207924-92-3Relevant academic research and scientific papers
Effect of the Substituent and Amino Group Position on the Lipase-Catalyzed Resolution of γ-Amino Esters: A Molecular Docking Study Shedding Light on Candida antarctica lipase B Enantioselectivity
Ortega-Rojas, Marina A.,Castillo, Edmundo,Razo-Hernández, Rodrigo Said,Pastor, Nina,Juaristi, Eusebio,Escalante, Jaime
supporting information, p. 4790 - 4802 (2021/09/20)
The kinetic resolution of N-tert-butoxycarbonyl γ-amino methyl esters bearing different stereocenters at alpha (γ2), beta (γ3), or gamma (γ4) positions was carried out by enantioselective hydrolysis with Candida antarctica lipase B (CaLB) in 2-methyl-2-butanol solvent. The results show that the process is significantly less enantioselective for the γ2-amino methyl ester (E=2.5), the γ3-amino methyl ester (E=7.6), and the γ4-amino methyl ester (E=8.3) when compared with the kinetic resolution of analogous N-protected β3-amino esters (E>80). Based on these results, molecular docking studies were carried out, through which particular regions in the CaLB catalytic cavity were analyzed. The steric exclusion region composed of Ile189 and Val190 residues, together with the amino bonding region that induces a hydrogen bond with the Asp134 residue, appear to be responsible for the high selectivity in the resolution of carboxylic acid derivatives with beta stereocenters. This interaction is well preserved for β-amino esters as substrates. By contrast, γ-amino esters exhibit greater conformational diversity, so the effectiveness of the interaction is reduced, which apparently is responsible for the loss of enantioselectivity in the resolution process.
Potent Antimicrobial Activity of Lipidated Short α,γ-Hybrid Peptides
Benke, Sushil N.,Thulasiram, Hirekodathakallu V.,Gopi, Hosahudya N.
supporting information, p. 1610 - 1615 (2017/10/16)
Herein we report the potent antimicrobial activity of α,γ-hybrid lipopeptides composed of 1:1 alternating α- and γ-amino acids. Along with their potent antimicrobial activity against various Gram-positive and Gram-negative bacteria, these hybrid lipopepti
Conjugate Addition of Nitroalkanes to an Acrylate Equivalent. Stereocontrol at C-α of the Nitro Group through Double Catalytic Activation
Garcia, Jesus M.,Maestro, Miguel A.,Oiarbide, Mikel,Odriozola, Jose M.,Razkin, Jesus,Palomo, Claudio
supporting information; experimental part, p. 3826 - 3829 (2009/12/06)
Figur Presented An unprecedented highly selective direct conjugate addition of prochiral nitroalkanes (R ≠ H) to acrylate equivalents is described. The method employs a unique Lewis acid/Bronsted base/MS ternary catalytic system and affords products with
Trifluoroacetic acid-mediated intramolecular formal N-H insertion reactions with amino-α-diazoketones: A facile and efficient synthesis of optically pure pyrrolidinones and piperidinones
Yang, Hua,Jurkauskas, Valdas,Mackintosh, Nicole,Mogren, Tobias,Stephenson, Corey R. J.,Foster, Katherine,Brown, William,Roberts, Edward
, p. 800 - 808 (2007/10/03)
Trifluoroacetic acid (TFA) was found to promote intramolecular formal N-H insertion reactions. Upon treatment with TFA, optically pure N-Boc-β′-amino-α-diazoketones (5a-c) and N-Boc-γ′-amino-α-diazoketones (10a-d) can be converted, with retention of chira
γ-Peptides Forming More Stable Secondary Structures than α-Peptides: Synthesis and Helical NMR-Solution Structure of the γ-Hexapeptide Analog of H-(Val-Ala-Leu)2-OH
Hintermann, Tobias,Gademann, Karl,Jaun, Bernhard,Seebach, Dieter
, p. 983 - 1002 (2007/10/03)
For a comparison with the corresponding α- and β-hexapeptides H-(Val-Ala-Leu)2-OH (A) and H-(β-HVal-β-HAla-β-HLeu)2-OH (B), we have now prepared the corresponding γ-hexapeptide 1 built from the homochirally similar (S)-4-aminobutanoic acid, (R)-4-amino-5-methylhexanoic acid, and (R)-4-amino-6-methylheptanoic acid. The precursors were prepared either by double Arndt-Eistert homologation of the protected amino acids Boc-Val-OH, Boc-Ala-OH, and Boc-Leu-OH (Schemes 1 and 2), or by the superior route involving olefination/hydrogenation of the corresponding aldehydes (Boc-valinal, Boc-alaninal, and Boc-leucinal; Scheme 3). Conventional peptide-coupling methodology (EDC/HOBt) furnished the γ-hexapeptide 1 (through the intermediate γ-di- and γ-tripeptide derivatives 9-11). Analysis of NMR measurements in (D5)pyridine and CD3OH solution (COSY, TOCSY, HSQC, HMBC, ROESY) reveals that the γ-hexapeptide 1 adopts a right-handed helical structure ((P)-2.61 helix of ca. 5-A pitch, containing 14-membered H-bonded rings) which is to be compared with the left-handed helix of the corresponding β-peptide B ((M)-31 helix of 5-A pitch, 14-membered H-bonded rings) and with the familiar right-handed, so-called α-helix of α-peptides ((P)-3.61 helix of 5.4-A pitch, 13-membered rings). Like the helix sense, the helix dipole reverses when going from α- (N C) to β- (C N) to γ-peptides (N C). The surprising difference between the natural α-, and the analogous β- and γ-peptides is that the helix stability increases upon homologation of the residues.
