- Evaluation of a carbohydrate-π interaction in a peptide model system
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A carbohydrate-π interaction contributes -0.8 kcal mol-1 to the stabilization of a β-hairpin peptide. The Royal Society of Chemistry.
- Kiehna, Sarah E.,Laughrey, Zachary R.,Waters, Marcey L.
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- Synthesis, Spectroscopy, and Photocytotoxicity of Glycosylated Amino Acid Porphyrin Derivatives as Promising Molecules for Cancer Phototherapy
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To obtain molecules that can target malignant cells, two series of new meso glucosylporphyrins bearing amino acid residues are synthesized in four steps. The first series contained n meso glycosyl moieties and (4 -n) alanyl groups on the ortho or para positions of the meso phenyl. In the second series, the carbohydrate moiety is separated from the aryl substituent by a serine unit. Starting from p- or o-nitrobenzaldehyde, p- or o-acetylbenzaldehyde or -tolualdehyde, and pyrrole, the glycosylnitrophenylporphyrins 3-6 and tritolylporphyrins 8a,b are synthesized under optimized conditions tailored from Lindsey's method. The nitro function is then reduced and N-Fmoc-L-alanine or acetylglycosylated N-Fmoc-serine are coupled on the amino function. A detailed 1H and 13C NMR study allows complete structural elucidation. The UV-visible fluorescence and MALDI mass spectra are presented. Compounds 19-22 produced 1O2, and photocytotoxicities against the K562 leukemia cell line are compared to hematoporphyrin. As a result of their sensitizing abilities, these resultant compounds are of considerable interest for photodynamic therapy.
- Sol,Blais,Carre,Granet,Guilloton,Spiro,Krausz
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- Folding-induced CO2-soluble peptides
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The first CO2- and water-soluble peptide is reported, in which folding facilitates its solubility in CO2. The Royal Society of Chemistry.
- Kiehna, Sarah E.,Laughrey, Zachary R.,Waters, Marcey L.
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- Studies toward the site specific incorporation of sugars into proteins: Synthesis of glycosylated aminoacyl-tRNAs
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A series of glycosylated serine derivatives was synthesized from peracetylated sugars and Fmoc-protected serine; these were chemically esterified with the tris-(tetrabutylammonium) salt of pdCpA. The fully protected and deprotected glycosylated aminoacyl pdCpAs were ligated enzymatically to an abbreviated tRNA (tRNA-COH) to provide the title compounds that are key intermediates in the elaboration of glycoproteins using readthrough of a nonsense codon.
- Fahmi, Nour Eddine,Golovine, Serguei,Wang, Bixun,Hecht, Sidney M.
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- Effects of Glycosylation and d -Amino Acid Substitution on the Antitumor and Antibacterial Activities of Bee Venom Peptide HYL
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Glycosylation is a promising strategy for modulating the physicochemical properties of peptides. However, the influence of glycosylation on the biological activities of peptides remains unknown. Here, we chose the bee venom peptide HYL as a model peptide and 12 different monosaccharides as model sugars to study the effects of glycosylation site, number, and monosaccharide structure on the biochemical properties, activities, and cellular selectivities of HYL derivatives. Some analogues of HYL showed improvement not only in cell selectivity and proteolytic stability but also in antitumor and antimicrobial activity. Moreover, we found that the helicity of glycopeptides can affect its antitumor activity and proteolytic stability, and the α-linked d-monosaccharides can effectively improve the antitumor activity of HYL. Therefore, it is possible to design peptides with improved properties by varying the number, structure, and position of monosaccharides. What's more, the glycopeptides HYL-31 and HYL-33 show a promising prospect for antitumor and antimicrobial drugs development, respectively. In addition, we found that the d-lysine substitution strategy can significantly improve the proteolytic stability of HYL. Our new approach provides a reference or guidance for the research of novel antitumor and antimicrobial peptide drugs.
- Wu, Ming-Hao,Ai, Su,Chen, Qing,Chen, Xiang-Yan,Li, Hong-Jin,Li, Yu-Lei,Zhao, Xia
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p. 2293 - 2302
(2020/11/26)
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- Glycosylation of α-amino acids by sugar acetate donors with InBr 3. Minimally competent Lewis acids
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A simplified method for the preparation of Fmoc-serine and Fmoc-threonine glycosides for use in O-linked glycopeptide synthesis is described. Lewis acids promote glycoside formation, but also promote undesired reactions of the glycoside products. Use of 'minimally competent' Lewis acids such as InBr 3 promotes the desired activation catalytically, and with greatly reduced side products from sugar peracetates.
