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1.
Koki Hasegawa Yin Lin Sha Jeong Kyu Bang Toru Kawakami Kenichi Akaji Saburo Aimoto 《Letters in Peptide Science》2001,8(3-5):277-284
Efficient methods for the preparation of phosphopeptidethioesters were examined, using Fmoc-based solid-phase method.Phosphopeptide thioesters were obtained in good yields by theuse of 1-methylpyrrolidine, hexamethyleneimine and 1-hydroxybenzotriazole in a DMSO-DMF (1:1, v/v) solution fordeblocking the Fmoc groups. Epimerization, which is oftenobserved at the C-terminal amino acid, was effectivelysuppressed by shortening the time of deblocking process viathe use of highly base sensitive Fmoc(2-F) groups for -aminoprotection. 相似文献
2.
Escher Sylvia E. Klüver Enno Adermann Knut 《International journal of peptide research and therapeutics》2001,8(6):349-357
Summary The CC chemokine CCL14/HCC-1(9–74), a 66-residue polypeptide containing two disulfide bonds, was recently discovered from
a human hemofiltrate peptide library as a high-affinity ligand of the chemokine receptors CCR1 and CCR5. It has been shown
to inhibit HIV infection by blocking CCR5. Using Fmoc methodology, we, report the chemical synthesis of CCL14/HCC-1 by conventional
stepwise solid-phase peptide synthesis (SPPS) and, alternatively, native chemical ligation. To optimize SPPS of CCL14/HCC-1,
difficult sequence regions were identified by mass spectrometry, in order to obtain a crude tetrathiol precursor suitable
for oxidative disulfide formation. For synthesis of CCL14/HCC-1 by native chemical ligation, the peptide was divided into
two segments, CCL14/HCC-1(9–39) and CCL14/HCC-1(40–74), the latter containing a cysteine residue at the amino-terminus. The
synthesis of the thioester segment was carried out comparing a thiol linker with a sulfonamide safety-catch linker. While
the use of the thiol linker led to very low overall yields of the desired thioester, the sulfonamide linker was efficient
in obtaining the 31-residue thioester of CCL14/HCC-1(9–39), suggesting a superior suitability of this linker in generating
larger thioesters using Fmoc chemistry. The thioester of CCL14/HCC-1 was subsequently ligated with the cysteinyl segment to
the full-length chemokine. Disulfides were introduced in the presence of the redox buffer cysteine/cystine. The products of
both SPPS and native chemical ligation were identical. The use of a sulfonamide safety-catch linker enables the Fmoc synthesis
of larger peptide thioesters, and is thus useful to generate arrays of larger polypeptides. 相似文献
3.
The CC chemokine CCL14/HCC-1(9-74), a 66-residue polypeptide containing two disulfide bonds, was recently discovered from a human hemofiltrate peptide library as a high-affinity ligand of the chemokine receptors CCR1 and CCR5. It has been shown to inhibit HIV infection by blocking CCR5. Using Fmoc methodology, we report the chemical synthesis of CCL14/HCC-1 by conventional stepwise solid-phase peptide synthesis (SPPS) and, alternatively, native chemical ligation. To optimize SPPS of CCL14/HCC-1, difficult sequence regions were identified by mass spectrometry, in order to obtain a crude tetrathiol precursor suitable for oxidative disulfide formation. For synthesis of CCL14/HCC-1 by native chemical ligation, the peptide was divided into two segments, CCL14/HCC-1(9-39) and CCL14/HCC-1(40-74), the latter containing a cysteine residue at the amino-terminus. The synthesis of the thioester segment was carried out comparing a thiol linker with a sulfonamide safety-catch linker. While the use of the thiol linker led to very low overall yields of the desired thioester, the sulfonamide linker was efficient in obtaining the 31-residue thioester of CCL14/HCC-1(9-39), suggesting a superior suitability of this linker in generating larger thioesters using Fmoc chemistry. The thioester of CCL14/HCC-1 was subsequently ligated with the cysteinyl segment to the full-length chemokine. Disulfides were introduced in the presence of the redox buffer cysteine/cystine. The products of both SPPS and native chemical ligation were identical. The use of a sulfonamide safety-catch linker enables the Fmoc synthesis of larger peptide thioesters, and is thus useful to generate arrays of larger polypeptides. 相似文献
4.
