151133-03-8Relevant articles and documents
Chemoselective Boron-Catalyzed Nucleophilic Activation of Carboxylic Acids for Mannich-Type Reactions
Morita, Yuya,Yamamoto, Tomohiro,Nagai, Hideoki,Shimizu, Yohei,Kanai, Motomu
, p. 7075 - 7078 (2015/06/25)
The carboxyl group (COOH) is an omnipresent functional group in organic molecules, and its direct catalytic activation represents an attractive synthetic method. Herein, we describe the first example of a direct catalytic nucleophilic activation of carbox
BETA-AMINO ACIDS AND METHODS AND INTERMEDIATES FOR MAKING SAME
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Page/Page column 17, (2011/10/02)
Disclosed are β-amino acids that are unsubstituted in the β position; that are substituted in the β position with an aryl group; that are substituted in the α position with an aryl group; that bear two substituents in the α position; and/or that are substituted in the α and β positions with groups which, together with the carbon atoms at the α and β positions, form a ring. Also disclosed are methods for making the above-mentioned β-amino acids and other β-amino acids which involve providing an α,β-unsaturated imide; converting the α,β-unsaturated imide to a 2-substituted-isoxazolidin-5-one; and converting the 2-substituted-isoxazolidin-5-one to a β-amino acid.
A designer axially chiral amino sulfonamide as an efficient organocatalyst for direct asymmetric mannich reactions of N-boc-protected imines
Kano, Taichi,Yamaguchi, Yukako,Maruoka, Keiji
supporting information; experimental part, p. 1838 - 1840 (2009/08/14)
The moderate nucleophilicity of the axially chiral amino sulfonamide (S)-1 suppresses the problematic side reactions, including aldol reactions, in the asymmetric Mannich reaction of N-Boc-protected imines with aldehydes. The corresponding adducts are obtained in good yield and excellent stereoselectivity (see scheme; Boc=tert-butoxycarbonyl, Tf=trifluoromethanesulfonyl).
A designer axially chiral amino sulfonamide as an efficient organocatalyst for direct asymmetric anti/-selective mannich reactions and syw-selective cross-aldol reactions
Kano, Taichi,Yamaguchi, Yukako,Maruoka, Keiji
supporting information; experimental part, p. 6678 - 6687 (2010/02/28)
A direct asymmetric Mannich reaction using a novel axially chiral amino sulfonamide (S)-3 that is highly anti- and enantioselective has been developed. For instance, in the presence of a catalytic amount of (S)-3, the reactions between aldehydes and a-imino esters proceeded smoothly to give anti Mannich products with a significantly higher antilsyn ratio and enantioselectivity than previously possible. By utilizing N-Boc-protected aro-matic imines instead of a-imino esters, the synthetically useful Boc protecting group and various aromatic or heteroaromatic substituents were installed into the anti Mannich products and consequently the substrate scope of the anri'-selective Mannich reaction and the synthetic utility of the anti Mannich products have been expanded. The axially chiral amino sulfonamide (S)-3 has also been successfully applied to asymmetric direct cross-aldol reaction between two different aldehydes. The catalyst (S)-3 has the advantage of giving mainly syn products, whereas proline shows the opposite anti selectivity.
Heterocyclic antiviral compounds
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Page/Page column 36, (2010/11/28)
Chemokine receptor antagonists, in particular, 3,7-diazabicyclo[3.3.0]octane compounds according to formula (I) wherein R1-R3 R6c and X1 are as defined herein are antagonists of chemokine CCR5 receptors which ar
HETEROCYCLIC ANTIVIRAL COMPOUNDS
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Page/Page column 168-169, (2010/02/15)
Chemokine receptor antagonists, in particular, 3,7-diazabicyclo [3.3.0] octane compounds according to formula (I) are antagonists of chemokine CCR5 receptors which are useful for treating or preventing an human immunodeficiency virus (HIV) infection, or treating AIDS or ARC. The invention further provides methods for treating diseases that are allieviated with CCR5 antagonists. The invention includes pharmaceutical compositions and methods of using the compounds for the treatment of these diseases. The invention further includes processes for the preparation of compounds according to formula (I).
Enantioselective synthesis of α,β-disubstituted-β-amino acids
Sibi, Mukund P.,Prabagaran, Narayanasamy,Ghorpade, Sandeep G.,Jasperse, Craig P.
, p. 11796 - 11797 (2007/10/03)
Highly diastereoselective and enantioselective addition of N-benzylhydroxylamine to imides 17 and 20-30 produces α,β-trans-disubstituted N-benzylisoxazolidinones 19 and 31-41. These reactions proceed in 60-96% ee with 93-99% de's using 5 mol % of Mg(NTf2)2 and ligand 18. The product isoxazolidinones can be hydrogenolyzed directly to provide ∞,β-disubstituted-β-amino acids. Copyright
Catalytic enantioselective addition of propionate units to imines: An efficient synthesis of anti-α-methyl-β-amino acid derivatives
Kobayashi, Shu,Kobayashi, Jun,Ishiani, Haruro,Ueno, Masaharu
, p. 4185 - 4190 (2007/10/03)
Optically active anti-α-methyl-β-amino acid derivatives have been prepared based on catalytic enantioselective addition of propionate units to simple and inert imines using a chiral zirconium complex. High reactivity and selectivity with wide substrate sc
Asymmetric Synthesis of anti-α-Alkyl-β-amino Acids
Davies, Stephen G.,Walters, Iain A. S.
, p. 1129 - 1140 (2007/10/02)
An investigation into the asymmetric induction accompanying alkylations of enolates derived from the highly diastereoselective conjugate addition of lithium (R)-N-benzyl-N-α-methylbenzylamide (R)-1 to crotonate and cinnamate esters has been performed.The
Asymmetric Syntheses of β-Phenylalanine, α-Methyl-β-phenylalanines and Derivatives
Davies, Stephen G.,Garrido, Narciso M.,Ichihara, Osamu,Walters, Iain A. S.
, p. 1153 - 1155 (2007/10/02)
A strategy of highly stereoselective conjugate additions of lithium (R)-(α-methylbenzyl)benzylamide to tert-butyl cinnamate and its 2-methyl derivative combined with appropriate tandem or sequential electrophilic quenches allows the asymmetric syntheses of β-phenylalanyl (95percent enantiomeric excess) and homochiral (2R,3S)- and (2S,3S)-α-methyl-β-phenylalanine and the corresponding β-lactams (3R,4S)- and (3S,4S)-3-methyl-4-phenylazetidinones.
