83460-84-8Relevant academic research and scientific papers
Synthesis of chiral non-racemic intermediates and Arg-Gly-Asp mimetics by CaLB-catalyzed resolution
Cardillo, Giuliana,Gennari, Arianna,Gentilucci, Luca,Mosconi, Elisa,Tolomelli, Alessandra,Troisi, Stefano
experimental part, p. 96 - 102 (2010/04/06)
The reactivity of both the ester and amine functions present in β-amino esters was tested in order to obtain the synthesis of enantiopure αvβ3 and α5β1 integrin ligands. CaLB successfully catalyzed both the enantioselective transesterification and the N-acylation of racemic β-amino esters, allowing the isolation of intermediates for the preparation of Arg-Gly-Asp (RGD) mimetic compounds. In particular, a CaLB-catalyzed amidation reaction with unprotected p-aminobenzylamine reduced the number of synthetic steps, thus avoiding protection and deprotection of the intermediate compounds. Following this procedure, RGD mimetics were isolated with high yields and enantiomeric purities.
One-pot hydrogenation conditions for a sequential process to (+)-monomorine
Kim, Guncheol,Jung, Sung-do,Lee, Eun-ju,Kim, Nakjeong
, p. 5395 - 5398 (2007/10/03)
(+)-Monomorine has been synthesized under mild hydrogenation conditions initiating deprotection followed by intramolecular, sequential reductive amination reactions. The precursors could be prepared concisely using B-alkyl Suzuki cross coupling of a chiral homoallylamine and a vinyl iodide or an iodofuran derivative.
NOVEL BETA-LACTAM COMPOUNDS AND PROECSS FOR PRODUCING THE SAME
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, (2008/06/13)
1. A β-lactam compound of the formula [1]; ???wherein R1 is a lower alkyl, a lower alkyl substituted by a hydroxy; R2 is a hydrogen, a lower alkyl; X is O, S, NH; m and n are 0 to 4, Y1 is a halogen, cyano, a hydroxy, an amino, a lower alkyloxy, a lower alkylamino, a carboxy, a carbamoyl, a lower alkyl, etc., Y2 is hydrogen, an alkyl, cyano, -C(R3)=NR4 (wherein R3 and R4 are hydrogen, an amino, an alkyl, etc., or R3 and R4 may combine each other together with the nitrogen atom to form a 5- to 7-membered heterocyclic group), or a pharmaceutically acceptable salt thereof, or a non-toxic ester thereof, which has an excellent antibacterial activity against Gram-positive bacteria, especially against MRSA and MRCNS.
Synthesis of N-Methyl-N-{(1S)-1-[(3R)-pyrrolidin-3-yl]ethyl} amine
Fleck, Thomas J.,McWhorter Jr., William W.,DeKam, Richard N.,Pearlman, Bruce A.
, p. 9612 - 9617 (2007/10/03)
N-Methyl-N-{(1S)-1-[(3R)-pyrrolidin-3-yl]ethyl} amine (1)1 is a key intermediate in the preparation of premafloxacin (2), which was under development as an antibiotic for use against pathogens of veterinary importance. This paper describes the development of a practical, efficient, and stereoselective process for the preparation of 1 from isobutyl (3S)-3-{methyl[(1S)-1-phenylethyl]-amino}butanoate (5c). The key steps in the synthetic sequence are an asymmetric Michael addition, which yields 5c, and a stereoselective alkylation, which yields (3S,4S)-3-allyl-1,4-dimethylazetidin-2-one (17).