A new method was developed for the synthesis of peptide thioesters from free amino acids and thiols in water. This one-pot
simple method involves two steps: (1) activation in water of an amino acid presumably as its N-carboxyanhydride (NCA) using 1,1′-carbonyldiimidazole (CDI), and (2) subsequent condensation of the activated amino acid-NCA
in the presence of a thiol. With this method citrulline peptide thioesters containing up to 10 amino acid residues were prepared
in a single reaction. This aqueous synthetic method provides a simple way to prepare peptide thioesters for studies of peptide
replication involving ligation of peptide thioesters on peptide templates. The relevance of peptide replication to the origin-of-life
process is supported by previous studies showing that amino acid thioesters (peptide thioester precursors) can be synthesized
under prebiotic conditions by reaction of small sugars with ammonia and a thiol. 相似文献
5.
Native chemical ligation is widely used for the convergent synthesis of proteins. The peptide thioesters required for this process can be challenging to produce, particularly when using Fmoc‐based solid‐phase peptide synthesis. We have previously reported a route to peptide thioesters, following Fmoc solid‐phase peptide synthesis, via an N→S acyl shift that is initiated by the presence of a C‐terminal cysteine residue, under mildly acidic conditions. Under typical reaction conditions, we occasionally observed significant thioester hydrolysis as a consequence of long reaction times (~48 h) and sought to accelerate the reaction. Here, we present a faster route to peptide thioesters, by replacing the C‐terminal cysteine residue with selenocysteine and initiating thioester formation via an N→Se acyl shift. This modification allows thioester formation to take place at lower temperatures and on shorter time scales. We also demonstrate how application of this strategy also accelerates peptide cyclization, when a linear precursor is furnished with an N‐terminal cysteine and C‐terminal selenocysteine. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
6.
Ken'ichiroh Nakamura Tomoki Kanao Tomoya Uesugi Toshiaki Hara Takeshi Sato Toru Kawakami Saburo Aimoto 《Journal of peptide science》2009,15(11):731-737
An efficient method of peptide thioester synthesis is described. The reaction is based on an N‐4,5‐dimethoxy‐2‐mercaptobenzyl (Dmmb) auxiliary‐assisted N‐S acyl shift reaction after assembling a peptide chain by Fmoc‐solid phase peptide synthesis. The Dmmb‐assisted N‐S acyl shift reaction proceeded efficiently under mildly acidic conditions, and the peptide thioester was obtained by treating the resulting S‐peptide with sodium 2‐mercaptoethanesulfonate. No detectable epimerization of the amino acid residue adjacent to the thioester moiety in the case of Leu was found. The reactions were also amenable to the on‐resin preparation of peptide thioesters. The utility was demonstrated by the synthesis of a 41‐mer peptide thioester, a phosphorylated peptide thioester and a 33‐mer peptide thioester containing a trimethylated lysine residue. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
7.
Stevenson Flemer Jr 《Journal of peptide science》2009,15(11):693-696
A straightforward and convenient protocol is presented for the direct thioesterification of fully protected peptide C‐terminal carboxylates synthesized by Fmoc strategy. This methodology specifically serves to overcome the frequent insolubility problem of these fully protected carboxolate isolates during the thioesterification process by carrying out the reaction as an in situ procedure on the freshly cleaved 1% TFA/DCM solution of carboxylate. The direct thioesterification of a number of insolubility prone peptide systems is explored and compared with some control systems for ease of conversion to the corresponding thioesters. It is shown that although the fully protected carboxylates are indeed insoluble to varying degrees in the thioesterification reactions carried out using the classical approach, full dissolution is maintained and complete conversion is evident using the in situ methodology. This protocol serves to remove a frequent stumbling block in the preparation of peptide thioesters via the direct approach, allowing for facile entry into previously difficult systems traditionally unapproachable through this method. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
8.
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·Et2O) under microwave irradiation. The products are useful building blocks for the synthesis of glycopeptides. 相似文献
9.
