
supporting information; experimental part, p. 17746 - 17747 (2010/04/01)
(Chemical Equation Presented) A powerful intramolecular Schmidt reaction starting from primary azidoalcohols is reported. This approach involves a nonacidic activation of the alcohol via triflation. The synthetic potential offered by the mild reaction con
Amidino derivatives useful as nitric oxide synthase inhibitors
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, (2008/06/13)
The current invention discloses useful pharmaceutical compositions containing amidino derivative useful as nitric oxide synthase inhibitors.
Amidino dervatives useful as nitric oxide synthase inhibitors
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, (2008/06/13)
The current invention discloses useful pharmaceutical compositions containing azepine derivatives useful as nitric oxide synthase inhibitors.
Substituted 2-iminopiperidines as inhibitors of human nitric oxide synthase isoforms
Webber, R. Keith,Metz, Suzanne,Moore, William M.,Connor, Jane R.,Currie, Mark G.,Fok, Kam F.,Hagen, Timothy J.,Hansen Jr., Donald W.,Jerome, Gina M.,Manning, Pamela T.,Pitzele, Barnett S.,Toth, Mihaly V.,Trivedi, Mahima,Zupec, Mark E.,Siong Tjoeng
, p. 96 - 101 (2007/10/03)
A series of analogues of 2-iminopiperidine have been prepared and shown to be potent inhibitors of the human nitric oxide synthase (NOS) isoforms. Methyl substitutions on the 4-position (3) or 4- and 6-positions (8) afforded the most potent analogues. These compounds exhibited IC50 values of 0.1 and 0.08 μM, respectively, for hiNOS inhibition. Substitution with cyclohexylmethyl at the 6-position (13) afforded an inhibitor that showed the best selectivity for hiNOS versus heNOS (heNOS IC50/hiNOS IC50 = 64). Following oral administration, inhibitors were found to decrease serum nitrite/nitrate levels in an in vivo rat endotoxin assay. This series of 2- iminopiperidines were prepared via the described synthetic methodologies. The effect of ring substitutions on potency and selectivity for this class of cyclic amidines as NOS inhibitors is described.
α-(Phenylthio)cyclopropylation of carbonyl compounds: Preparation of α-cyclopropyl ketones
Pohmakotr, Manat,Thisayukta, Jirakorn
, p. 6759 - 6762 (2007/10/03)
α-Chloro-α-(phenylthio)cyclopropane and α-acetoxy-α-(phenylthio)cyclopropane were found to react with the silyl enol ethers of some ketones in the presence of Lewis acid in dichloromethane to provide α-(phenylthio)cyclopropyl ketones, which were subjected to reduction with Ra-Ni to give the corresponding α-cyclopropyl ketones.
Biosynthesis of the Hypotensive Metabolite Oudenone by Oudemansiella radicata. 1. Intact Incorporation of a Tetraketide Chain Elongation Intermediate
Tsantrizos, Youla S.,Zhou, Fei,Famili, Parsa,Yang, Xianshu
, p. 6922 - 6929 (2007/10/03)
The biosynthesis of the fungal metabolite oudenone (1) was investigated in cultures of Oudemansiella radicata.Feeding experiments using 13C- and 2H-labeled precursors, as well as NMR analyses of the labeled metabolite, suggested a polyketide origin.The incorporation of six acetate units into the carbon skeleton of 1 was observed when cultures were fed the N-acetylcysteamine thioester derivative of 13C-labeled acetate.Labeling of oudenone (1) from succinate or L-glutamic acid was not observed, whereas the pattern of 13C labeling from succinate was identical to that observed with acetate.The proposed advanced intermediate (5S)-5-hydroxyoctanoic acid (2) was synthesized as the deuterium labeled N-acetylcysteamine thioester derivative (S)-19 and successfully incorporated into 1.A biosynthetic scheme and cyclization mechanism, consistent with the experimental data, is proposed.
Alkylaluminum Halide Induced Cyclization of Unsaturated Carbonyl Compounds
Snider, Barry B.,Karras, Michael,Price, Robert T.,Rodini, David J.
, p. 4538 - 4545 (2007/10/02)
2,6-Dimethyl-5-heptenal (3) and 5-octenal (24) undergo concerted ene reactions with 1 equiv of Me2AlCl and cation-olefin cyclizations with 2 equiv of Me2AlCl, MeAlCl2, or EtAlCl2 to give a zwitterion which reacts to give several products including an ene
