共查询到20条相似文献,搜索用时 15 毫秒
1.
ShengLiCAO HuaFU YuFenZHAO 《中国化学快报》2005,16(3):317-320
H-phosphonates were conveniently prepared by direct transesterification of diphenyl phosphite (DPP) with the corresponding alcohols, without further purification they were reacted with branched peptide methyl ester (L-Leu2-L-LysOMe) through Atherton-Todd method, a series of different substituted alkyloxy (N-phosphoryl-L-Leu)2-L-LysOMe were synthesized, and their stmctures were confirmed by ^31P NMR, ESI-MS, ^1H NMR, ^13C NMR, IR and elemental analysis. The approach possesses the advantages of easy operation, high yield and inexpensive phosphorylating reagent. 相似文献
2.
Sheng Li CAO Yu Yang JIANG Yu Ping FENG Yan Ling NIU Yu Fen ZHAO* Key Laboratory of Bioorganic Phosphorus Chemistry Ministry of Education Department of Chemistry Tsinghua University Beijing Department of Chemistry Capital Normal University Beijing 《中国化学快报》2003,14(4)
Much research has shown that some N-phosphoryl peptides are endowed with important biological activities. For instance, Na-(diaryloxyphosphoryl)-L-alanyl-L-prolines are moderate inhibitors of angiotensin converting enzyme and yield highly potent inhibitors when they hydrolyze under physiological condition lossing 1 mol phenol1; Phosphoramido (N-[(a-rhamnopyranosyloxy)hydroxyphosphinyl]-L-Leu-L-Trp) and its analogues have been shown to be inhibitors of endothelin converting enzyme, therefor… 相似文献
3.
Ulrich Reineke Jens Schneider-Mergener 《Angewandte Chemie (International ed. in English)》1998,37(6):769-771
A short peptide as mimic for the hemopoietic growth factor erythropoietin (containing 165 amino acids) could be identified with the aid of peptide libraries on phage surfaces (phage display). The crystal structure of a peptide dimer complexed with two erythropoietin receptors (shown on the right) provides an insight into the molecular basis of this protein mimicry. 相似文献
4.
W. Mathis Rink Dr. Franziska Thomas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1665-1677
Coiled coils (CCs) are well-understood protein-folding motifs. They appear in a variety of oligomer states and as homo- and heteromeric assemblies. This versatility and the general accessibility by de novo design makes them ideal building blocks for synthetic biology. This Minireview highlights the efforts being made in designing small peptide catalysts or reaction templates based on the CC scaffold. The first reports described autocatalysis or mediation of peptide ligation based on CC recognition. Over the years, the designs became more advanced, catalyzing ester hydrolysis, acyl transfer and redox reactions with partial enzyme-like reactivity. Due to the ability to control CC assembly, and, in heterodimeric systems, the association and dissociation, the CC motif has become a common peptide tag in chemical biology. 相似文献
5.
Haruo Matsuyama Nobuhiro Itoh Masato Yoshida Masahiko Iyoda 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):475-476
(S)- and (R)-β-amino acid derivatives were synthesized by the asymmetric conjugate addition of ammonia and piperidazine to t-butyl (E)-2-[(R)- and (S)-p-tolylsulfinyl]cinnamates, respectively. 相似文献
6.
Dr. Manuel G. Ricardo Dr. Ameena M. Ali Dr. Jacek Plewka Dr. Ewa Surmiak Dr. Beata Labuzek Prof. Constantinos G. Neochoritis Jack Atmaj Dr. Lukasz Skalniak Ran Zhang Prof. Tad A. Holak Prof. Matthew Groves Prof. Daniel G. Rivera Prof. Alexander Dömling 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5273-5279
Stapled peptides are chemical entities in-between biologics and small molecules, which have proven to be the solution to high affinity protein–protein interaction antagonism, while keeping control over pharmacological performance such as stability and membrane penetration. We demonstrate that the multicomponent reaction-based stapling is an effective strategy for the development of α-helical peptides with highly potent dual antagonistic action of MDM2 and MDMX binding p53. Such a potent inhibitory activity of p53-MDM2/X interactions was assessed by fluorescence polarization, microscale thermophoresis, and 2D NMR, while several cocrystal structures with MDM2 were obtained. This MCR stapling protocol proved efficient and versatile in terms of diversity generation at the staple, as evidenced by the incorporation of both exo- and endo-cyclic hydrophobic moieties at the side chain cross-linkers. The interaction of the Ugi-staple fragments with the target protein was demonstrated by crystallography. 相似文献
7.