- Lefever, Mark R.,Szab, Lajos Z.,Anglin, Bobbi,Ferracane, Michael,Hogan, Joanna,Cooney, Lauren,Polt, Robin
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scheme or table
p. 121 - 125
(2012/05/20)
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- Facile synthesis of glycosylated Fmoc amino acid building blocks assisted by microwave irradiation
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The synthesis of glycosylated Fmoc amino acids by reaction of mono- and disaccharide peracetates with Fmoc amino acids having free carboxyl groups was rapidly promoted by Lewis acids (SnCl4, BF3·Et 2O) under microwave irradiation. The products are useful building blocks for the synthesis of glycopeptides.
- Yao, Nianhuan,Fung, Gabriel,Malekan, Hamed,Ye, Long,Kurth, Mark J.,Lam, Kit S.
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experimental part
p. 2277 - 2281
(2010/11/19)
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- Solid phase synthesis of O-glycoopioid peptides related to dermorphin
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Glycosylation of Fmoc-hydroxyamino acids with β-D-glucose pentaacetate has been carried out in the presence of several Lewis acids and BF3.Et2O has been found to be the most suitable one. Thus, 2,3,4,6-tetra-O-acetyl-β-D-glycopyranosyl derivatives of Fmoc-Ser/Thr/Tyr are prepared in a single step in reasonably good yields and high purity. The O-glycosylated derivatives are then converted to their corresponding trichlorophenyl esters for use in the solid phase synthesis of five glycoopioid peptides related to dermorphin. The effect of glycosylation on biological activity of dermorphin has been studied. Among the peptides synthesized, [Tyr(β-D-Glc)5]dermorphin and [Ser(β-D-Glc)5, Tyr7)]dermorphin exhibit considerable analgesic activity of about 80-90% compared to morphine and antidiarrhoeal activity of about 50% compared to dermorphin.
- Sivanandaiah,Suresh Babu,Shankaramma
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p. 760 - 767
(2007/10/03)
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- Synthesis of a chromogenic proline-containing glycopeptide
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A convenient synthesis of a chromogenic glycopeptide, O-(β-D-glucopyranosyl)-Ser-Pro-4-nitroanilide, involving the direct glycosylation of Fmoc-Ser-OH, coupling of L-proline-4-nitroanilide and sequential deprotection without diketopiperazine formation is reported.
- Steffan, Wolfram,Schutkowski, Mike,Fischer, Gunter
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p. 313 - 314
(2007/10/03)
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- Preparation of Building Blocks for Glycopeptide Synthesis by Glycosylation of Fmoc Amino Acids Having Unprotected Carboxyl Groups
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Nα-Fmoc amino acids with an unprotected α-carboxyl group have been glycosylated with carbohydrate 1,2-trans peracetates using Lewis acids as promoters.Aliphatic and phenolic O- and S-glycosides of amino acids, with a 1,2-trans anomeric configuration, were obtained as products in 34-65percent yields.The glycosylated building blocks have the protective groups of choice (i.e.O-acetyl and Nα-Fmoc) for direct use in stepwise synthesis of glycopeptides.The starting materials are readily available and the method does not require an extensive experience in synthetic carbohydrate chemistry.
- Salvador, Lourdes A.,Eloffson, Mikael,Kihlberg, Jan
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p. 5643 - 5656
(2007/10/02)
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- Improved method for the synthesis of o-glycosylated fmoc amino acids to be used in solid-phase glycopeptide synthesis (Fmoc = fluoren-9-ylmethoxycarbonyl)
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The building blocks O1-(2,3,4,6-tetra-O-acetyl-β-D- galactopyranosyl)-Nα(fluoren-9-ylmethoxycarbonyl)serine (5)and O 1-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl) -Nα-(fluoren-9-ylmethoxycarbonyl)threonine (6) for use in solid-phase glycopeptide synthesis can be obtained via their ally esters by mild treatment with tetrakis(triphenylphosphine)palladium(0) and tributyltin hydride with no Fmoc elimination or sugar cleavage or anomerization.
- De La Torre, Beatriz G.,Torres, Josep L.,Bardaji, Eduard,Clapes, Pere,Xaus, Nuria,Jorba, Xavier,Calvet, Silvia,Albericio, Fernando,Valencia, Gregorio
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p. 965 - 967
(2007/10/02)
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