共查询到19条相似文献,搜索用时 187 毫秒
1.
血红蛋白片段的合成及生物活性 总被引:1,自引:0,他引:1
采用多肽固相合成方法, 以Wang 树脂为载体, Fmoc为N-端氨基酸保护基, HOBt-HBTU为缩合试剂, 合成了一系列血红蛋白α链的片段, 产物经RP-HPLC和质谱进行了确定. 生物活性研究结果表明, 该系列多肽具有较高的血管紧张素Ⅰ转换酶抑制活性, 但不具有α-葡萄糖苷酶抑制活性. 相似文献
2.
Fmoc保护氨基酸与Wang树脂的缩合反应 总被引:1,自引:0,他引:1
研究了保护氨基酸、Wang 树脂取代度、树脂粒度、搅拌方式对Fmoc-氨基酸-Wang树脂连接效率的影响. 结果表明, 保护氨基酸分子量的大小会因产生不同的位阻而影响缩合反应的效率, 分子量越小缩合效率越高; Wang树脂的取代度较高时, 已缩合的氨基酸给后续保护氨基酸的缩合形成阻碍, 使缩合效率降低; 粒径较小和搅拌较好时, 对保护氨基酸的粒内外扩散有利, 可提高反应速度和缩合效率. 相似文献
3.
固相合成胸腺五肽(TP5) 总被引:3,自引:0,他引:3
采用Fmoc固相多肽合成中的活化酯方法和2,6-二氯苯甲酰氯(DCB)混合酸酐法, 对Fmoc-Tyr(t-Bu)-OH与Wang树脂反应中的反应级数和表观活化能进行了研究, 并采用常规方法和微波强化方法分别进行了胸腺五肽的合成. 实验结果表明, 活化酯方法的反应级数为1.855, 表观活化能15.24 kJ/mol, 混合酸酐法的表观活化能为35.14 kJ/mol. 与传统方法相比, 微波将缩合反应速率提高了30倍以上, 氨基酸过量倍数也从传统的三倍降低到两倍. 相似文献
4.
在固相多肽合成中,Dmab作为羧基保护基具有脱保护条件温和、步骤简便、选择性高的特点,但有时脱保护效率并不稳定.为此,基于Fmoc/t Bu/Dmab三维正交保护策略,利用固相多肽合成技术设计并合成了4个肽树脂,对固相多肽合成中Glu和Asp主链和侧链羧基的Dmab保护基脱除规律进行了研究.结果显示,树脂上α-ODmab的脱保护快速、完全,β-ODmab和γ-ODmab脱保护反应较慢,可以检测到相应的中间产物(4-氨基苄酯肽),推测脱保护效率由快到慢依次为α-ODmabβ-ODmabγ-ODmab.该结果表明Dmab作为α-COOH保护基具有较高的应用价值,但用于β-COOH和γ-COOH保护时,其脱保护条件尚不成熟. 相似文献
5.
6.
7.
8.
以获得侧链全保护的多肽为总目标,选择接入溴乙酰基把手的Wang树脂作为固相载体,采用多肽固相合成法制备了3种模型肽,将其用于对具有弱碱性和强亲核性的肟盐类裂解剂的研究;设计并制备了5种不同结构的肟铯盐,将其用于模型肽的裂解,并选择综合效果最好的2-吡啶甲醛肟铯盐进行裂解条件的优化.结果表明,肟铯盐类裂解剂可以温和、高效地裂解模型肽,得到侧链全保护的多肽. 相似文献
9.
10.
采用固相合成方法,以Rink Amide树脂为载体,Fmoc保护氨基酸为原料,经苯并三唑-1-四甲基六氟磷酸酯(HBTU)/N,N-二异丙基乙胺(DIEA)缩合,三氟乙酸/苯甲硫醚/乙二硫醇/苯甲醚裂解体系脱除保护基制得IB-367线性肽(4); 4经双氧水氧化制得IB-367一环肽(5); 5经碘乙醇溶液氧化合成抗菌肽IB-367(6),收率34.1%,纯度>95.0%,其结构经MS(ESI)和氨基酸组成分析确证。抑菌活性研究结果表明:6对大肠杆菌和金黄色葡萄球菌的最小抑菌浓度为5.0 μg·mL-1。 相似文献
11.
Liang Z. Yan 《Tetrahedron letters》2004,45(5):923-925
A general method was developed for the synthesis of serine or threonine containing cyclic peptides utilizing the β-hydroxyl side-chain of these residues as an anchor point to Wang resin. The peptide chain was assembled by conventional Fmoc/tBu solid-phase chemistry followed by palladium catalyzed exposure of the allyl protected C-terminus group and on-resin cyclization. The cyclic heptapeptide stylostatin 1 was prepared to demonstrate the utility of this technique. 相似文献
12.