Today, Fmoc SPPS is the method of choice for peptide synthesis. Very‐high‐quality Fmoc building blocks are available at low cost because of the economies of scale arising from current multiton production of therapeutic peptides by Fmoc SPPS. Many modified derivatives are commercially available as Fmoc building blocks, making synthetic access to a broad range of peptide derivatives straightforward. The number of synthetic peptides entering clinical trials has grown continuously over the last decade, and recent advances in the Fmoc SPPS technology are a response to the growing demand from medicinal chemistry and pharmacology. Improvements are being continually reported for peptide quality, synthesis time and novel synthetic targets. Topical peptide research has contributed to a continuous improvement and expansion of Fmoc SPPS applications. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
10.
Ciapetti Paola Mann André Schoenfelder Angèle Taddei Maurizio Trifilieff Elisabeth Canet Isabelle Canet Jean Louis 《International journal of peptide research and therapeutics》1997,4(4-6):341-349
Summary Due to the increasing interest in the use of oligonucleotide analogues as antisense and antigene drugs, we designed a chiral
analogue constituted of a peptidic frame bearing nucleobases in suitable positions (C-PNA). We recently reported the synthesis
of four nonnatural α-amino acids with the DNA bases in the lateral chain. In this paper we present an improved synthesis of
the Fmoc monomers and their polymerisation to polypeptidic oligonucleotide analogues using a modification of the standard
protocol for solid phase peptide synthesis. 相似文献
11.
Silyl linker-based approach to the solid-phase synthesis of Fmoc glycopeptide thioesters 总被引:1,自引:0,他引:1
Ishii A Hojo H Nakahara Y Ito Y Nakahara Y 《Bioscience, biotechnology, and biochemistry》2002,66(2):225-232
An efficient solid-phase synthesis of Fmoc (glyco)peptide thioesters is described. Fmoc x Ser x OAll and Fmoc x Thr x OAll bound to resin with a silyl ether linker were deallylated by Pd(0) catalysis and condensed with thiophenol, benzyl mercaptane, and ethyl 3-mercaptopropionate by activation with DCC/HOBt. The thioesters were released from the resin either by treatment with CsF-AcOH or by acidic hydrolysis. The effectiveness of this silyl linker strategy is further demonstrated by the synthesis of more complex (glyco)peptide thioesters 25, 26 and 27 involving N-->C and C-->N peptide elongation. 相似文献
12.
A side-chain anchoring approach for preparation of peptide thioesters by Fmoc SPPS is reported. This strategy involves the side-chain anchoring of trifunctional amino acids, such as Lys, Glu, Gln, Asp and Asn, for peptide elongation and the post-chain assembly introduction of thioester functionality. This approach allows for the use of standard nucleophilic Fmoc peptide synthesis cycles, which are generally incompatible with thioester-based resin-linkages. The strategy was successfully demonstrated by the straightforward Fmoc syntheses of a model RANTES(1--33) thioester peptide. The Fmoc prepared RANTES(1--33) thioester peptide was then ligated to RANTES(34--68), folded and purified to give the RANTES protein. 相似文献
13.
The sequence dependence of base-catalysed aspartmide formation during Fmoc-based SPPS was systematically studied employing the peptide models H-Val-Lys-Asp-Xaa-Tyr-Ile-OH. The extent of formation of aspartimide and related by-products was determined by RP-HPLC. Considerable amounts of by-products were formed in the case of Xaa = Asp(OtBu), Arg(Pbf), Asn(Mtt), Cys(Acm) and unprotected Thr. Aspartimide formation could be diminished by incorporation of Asp(OMpe) or by employing milder methods for Fmoc cleavage, e.g. hexamethyleneimine/N-methylpyrrolidine/HOBt/NMP/DMSO 4:50:4:71:71 (v/v/w/v/v). 相似文献
14.
Summary We have examined the sequence dependence of aspartimide formation during Fmoc-based solid-phase synthesis of the peptide Val-Lys-Asp-X-Tyr-Ile. The extent of aspartimide formation and subsequent conversion to the - or -piperidide was characterized and quantitated by analytical reversed-phase high-performance liquid chromatography and fast atom bombardment mass spectrometry. Aspartimide formation occurred for X=Arg(Pmc), Asn(Trt), Asp(OtBu), Cys(Acm), Gly, Ser, Thr and Thr(tBu). No single approach was found that could inhibit this side reaction for all sequences. The most effective combinations, in general, for minimization of aspartimide formation were (i) tert-butyl side-chain protection of aspartate, piperidine for removal of the Fmoc group, and either 1-hydroxybenzotriazole or 2,4-dinitrophenol as an additive to the piperidine solution; or (ii) 1-adamantyl side-chain protection of aspartate and 1,8-diazabicyclo[5.4.0]undec-7-ene for removal of the Fmoc group. 相似文献
15.
