H-Lys(Fmoc)-OH

H-Lys(Fmoc)-OH

The production of anti-hexapeptide antibodies which recognize the S7, L6 and L13 ribosomal proteins of Escherichia coli.[Pubmed:11931584]

J Pept Sci. 2002 Mar;8(3):118-24.

Here we report the synthesis of the N-terminal hexapeptide H-Pro-Arg-Arg-Arg-Val-Ile-OH of the E. coli ribosomal protein S7. the C-terminal hexapeptide H-Lys-Glu-Ala-Lys-Lys-Lys-OH of L6 and the C-terminal hexapeptide H-Pro-Gln-Val-Leu-Asp-Ile-OH of L13. All peptides were prepared by SPPS following the Fmoc-strategy, using DIC/HOBt and/or HBTU as coupling reagents and 2-chlorotrityl chloride resin as the solid support. The carrier linked synthetic peptides were injected into rabbits and elicited an anti-peptide response. These anti-hexapeptide antibodies were found to recognize the corresponding peptides and proteins.

Synthesis of glycosylated tuftsins and tuftsin-containing IgG fragment undecapeptide.[Pubmed:2019473]

Int J Pept Protein Res. 1991 Feb;37(2):112-21.

Syntheses are described of two new tuftsin derivatives containing a 2-acetamido-2-deoxy-D-galactopyranosyl unit alpha- or beta-glycosidically linked to the threonine's hydroxy side chain function and of the glycosylated undecapeptide corresponding to the tuftsin region of the heavy chain of IgG (amino acid sequence 289-299). The glycosylated tuftsins were synthesized by the solution procedure. Fmoc-[Gal NAc(Ac)3 alpha]Thr-OH and Fmoc-[GalNAc(Ac)3 beta]Thr-OH were allowed to react with H-Lys(Z)-Pro-Arg(NO2)-OBzl by the mixed anhydride procedure and the resulting glycosylated tetrapeptides were fully deblocked by catalytic hydrogenation followed by treatment with potassium cyanide, purified by ion exchange chromatography and characterized by analytical HPLC, elemental and amino acid analyses, optical rotation, and proton NMR spectroscopy. Synthesis of the glycosylated undecapeptide was achieved by the continuous flow solid phase procedure on 4-hydroxymethylphenoxyacetyl-norleucyl derivatized Kieselguhr-supported resin. Fmoc-amino acid symmetrical anhydrides or pentafluorophenyl esters, in the presence of N-hydroxybenzotriazole, were used as the acylating agents. To mimic the native sequence of the tuftsin region at the Fc-domain of immunoglobulin G a 2-acetamido-2-deoxy-beta-D-glucopyranosyl unit was N-glycosidically linked to the amide side chain of Asn 297. The glycosylated asparagine residue was introduced as N2-fluorenylmethyloxycarbonyl-N4-(2-acetamido-3,4,6-tri-O-acetyl-2 -deoxy-beta-D - glucopyranosyl)-asparagine pentafluorophenyl ester. After cleavage from the resin the glycopeptide was deprotected, purified by ion exchange chromatography, and characterized by analytical HPLC, amino acid analysis, high voltage electrophoresis, and proton NMR. The conformational features of the glyco-undecapeptide were determined by circular dichroism measurements both in water and in 98% trifluoroethanol. Results of biological assays will be published elsewhere.

Synthesis of O-glycosylated tuftsins by utilizing threonine derivatives containing an unprotected monosaccharide moiety.[Pubmed:2119354]

Int J Pept Protein Res. 1990 Jul;36(1):86-96.

Synthesis is described of four tuftsin derivatives containing a D-glucopyranosyl or a D-galactopyranosyl unit covalently linked to the hydroxy side chain function of the threonine residue through either an alpha or beta O-glycosidic linkage. Fmoc-threonine derivatives containing the suitable unprotected sugar were used for incorporating the O-glycosylated amino acid residue. Z-Thr[alpha-Glc(OBzl)4]-OBzl and Z-Thr[alpha-Gal(OBzl)4]-OBzl were prepared from the tetra-O-benzylated sugar and Z-Thr-OBzl by the trichloroacetimidate method in the presence of trimethylsilyl trifluoromethane sulfonate. The alpha glycosylated threonine derivatives were converted into Fmoc-Thr(alpha-Glc)-OH and Fmoc-Thr(alpha-Gal)-OH by catalytic hydrogenation followed by acylation with Fmoc-OSu. beta-Glucosylation and beta-galactosylation of threonine were carried out by reacting the proper per-O-acetylated sugar with Z-Thr-OBzl and boron trifluoride ethyl etherate in dichloromethane. Catalytic hydrogenation of the beta-O-glycosylated threonine derivatives followed by acylation with Fmoc-OSu and deacetylation with methanolic hydrazine yielded Fmoc-Thr(beta-Glc)-OH and Fmoc-Thr(beta-Gal)-OH, respectively. The O-glycosylated threonine derivatives were then reacted with H-Lys(Z)-Pro-Arg(NO2)-OBzl in the presence of DCC and HOBt and the resulting glycosylated tuftsin derivatives were fully deblocked by catalytic hydrogenation, purified by HPLC, and characterized by optical rotation, amino acid analysis, and 1H NMR. The beta-galactosylated tuftsin was also prepared by the continuous flow solid phase procedure.