A solid-phase method for the preparation of C-terminal amino-alcohol-containing peptides using activated Wang resin is presented. A diverse set of (fluorenylmethoxy)carbonyl (Fmoc) protected amino alcohols was found to load rapidly and efficiently. The synthetic utility of this approach was demonstrated through the direct synthesis of the peptide drug octreotide with excellent yield and purity. These results suggest that the use of trichloroacetimidate activated resins offers an attractive alternative in the preparation of this class of peptides. 相似文献
13.
In one of the peptide condensation methods termed thioester method, an amino protecting group is required in the lysine side chain. In this study, to investigate the efficiency of the pyruvoyl group as an amino protecting group, we synthesized Nα-fluorenylmethoxycarbonyl (Fmoc)-Nε-pyruvoyl-lysine and introduced it into peptides and glycopeptides by the ordinary Fmoc-based solid phase peptide synthesis. The pyruvoyl peptide could be condensed with a peptide thioester by the thioester method, and this protecting group was easily removed by o-phenylenediamine treatment without significant side reactions. 相似文献
14.
WenHaoWANG XiaoMinZOU XinZHANG YiQiuFU PingXU 《中国化学快报》2005,16(5):585-588
Peptide nucleic acids (PNA) oligomers were synthesized in most cases by peptide a peptide synthesis from N-protected monomers. In this work a new method of obtaining PNA monomer by Ugi four-component condensation reaction was tested by solid-phase synthesis. The Fmoc protected PNA monomer was build up with thymin-l-yl acetic acid, 3-methylbutyl aldehyde, Fmoc protected aminoethyl isocyanide and Gly-Wang resin. 相似文献
15.
We report the synthesis of Fmoc protected single amino acid chelates (SAAC) and their metal complexes. The modified amino acids are suitable for solid-phase peptide synthesis. The use of 4-hydroxymethylbenzoic acid AM (HMBA-AM) resin allows the nucleophilic cleavage of the peptide-metal complexes from the resin without decomplexation. 相似文献
16.
In this Letter, eight tuftsin analogues, seven of which are novel, are presented. All the linear tuftsin analogues contain an isopeptide bond. Modification of the tuftsin chain was based on the introduction of simple amino acids such as valine, glycine, alanine and β-alanine into the peptide chain at the ε-amino group of lysine. The peptides were synthesized by a solid-phase method using the standard Fmoc procedure. Simultaneous deprotection of the peptide side chain and liberation from the resin was achieved using TFA, and the free novel tuftsin analogues were purified and characterized. 相似文献
17.
Dominique Lelièvre 《Tetrahedron letters》2008,49(25):4016-4019
In the course of the chemical synthesis of human protein mitogaligin, we present here a simple method to prepare peptide thioesters using Fmoc chemistry. The hydroxyl side chain of serine was reacted with a trichloroacetimidate Wang resin to anchor it on solid phase. After peptide elongation and orthogonal unmasking of the C-terminus, the amino thioester was introduced under optimized conditions to avoid epimerization. 相似文献
18.
Chenxi Jia Wei Qi Zhimin He Haoming Yang Bin Qiao 《Central European Journal of Chemistry》2006,4(2):285-298
Two heptapeptides have been prepared by Fmoc methodology using Wang resin as solid support. For attachment of the first amino
acid, several coupling systems were evaluated, and DIC/DMAP system could give yields of >99% and low levels of racemization.
The selection of scavenger combination to deprotect side chains revealed that H2O/p-cresol was good at scavenging trityl and 1,2-ethanedithiol was highly efficient for scavenging t-butyl. Through shortening
the preactivation time to 5 min, the racemization which occurred during formation of amide bonds coupled by HBTU was minimized.
The crude peptides were characterized by RP-HPLC and MS, and sequenced by MS/MS to acquire reliable amino acid sequence information. 相似文献
19.
The protected peptide segments corresponding to the sequences 35–43 and 32–34 of toxin II of the scorpion Androctonus australis Hector have been synthesized on a
-alkoxybenzyl ester resin using the base-labile Fmoc -amino protection and HF-labile side chain protecting groups. Crude peptides obtained after trifluoroacetic acid cleavage have been purified by solvent extraction, dimethylacetamide-water precipitation and semi-preparative reversed phase HPLC. Both synthetic and purification protocols have been optimized for good yields and high purity. Fast atom bombardment mass spectrometry has proved to be a very useful technique to characterize protected peptide segments. 相似文献