146453-32-9Relevant articles and documents
Consequences of isostructural main-chain modifications for the design of antimicrobial foldamers: Helical mimics of host-defense peptides based on a heterogeneous amide/urea backbone
Claudon, Paul,Violette, Aude,Lamour, Karen,Decossas, Marion,Fournel, Sylvie,Heurtault, Beatrice,Godet, Julien,Mely, Yves,Jamart-Gregoire, Brigitte,Averlant-Petit, Marie-Christine,Briand, Jean-Paul,Duportail, Guy,Monteil, Henri,Guichard, Gilles
, p. 333 - 336 (2010)
"Chemical Equation Presented" Fraternal twins: Oligoureas and Y-peptides are isosteric, quasi-isostructural helical foldamers endowed with distinct blomolecular recognition properties. Combination of the two backbones to generate urea/amide hybrids (see picture) was found to give more potent yet less cytotoxic antimicrobial helical foldamers.
Asymmetric total synthesis of the caspase-1 inhibitor (-)-berkeleyamide A
Kulkarni, Swapnil J.,Pedduri, Yakambram,Chittiboyina, Amar G.,Avery, Mitchell A.
experimental part, p. 3113 - 3116 (2010/07/15)
The asymmetric total synthesis of (-)-berkeleyamide A (1), a naturally occurring caspase-1 inhibitor, has been achieved by employing Evans' syn-aldol reaction of N-acyl-(4R)-benzyl oxazolidin-2-one 3 as the key step.
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.