On the enantioselective hydrogenation of isomeric β-acylamido β-alkylacrylates with chiral Rh(I) complexes - Comparison of phosphine ligands and substrates
Heller, Detlef,Holz, Jens,Komarov, Igor,Drexler, Hans-Joachim,You, Jingsong,Drauz, Karheinz,Boerner, Armin
, p. 2735 - 2741 (2007/10/03)
The rhodium(I)-catalyzed enantioselective hydrogenation of E- and Z-configured β-acylamido β-alkylacrylates as well as of isomeric mixtures has been investigated. As ligands 1,2-bisphospholanes like DuPHOS, BPE and Me4-BASPHOS have been tested,
1. Use of the Wolff Rearrangement of Diazo Ketones from Amino Acids as a Synthetic Method for the Formation of Oligonucleo-peptides: A Novel Approach to Chimeric Biomolecules
Guibourdenche, Christel,Seebach, Dieter,Natt, Francois
, p. 1 - 13 (2007/10/03)
Photolysis and Ag-benzoate-catalyzed decomposition of the diazo ketones 2 and 4 derived from Z-Ala-OH and Z-Ala-Ala-OH in the presence of oligonucleotide derivatives bearing at the 5′-terminus an NH2 instead of the OH group, or an aminohexyl phosphate group lead to Z-protected 3-aminobutanoyl and to Z-Ala-β-HAla derivatives, respectively (conjugates 12, 13, and 17-23, Schemes 3-5). In solution, this amide-forming acylation reaction could be realized only with oligomers containing up to 8 unprotected nucleotide building blocks (Schemes 3 and 4). With the analogous polymer-bound and protected oligonucleotide derivatives as amino nucleophiles, excellent yields were obtained with all chain lengths tested (up to 15mer, Scheme 5). The products were purified by reversed-phase HPLC and characterized by MALDI-TOF mass spectrometry (Figs. 2-4, Table 2) and by capillary gel electrophoresis (Fig. 2).
On the Preparation of β-Amino Acids from α-Amino Acids Using the Arndt-Eistert Reaction: Scope, Limitations and Stereoselectivity. Application to Carbohydrate Peptidation. Stereoselective α-Alkylations of Some β-Amino Acids
Podlech, Joachim,Seebach, Dieter
, p. 1217 - 1228 (2007/10/02)
The Arndt-Eistert homologation of α-amino acids was studied to determine the stereoselectivity in this reaction by chromatographic up-to-date analytical methods.While carbamate-protected phenylglycine was transformed to the corresponding β-amino acid methyl ester with a stereoselectivity of only 9:1, all other tested amino acid derivatives (Ala, Phe, Ser, Orn, tert-Leu and perhydro-azepine-2-carboxylic acid, suitably protected) were homologated with full retention of configuration (products 9-17).The intermediate diazo ketones 1-8 were purified and characterized by their NMR spectra.When nucleophiles derived from partially protected sugars were present during decomposition of the diazo ketones (derived from amino acids or dipeptides), a strong dependence of the yield (products 21-24) on the degree of steric hindrance of the nucleophilic OH group was observed.Two of the β-amino acids obtained from the homologation reaction were transformed to α-substituted (25-27, 31, 32) and α,α-disubstituted β-amino acid derivatives (28, 29) with excellent selctivities (in most cases, a single diastereoisomer was obtained). - Key Words: β-Amino acids, α-branched/Glycopeptides
Die Arndt-Eistert-Reaktion in der Peptidchemie: ein einfacher Zugang zu Homopeptiden
Podlech, Joachim,Seebach, Dieter
, p. 507 - 509 (2007/10/02)
Stichworte: Arndt-Eistert-Reaktionen. β-Aminosaeuren.Dihydrooxazinone.Homopeptide.Peptid-Analoga
Synthesis of β-Amino-acid Peptides. Part 3. Preparation of Racemic and Chiral 3-Aminobutyric Acid Derivatives and Peptides Using Dihydrooxazin-6-ones and Conventional Coupling Reagents
Drey, Charles N. C.,Mtetwa, Eli
, p. 1587 - 1592 (2007/10/02)
Peptides of R,S and S-3-aminobutyric acid have been prepared by conventional methods and also by using chiral oxazin-6-ones, the latter method proving to be superior because of the absence of the side-reactions.S-3-Aminobutyric acid derivatives were prepared by Arndt-Eistert homologation.
