188348-02-9Relevant academic research and scientific papers
Polysilane-Immobilized Rh-Pt Bimetallic Nanoparticles as Powerful Arene Hydrogenation Catalysts: Synthesis, Reactions under Batch and Flow Conditions and Reaction Mechanism
Miyamura, Hiroyuki,Suzuki, Aya,Yasukawa, Tomohiro,Kobayashi, Shu
, p. 11325 - 11334 (2018/09/06)
Hydrogenation of arenes is an important reaction not only for hydrogen storage and transport but also for the synthesis of functional molecules such as pharmaceuticals and biologically active compounds. Here, we describe the development of heterogeneous Rh-Pt bimetallic nanoparticle catalysts for the hydrogenation of arenes with inexpensive polysilane as support. The catalysts could be used in both batch and continuous-flow systems with high performance under mild conditions and showed wide substrate generality. In the continuous-flow system, the product could be obtained by simply passing the substrate and 1 atm H2 through a column packed with the catalyst. Remarkably, much higher catalytic performance was observed in the flow system than in the batch system, and extremely strong durability under continuous-flow conditions was demonstrated (>50 days continuous run; turnover number >3.4 × 105). Furthermore, details of the reaction mechanisms and the origin of different kinetics in batch and flow were studied, and the obtained knowledge was applied to develop completely selective arene hydrogenation of compounds containing two aromatic rings toward the synthesis of an active pharmaceutical ingredient.
A multikilogram-scale synthesis of (R)-methyl 2-[(1r,4R)-4-(tert-butoxy- carbonylamino)cyclohexyl]-2-(2-nitrophenylsulfonamido)acetate - A doubly protected building block with three points of variation
Carr, Gregory,Butterworth, Sam,Walker, Phil,Reck, Folkert,Geng, Bolin,Pandarinathan, Lakshmipathi
experimental part, p. 875 - 880 (2012/05/19)
A robust and scalable synthesis of (R)-methyl 2-[(1r,4R)-4-(tert- butoxycarbonylamino)cyclohexyl]-2-(2-nitrophenylsulfon-amido)acetate is reported. This serves as a scaffold for the preparation of trans-substituted aminocyclohexanes. The key synthetic step is the reduction of d-4-hydroxyphenylglycine, or a protected equivalent, to achieve the required regiochemistry across the cyclohexyl ring. Georg Thieme Verlag Stuttgart · New York.
Design, synthesis, and structure-activity relationship study of conformationally constrained analogs of indole-3-carboxamides as novel CB1 cannabinoid receptor agonists
Kiyoi, Takao,York, Mark,Francis, Stuart,Edwards, Darren,Walker, Glenn,Houghton, Andrea K.,Cottney, Jean E.,Baker, James,Adam, Julia M.
scheme or table, p. 4918 - 4921 (2010/11/04)
Novel tricyclic indole-3-carboxamides were synthesized as structurally restricted analogs of bicyclic indoles, and found to be potent CB1 cannabinoid receptor agonists. The CB1 agonist activity depended on the absolute configuration of the chiral center of the tricyclic ring. The preferred enantiomer was more potent than the structurally unconstrained lead compound. Structure-activity relationships in the amide side chain of the indole C-3 position were also investigated.
Synthesis of novel potent hepatitis C virus NS3 protease inhibitors: Discovery of 4-hydroxy-cyclopent-2-ene-1,2-dicarboxylic acid as a N-acyl-l-hydroxyproline bioisostere
Thorstensson, Fredrik,Wangsell, Fredrik,Kvarnstroem, Ingemar,Vrang, Lotta,Hamelink, Elizabeth,Jansson, Katarina,Hallberg, Anders,Rosenquist, Asa,Samuelsson, Bertil
, p. 827 - 838 (2007/10/03)
Potent tetrapeptidic inhibitors of the HCV NS3 protease have been developed incorporating 4-hydroxy-cyclopent-2-ene-1,2-dicarboxylic acid as a new N-acyl-l-hydroxyproline mimic. The hydroxycyclopentene template was synthesized in eight steps from commercially available (syn)-tetrahydrophthalic anhydride. Three different amino acids were explored in the P1-position and in the P2-position the hydroxyl group of the cyclopentene template was substituted with 7-methoxy-2-phenyl-quinolin-4-ol. The P3/P4-positions were then optimized from a set of six amino acid derivatives. All inhibitors were evaluated in an in vitro assay using the full-length NS3 protease. Several potent inhibitors were identified, the most promising exhibiting a Ki value of 1.1 nM.
Chiral electrophilic 'glycinal' equivalents. New synthons for optically active α-amino acids and 4-substituted 2-oxazolidinones
Matsunaga, Hirofumi,Ishizuka, Tadao,Kunieda, Takehisa
, p. 1275 - 1294 (2007/10/03)
The thermal reaction of 3-[(1S)-2-alkoxy-1-apocamphanecarbonyl]-2-oxazolones (21a-c) with dialkyl azodicarboxylates (9) results in exclusive formation of [4 + 2] type cycloadducts (22 and 23) with moderate levels of diastereofacial selection (up to 72% d.e.). The diastereomers thus obtained were readily purified and subsequent treatment with acidic methanol followed by removal of the auxiliary with LiBH4/MeOH (1:2) gave optically pure 4-methoxy-5-hydrazino-2-oxazolidinones (26 and 27), which serve as α-aminoaldehyde templates useful for the synthesis of a wide variety of optically active α-amino acids as well as 4-alkyl and 4-aryl-2-oxazolidinones.
