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.
A New Type of Safety-catch Linker cleaved by Intramolecular Activation of an Amide Anchorage and allowing Aqueous Processing in Solid-phase Peptide Synthesis
Sola, Regine,Saguer, Philippe,David, Marie-Laure,Pascal, Robert
, p. 1786 - 1788 (1993)
The N3-phenyloxycarbonyl-L-2,3-diaminopropionic acid residue behaves as a versatile linker displaying high stability under neutral and acidic conditions but undergoes activation under mild alkaline conditions for the release of peptide acids or amides by nucleophilic cleavage.
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.
THERAPEUTIC COMPOUNDS AND METHODS
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Page/Page column 33, (2020/01/31)
Disclosed herein are compounds of formula I: (I) or pharmaceutically acceptable salts thereof, wherein R1, R2, and R3 may any of the values defined herein, as well as compositions comprising such compounds. Also disclosed are methods for treating diseases including neurodegenerative disorders such as Parkinson's Disease and Alzheimer's Disease.
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.
2,3-Diaminopropanols obtained from D-serine as intermediates in the synthesis of protected 2,3-L-diaminopropanoic acid (L-DAP) methyl esters
Aiello, Donatella,Athanassopoulos, Constantinos M.,Mazzotti, Fabio,Siciliano, Carlo,Temperini, Andrea,de Luca, Pierantonio
, (2020/03/23)
A synthetic strategy for the preparation of two orthogonally protected methyl esters of the non-proteinogenic amino acid 2,3-l-diaminopropanoic acid (l-Dap) was developed. In these structures, the base-labile protecting group 9-fluorenylmethyloxycarbonyl (Fmoc) was paired to the p-toluensulfonyl (tosyl, Ts) or acid-labile tert-butyloxycarbonyl (Boc) moieties. The synthetic approach to protected l-Dap methyl esters uses appropriately masked 2,3-diaminopropanols, which are obtained via reductive amination of an aldehyde prepared from the commercial amino acid Nα-Fmoc-O-tert-butyl-d-serine, used as the starting material. Reductive amination is carried out with primary amines and sulfonamides, and the process is assisted by the Lewis acid Ti(OiPr)4. The required carboxyl group is installed by oxidizing the alcoholic function of 2,3-diaminopropanols bearing the tosyl or benzyl protecting group on the 3-NH2 site. The procedure can easily be applied using the crude product obtained after each step, minimizing the need for chromatographic purifications. Chirality of the carbon atom of the starting d-serine template is preserved throughout all synthetic steps.
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.
High-efficiency preparation method of D-dencichine
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, (2019/01/21)
The invention relates to a high-efficiency synthesis method of a hemostasis compound D-dencichine, comprising the following steps: firstly enabling D-serine to react with di-tert-butyl dicarbonate ester to generate Boc-D-serine, then generating Gabriel reaction with hydroxy of methylsulfonyl chloride activated Boc-D--serine to obtain N-alpha-Boc-D-alpha, beta-diaminopro, finally condensing with oxalate mono-methyl ester sylvite then performing hydrolytic acidification to obtain a dencichine crude product, and purifying to obtain a dencichine competitive product, with the product content reaching more than 99.8%. Compared with existing D-dencichine synthesis methods, the reaction condition is more mild, the operation is simple and convenient, the material cost is relatively low, and the hemostasis compound D-dencichine is environment-friendly, is suitable for industrial production, and solves the problem of resource for later development of clinical trial of D-dencichine.
Optimized syntheses of Fmoc azido amino acids for the preparation of azidopeptides
Pícha, Jan,Budě?ínsky, Milo?,Machá?ková, Kate?ina,Collinsová, Michaela,Jirá?ek, Ji?í
, p. 202 - 214 (2017/04/06)
The rise of CuI-catalyzed click chemistry has initiated an increased demand for azido and alkyne derivatives of amino acid as precursors for the synthesis of clicked peptides. However, the use of azido and alkyne amino acids in peptide chemistry is complicated by their high cost. For this reason, we investigated the possibility of the in-house preparation of a set of five Fmoc azido amino acids: β-azido l-alanine and d-alanine, γ-azido l-homoalanine, δ-azido l-ornithine and ω-azido l-lysine. We investigated several reaction pathways described in the literature, suggested several improvements and proposed several alternative routes for the synthesis of these compounds in high purity. Here, we demonstrate that multigram quantities of these Fmoc azido amino acids can be prepared within a week or two and at user-friendly costs. We also incorporated these azido amino acids into several model tripeptides, and we observed the formation of a new elimination product of the azido moiety upon conditions of prolonged couplings with 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate/DIPEA. We hope that our detailed synthetic protocols will inspire some peptide chemists to prepare these Fmoc azido acids in their laboratories and will assist them in avoiding the too extensive costs of azidopeptide syntheses. Experimental procedures and/or analytical data for compounds 3–5, 20, 25, 26, 30 and 43–47 are provided in the supporting information.
Fluorescently Labeled Amino Acids as Building Blocks for Bioactive Molecules
H?u?ler, Daniela,Gütschow, Michael
, p. 245 - 255 (2016/01/15)
A series of twelve fluorescently labeled amino acids were designed by assembling different coumarin, fluorescein, or nitrobenzo-furazan fluorophores with N-protected lysine or 2-aminopropionic acid. The synthesized amino acids were evaluated with regard to their spectroscopic properties. The easy introduction of the amino acids into peptides and peptidomimetics was exemplarily shown for one coumarin-labeled- amino acid.