130832-25-6Relevant articles and documents
Synthesis of Characteristic Lipopeptides of the Human N-Ras Protein and their Evaluation as Possible Inhibitors of Protein Farnesyl Transferase
Stoeber, Paul,Schelhaas, Michael,Naegele, Edgar,Hagenbuch, Patrizia,Retey, Janos,Waldmann, Herbert
, p. 75 - 84 (1997)
Lipopeptides carrying a farnesyl thioether or a palmitic acid thioester and a farnesyl thioether were prepared from S-farnesyl cysteine methyl ester by N-terminal extension of the peptide chain employing the base labile Fmoc blocking group or the palladium(0) sensitive Aloc urethane.By means of this technique a lipohexapeptide representing the completely functionalized, i.e. palmitoylated and farnesylated C-terminus of the human N-Ras protein, was prepared.If acid labile blocking functions like the Boc group were used, upon deprotection an undesired addition of the acid to the double bonds of the farnesyl residue occured.Therefore, acid labile blocking groups should not be employed in the synthesis of farnesylated lipopeptides.The lipopeptide methyl esters which carry only a farnesyl group do not inhibit protein farnesyl transferase, whereas palmitoylated peptides are weak inhibitors of this enzyme.
Synthesis and anticancer activities of proline-containing cyclic peptides and their linear analogs and congeners
Ghosh, Keshab Ch,Duttagupta, Indranil,Bose, Chandra,Banerjee, Priyanjalee,Gayen, Anuran Kumar,Sinha, Surajit
, p. 221 - 236 (2019/01/19)
A solution phase method was adopted for the synthesis of proline-containing cyclic pentapeptide 2 and total synthesis of naturally occurring cyclic heptapeptide Reniochalistatin B 3. For the synthesis of 3, both divergent and convergent strategies were used to improve the overall yield from 12 to 25%. Different N and C terminal modified linear analogs and congeners of 2 and 3 were synthesized. Both cyclic peptides 2 and 3 and their linear analogs/congeners were evaluated for anti-cancer activity against HeLa cell line, among which pentapeptide 2 h and hexapeptide 3n with N-terminal protected hexafluoroisopropyl carbamates (HFIPC) interestingly showed higher cytotoxicity with an IC50 of 2.73 and 4.3 μM, respectively compared to their Boc-protected analogs 2a (IC50 20 μM) and 3c (IC50 38.51 μM) and cyclic peptides 2 (>100 μM) and 3 (47 μM). These results were further validated by biological experiments such as colony formation and wound healing assays.
Functional identification and structure determination of two novel prolidases from cog1228 in the amidohydrolase superfamily
Xiang, Dao Feng,Patskovsky, Yury,Xu, Chengfu,Fedorov, Alexander A.,Fedorov, Elena V.,Sisco, Abby A.,Sauder, J. Michael,Burley, Stephen K.,Almo, Steven C.,Raushel, Frank M.
experimental part, p. 6791 - 6803 (2011/05/05)
Two uncharacterized enzymes from the amidohydrolase superfamily belonging to cog1228 were cloned, expressed, and purified to homogeneity. The two proteins, Sgx9260c (gi|44242006) and Sgx9260b (gi|44479596), were derived from environmental DNA samples originating from the Sargasso Sea. The catalytic function and substrate profiles for Sgx9260c and Sgx9260b were determined using a comprehensive library of dipeptides and N-acyl derivative of l-amino acids. Sgx9260c catalyzes the hydrolysis of Gly-l-Pro, l-Ala-l-Pro, and N-acyl derivatives of l-Pro. The best substrate identified to date is N-acetyl-l-Pro with a value of kcat/Km of 3 × 105 M -1 s-1. Sgx9260b catalyzes the hydrolysis of l-hydrophobic l-Pro dipeptides and N-acyl derivatives of l-Pro. The best substrate identified to date is N-propionyl-l-Pro with a value of kcat/Km of 1 × 105 M-1 s-1. Three-dimensional structures of both proteins were determined by X-ray diffraction methods (PDB codes 3MKV and 3FEQ). These proteins fold as distorted (β/α) 8-barrels with two divalent cations in the active site. The structure of Sgx9260c was also determined as a complex with the N-methylphosphonate derivative of l-Pro (PDB code 3N2C). In this structure the phosphonate moiety bridges the binuclear metal center, and one oxygen atom interacts with His-140. The α-carboxylate of the inhibitor interacts with Tyr-231. The proline side chain occupies a small substrate binding cavity formed by residues contributed from the loop that follows β-strand 7 within the (β/α)8-barrel. A total of 38 other proteins from cog1228 are predicted to have the same substrate profile based on conservation of the substrate binding residues. The structure of an evolutionarily related protein, Cc2672 from Caulobacter crecentus, was determined as a complex with the N-methylphosphonate derivative of l-arginine (PDB code 3MTW).
Piperidine is preferred to morpholine for Fmoc cleavage in solid phase glycopeptide synthesis as exemplified by preparation of glycopeptides related to HIV gp120 and mucins
Vuljanic, Tatjana,Bergquist, Karl-Erik,Clausen, Henrik,Roy, Sarbani,Kihlberg, Jan
, p. 7983 - 8000 (2007/10/03)
Protected derivatives of the Tn antigens [Fmoc-Ser/Thr(Ac3GalNAcα)-OH, compounds 5 and 8] have been prepared by glycosylation of Fmoc-Ser/Thr- OAllyl with 3,4,6-tri-O-acetyl-2-azido-2-deoxy-D-galactopyranosyl chloride (2), followed by conversion of the azido group to an acetamide and deallylation. The derivatives 5 and 8 were used for solid phase synthesis of glycopeptides related to HIV gp120 and mucins. In these syntheses piperidine was found to give efficient Fmoc removal whereas deprotection with morpholine was slow and incomplete for some steps. In contrast to previous concerns β- elimination and epimerization of glycopeptide stereocenters was not encountered when piperidine was used for Fmoc deprotection. However, it was found that for glycopeptides which contained cysteine residues, de-O- acetylation with methanolic ammonia had to be performed before side-chain deprotection and cleavage from the solid phase.
