85677-12-9Relevant articles and documents
HETEROCYCLIDENE-N-(ARYL)ACETAMIDE DERIVATIVE
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Page/Page column 110, (2009/12/23)
The blow-described formula (I): [Ch. 1] a compound represented by formula (I) : (wherein k, m, n, and p each represent 0 to 2; j and q represents 0 or 1; R1 represents a halogen atom, a hydrocarbon group, a heterocyclic group, an alkoxy group,
Asymmetric synthesis of the Roche ester and its derivatives by rhodium-INDOLPHOS-catalyzed hydrogenation
Wassenaar, Jeroen,Kuil, Mark,Reek, Joost N. H.
supporting information; scheme or table, p. 1610 - 1614 (2009/07/18)
(S)-3-Hydroxy-2-methylpropionate, known as the Roche ester, and several of its derivatives were successfully synthesized through asymmetric rhodium-catalyzed hydrogenation, using INDOLPHOS (diisopropyl{1-[(S)-3,5-dioxa- 4-phosphacyclohepta[ 2,1-a;3,4-a′]dinaphthalen-4-yl]-3-methyl-2-indolyl} phosphine) as the chiral ligand, in excellent yield and the highest ee reported up to now (TOF over 5500 h-1 at 25°C; up to 98% ee at -40°C).
Cleavage of β-lactone ring by serine protease. Mechanistic implications
Kim, Dong H.,Park, Jeong-il,Chung, Sang J.,Park, Jung Dae,Park, No-Kyung,Han, Jong Hoon
, p. 2553 - 2560 (2007/10/03)
Both enantiomers of 3-benzyl-2-oxetanone (1) were found to be slowly hydrolyzed substrates of α-chymotrypsin having kcat values of 0.134±0.008 and 0.105±0.004 min-1 for (R)-1 and (S)-1, respectively, revealing that α-CT is virtually unable to differentiate the enantiomers in the hydrolysis of 1. The initial step to form the acyl-enzyme intermediate by the attack of Ser-195 hydroxyl on the β-lactone ring at the 2-position in the hydrolysis reaction may not be enzymatically driven, but the relief of high ring strain energy of β-lactone may constitute a major driving force. The deacylation step is also attenuated, which is possibly due to the hydrogen bond that would be formed between the imidazole nitrogen of His-57 and the hydroxyl group generated during the acylation in the case of (R)-1, but in the α-CT catalyzed hydrolysis of (S)-1 the imidazole nitrogen may form a hydrogen bond with the ester carbonyl oxygen.
Design and synthesis of a conformationally restricted trans peptide isostere based on the bioactive conformations of saquinavir and nelfinavir
Edmonds,Abell
, p. 3747 - 3752 (2007/10/03)
The design and synthesis of a new peptide isostere which contains a trans alkene core is described. The key step involves a Wadsworth-Emmons reaction between chiral aldehyde (2S)-9a and chiral phosphonate 7 under base-sensitive conditions to give a chiral enone (2R)-24a which was reduced to afford the desired trans alkene isosteres (2R,5R)-6a and (2R,5S)-6b (Scheme 6). A potential application of this isostere in the synthesis of HIV protease inhibitors is also discussed.
Process for producing propionic acid derivatives
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, (2008/06/13)
A process for producing a 2-aralkyl-3-hydroxypropionic acid (or its ester), comprising the steps of: reacting a 3-hydroxy-2-methylene-3-arylpropionic acid ester, easily obtained by the reaction of an arylaldehyde with an acrylic acid ester, with an acid anhydride to form a 2-aralkylidene-3-acyloxypropionic acid ester; subjecting the same to hydrolysis or alcoholysis; and reducing the resulting 2-aralkylidene-3-hydroxypropionic acid or its ester. The reduction step may be conducted in the presence of a base.
Highly regioselective intramolecular hydroxymethylation of α,β-unsaturated carboxylic acids
Linker, Torsten,Maurer, Michael,Rebien, Frank
, p. 8363 - 8366 (2007/10/03)
A convenient synthesis of hydroxy esters 7 and lactones 8 by starting from easily available α,β-unsaturated carbocylic acids 4 is described. The key step of this transformation is a hitherto unknown radical cyclization of silyl esters, which exhibits a high degree of regioselectivity through steric and orbital control.
Xanthines with C8 chiral substituents as potent and selective adenosine A1 antagonists.
Peet,Lentz,Dudley,Ogden,McCarty,Racke
, p. 4015 - 4020 (2007/10/02)
Several 8-substituted 1,3-dipropylxanthines were synthesized, and their receptor binding affinities at adenosine A1 and A2 receptors were measured. When enantiomeric pairs of compounds were examined, the R enantiomers were significantly more potent than the corresponding S enantiomers. The most potent compound at the A1 receptor was (R)-3,7-dihydro-8-(1-methyl-2-phenylethyl)-1,3-dipropyl-1H-purine-2,6-di one (5a; MDL 102,503), whose Ki value at the A1 receptor was 6.9 nM. However, a more selective compound was (R)-3,7-dihydro-8-(1-phenylpropyl)-1,3-dipropyl-1H-purine-2,6-dione (5d; MDL 102,234), which had a Ki value of 23.2 nM at the A1 receptor and an A2/A1 ratio of 153.
HYDROFORMYLATION OF OLEFINS WITH PARAFORMALDEHYDE CATALYZED BY RHODIUM COMPLEXES
Okano, Tamon,Kobayashi, Teruyuki,Konishi, Hisatoshi,Kiji, Jitsuo
, p. 4967 - 4968 (2007/10/02)
The addition of formaldehyde to olefins is efficiently catalyzed by RhH2(O2COH)2 and gives the corresponding aldehydes in neutral solution.