Ken’ichiroh Nakamura Hiroaki Mori Toru Kawakami Hironobu Hojo Yoshiaki Nakahara Saburo Aimoto 《International journal of peptide research and therapeutics》2007,13(1-2):191-202
The 4,5-dimethoxy-2-mercaptobenzyl (Dmmb) group attached to a main chain amide in a peptide is easily transformed into an
S-peptide via an intramolecular N–S acyl shift reaction under acidic conditions, and the S-peptide produces a peptide thioester through an intermolecular thiol–thioester exchange reaction. In order to develop a method
for efficiently preparing peptide thioesters based on the N–S acyl shift reaction, the factors involved in this process were analyzed in detail. The general features of the transformation
at the Dmmb group attached amide bond in a trifluoroacetic acid (TFA) solution and the generation of a peptide thioester were
examined by 13C-NMR spectral measurements, reversed-phase (RP) HPLC analyses, mass measurements, and amino acid analyses. The methoxy group
of the Dmmb group was not essential for the N–S acyl shift reaction, but played a role in stabilizing the thioester form. The addition of water to the TFA solution accelerated
the N–S acyl shift reaction mediated by the Dmmb group and also suppressed the acid-catalyzed cleavage of the Dmmb group. A peptide
thioester was produced from the S-peptide via an intermolecular thiol–thioester exchange reaction with minimal epimerization of the amino acid residue that constituted
the thioester bond. Undesirable side reactions, such as the hydrolysis of the thioester bond and an S–N acyl shift reaction occurred during the synthetic process, which is a subject of further investigation. 相似文献
16.
Katarina Norén Maria Kempe 《International journal of peptide research and therapeutics》2009,15(4):287-292
The synthesis of multilayered magnetic nanoparticles (MNPs) for use as a support in solid-phase peptide synthesis (SPPS) is
described. Silanization of magnetite (Fe3O4) nanoparticles with 3-(trimethoxysilyl)propyl methacrylate introduced polymerizable groups on the surface. Polymerization
with allylamine, trimethylolpropane trimethacrylate, and trimethylolpropane ethoxylate (14/3 EO/OH) triacrylate provided a
polymeric coating and amino groups to serve as starting points for the synthesis. After coupling of an internal reference
amino acid and a cleavable linker, the coated MNPs were applied as the solid phase during synthesis of Leu-enkephalinamide
and acyl carrier protein (65-74) by Fmoc chemistry. A “high-load” version of the MNP support (0.32 mmol/g) was prepared by
four consecutive cycles of Fmoc-Lys(Fmoc)-OH coupling and Fmoc deprotection. Successful synthesis of Leu-enkephalin was demonstrated
on the “high-load” MNPs. Chemical stability studies proved the particles to be stable under SPPS conditions and magnetization
measurements showed that the magnetic properties of the particles were maintained throughout derivatizations and SPPS. The
MNPs were further characterized by high-resolution transmission electron microscopy, inductively coupled plasma atomic emission
spectrometry, elemental analysis, and nitrogen gas adsorption measurements. 相似文献
17.
