76387-70-7Relevant articles and documents
Solid-phase synthesis and CD spectroscopic investigations of novel β-peptides from L-aspartic acid and β-amino-L-alanine
Ahmed, Sahar,Beleid, Reem,Sprules, Tara,Kaur, Kamaljit
, p. 25 - 28 (2007)
(Chemical Equation Presented) A solid-phase synthesis method for the preparation of novel β3 and β2-peptides derived from L-aspartic acid and β-amino-L-alanine, respectively, is described. The methodology allows independent buildup of the β-peptide backbone and the introduction of sequential side chain substitutions. Representative peptides from the two classes, an amino-substituted β3-hexapeptide and an acyl-substituted β2-hexapeptide, have been prepared, and their solution conformation is studied by circular dichroism (CD) spectroscopy.
The microenvironment and pKaperturbation of aminoacyl-tRNA guided the selection of cationic amino acids
Hazra, Bibhas,Prasad, Mahesh,Roy, Rajat,Tarafdar, Pradip K.
supporting information, p. 8049 - 8056 (2021/10/04)
The proteinogenic lysine (Lys) and arginine (Arg) have multiple methylene groups between α-carbon and the terminal charged centre. Why nature did not select ornithine (Orn), 2,4-diamino butyric acid (Dab) and 2,3-diamino propionic acid (Dpr) with fewer methylene groups in the side chain remains an important question! The propensity of aminoacyl-tRNA (aa-tRNA) model substrates towards self-degradationviaintramolecular lactamization was studied using UV spectroscopy and1H-NMR titration, which showed that Lys and Arg remain stable, and Orn and Dab cyclize to lactam. Hydrophobicity-assisted surface mediated model peptide formation highlighted that the microenvironment and pKaperturbation led to poor regioselectivity (α-aminevs.terminal amine) in Dpr and other non-proteinogenic analogues. The α-selectivity became even poorer in the presence of phosphate, making them ill-suited for peptide synthesis. Superior regioselectivity of the Lys aa-tRNA model substrate suggests that the extra methylene bridge helped nature to separate the microenvironments of the α-amine and ε-amine to synthesize the peptide backbone.
Syntheses of Enantiopure 1,2-Ethylenediamines with Tethered Secondary Amines of the Formula H 2NCH 2CH[(CH 2) nNHMe]NH 2(n = 1-4) from α-Amino Acids: New Agents for Asymmetric Catalysis
Kabes, Connor Q.,Gunn, Jack H.,Selbst, Maximilian A.,Lucas, Reagan F.,Gladysz, John A.
, p. 3277 - 3285 (2020/11/02)
Tris(hydrochloride) adducts of the title compounds-are prepared from the inexpensive α-amino acids H 2 N(C=O)CH 2 CH(NH 2)CO 2 H, HO(C=O)(CH 2) n ′ CH(NH 2)CO 2 H (n ′ = 1, 2), and H2 N(CH 2) 4 CH(NH 2)CO 2 H, respectively (steps/overall yield = 5/32, 7/30, 7/33, 5/38). The NH 2 group that is remote from the secondary amine is installed via BH 3 reduction of an amide [-(C=O)NR 2[ derived?-from an α-amino carboxylic acid. The MeNHCH 2 units are introduced by BH 3 reductions of alkyl carbamate [RO(C=O)NHCH 2-; R = Et, t-Bu] or amide [MeHN(C=O)-] moieties.
Total synthesis of (-)-aplaminal by Buchwald-Hartwig cross-coupling of an aminal
Ohyoshi, Takayuki,Akemoto, Kei,Taniguchi, Ayaka,Ishihara, Takuma,Kigoshi, Hideo
, p. 18442 - 18444 (2019/12/06)
The concise total synthesis of an unusual alkaloid, aplaminal, has been accomplished. The synthetic feature is the Buchwald-Hartwig cross-coupling between a novel triazabicyclo[3.2.1]octane core and an aromatic bromide. The practicality of our approach provides aplaminal analogs and preliminary structure-cytotoxicity relationships of an aromatic moiety were achieved.