Identification and Suppression of β-Elimination Byproducts Arising from the Use of Fmoc-Ser(PO3Bzl,H)-OH in Peptide Synthesis 总被引:1,自引:0,他引:1
Troy J. Attard Neil M. O’Brien-Simpson Eric C. Reynolds 《International journal of peptide research and therapeutics》2009,15(1):69-79
The formation of 3-(1-piperidinyl)alanyl-containing peptides via phosphoryl β-elimination was identified from the application of Fmoc-Ser(PO3Bzl,H)-OH in peptide synthesis as shown by RP-HPLC, ES-MS and 31P-NMR analysis. An N
α
-deprotection study using the model substrates, Fmoc-Xxx(PO3Bzl,H)-Val-Glu(OtBu)-Resin (Xxx = Ser, Thr or Tyr) demonstrated that piperidine-mediated phosphoryl β-elimination occurred in the N-terminal Ser(PO3Bzl,H) residue at a ratio of 7% to the target phosphopeptide, and that this side reaction did not occur in the corresponding
Thr(PO3Bzl,H)- or Tyr(PO3Bzl,H)- residues. The generation of 3-(1-piperidinyl)alanyl-peptides was also shown to be enhanced by the use of microwave
radiation during Fmoc deprotection. An examination of alternative bases for the minimization of byproduct formation showed
that cyclohexylamine, morpholine, piperazine and DBU gave complete suppression of β-elimination, with a 50% cyclohexylamine/DCM (v/v) deprotection protocol providing the crude peptide of highest purity. Piperidine-induced β-elimination was found only to occur in Ser(PO3Bzl,H) residues that were in the N-terminal position, since the addition of the next residue in the sequence rendered the
phosphoseryl residue stable to multiple piperidine treatments. The application of the alternative N
α
-deprotection protocol using 50% cyclohexylamine/DCM (v/v) is therefore recommended for deprotection of the Fmoc group from
the Fmoc-Ser(PO3Bzl,H) residue, with particular benefit anticipated for the synthesis of multiphosphoseryl peptides. 相似文献
18.
Pascal Verdié Gilles Subra Pierre Chevallet Muriel Amblard Jean Martinez 《International journal of peptide research and therapeutics》2007,13(1-2):337-343
As part of our efforts to design constrained peptide mimics and introduce them in peptide sequences, we set up the synthesis
of racemic N-Fmoc protected hydroxypyrrolidine by reduction of the corresponding oxopyrroline. Hydroxypyrrolidines are synthesized
using amino acid building block and β-ketoester via a 4-steps solid supported route on Wang resin beads. The hydroxypyrrolidine template can be seen as a constrained mimic of
statine. As proof of concept, the pseudopeptide JMV 2776, incorporating this new statine mimic has been synthesized. We replaced
the phenyl statine building block in the sequence of known BACE 1/2 inhibitors by 5-benzyl 2-methyl 4-hydroxypyrrolidine,
using conventional Fmoc SPPS on Rink amide PS resin.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Peptide-bond modification via N-hydroxylation has been explored as a strategy for metal coordination to induce conformational rigidity and orient side chains for specific molecular recognition. N-Hydroxyamides were prepared by reacting N-benzyloxyamino acid esters or amides with Fmoc-AA-Cl/AgCN (Fmoc: 9-fluorenylmethoxycarbonyl; AA: amino acid) in toluene or Fmoc-AA/HATU/DIEA in DMF (HATU: O-(7-azabenzotriazol-lyl)-1,1,3,3-tetramethyluronium hexafluorophosphate; DIEA: N,N-diisopropylethylamine; DMF: N,N-dimethylformamide), followed by deblocking of benzyl protecting groups. Novel linear and cyclic N,N'-dihydroxypeptides were efficiently assembled using Fmoc chemistry in solution and/or on a solid support. As screened by electrospray ionization-mass spectroscopy (ESI-MS), high iron-binding selectivity and affinity were attainable. Compounds having a spacer of two alpha-amino acids between the amino acids bearing the two hydroxamates, i.e., a spacer of 8 atoms, generated 1:1 iron complex species in the gas phase. Moreover, high performance liquid chromatography (HPLC), uv/vis, and (1)H-NMR analyses provided direct evidence for complex formations in solution. Significantly, the representative compound cyclo(Leu-Psi[CON(OH)]-Phe-Ala-Pro)(2) (P8) may serve as a robust metal-binding scaffold in construction of a metal-binding library for versatile metal-mediated molecular recognition. 相似文献
20.
Dimethylformamide (DMF), which is still the most commonly used solvent for Fmoc‐SPPS, has the potential for degradation over time on exposure to air (and water vapour) and storage, to give dimethylamine and formic acid impurities. In particular, dimethylamine can lead to unwanted deprotection of the fluorenylmethyloxycarbonyl (Fmoc) group during, for example, the initial loading of Fmoc amino acids in SPPS, which leads reduced calculated loading values. We have found that treatment of such aged DMF by simple sparging with an inert gas (N2), or vacuum sonication, can regenerate the DMF in order to restore loading levels back to those found for newer, fresh, DMF samples. 相似文献