α-Boc-amino-Fmoc-glycine 6 was prepared in two steps from 9-fluorenyl-methylcarbamate 1, glyoxylic acid 3 and t-butyl carbamate 5. This compound is useful in Solid Phase Peptide Synthesis to prepare α-aminoglycine-containing peptides using Fmoc-strategy. 相似文献
8.
ShengLiCAO YuYangJIANG YuPingFENG YanLingNIU YuFenZHAO 《中国化学快报》2003,14(4):343-346
A series of N-phosphoryl branched peptides were synthesized by coupling of various N-phosphoryl amino acids to L-Lysine methyl ester,and their structures were confirmed by ^31PNMR,^1H NMR,MS and elemental analysis.The results of cell biological tests indicated that compound 1d and 1e obviously inhibites the growth of both k562 and A2780 cells. 相似文献
9.
Dr. Mathis Baalmann Laura Neises Sebastian Bitsch Hendrik Schneider Lukas Deweid Philipp Werther Nadja Ilkenhans Martin Wolfring Michael J. Ziegler Jonas Wilhelm Prof. Dr. Harald Kolmar Dr. Richard Wombacher 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12985-12993
Bioorthogonal chemistry holds great potential to generate difficult-to-access protein–protein conjugate architectures. Current applications are hampered by challenging protein expression systems, slow conjugation chemistry, use of undesirable catalysts, or often do not result in quantitative product formation. Here we present a highly efficient technology for protein functionalization with commonly used bioorthogonal motifs for Diels–Alder cycloaddition with inverse electron demand (DAinv). With the aim of precisely generating branched protein chimeras, we systematically assessed the reactivity, stability and side product formation of various bioorthogonal chemistries directly at the protein level. We demonstrate the efficiency and versatility of our conjugation platform using different functional proteins and the therapeutic antibody trastuzumab. This technology enables fast and routine access to tailored and hitherto inaccessible protein chimeras useful for a variety of scientific disciplines. We expect our work to substantially enhance antibody applications such as immunodetection and protein toxin-based targeted cancer therapies. 相似文献
10.
Dr. Marcel Leroux Wan-Yun Huang Yannick Lemke Thaddäus J. Koller Prof. Dr. Konstantin Karaghiosoff Prof. Dr. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(41):8951-8957
Chiral β-aminoalkylzinc halides were prepared starting from optically pure commercial β-amino-alcohols. These amino-alcohols were converted to the corresponding N-pyrrolyl-protected alkyl iodides which undergo a zinc insertion in the presence of LiCl (THF, 25 °C, 10–90 min). Subsequent Negishi cross-coupling or acylation reactions with acid chlorides produced amino-derivatives with retention of chirality. Diastereoselective CBS-reductions of some prepared N-pyrrolyl-ketones provided 1,3-subsituted N-pyrrolyl-alcohols with high diastereoselectivity. Additionally, a deprotection procedure involving an ozonolysis allowed the conversion of the pyrrole-ring into a formamide without loss of optical purity. 相似文献
11.
Watanabe N Hamano M Todaka S Asaeda T Ijuin HK Matsumoto M 《The Journal of organic chemistry》2012,77(1):632-639
Diphenylparabanic acid was found to react with >2 equiv of organolithiums at -78 °C to effectively give the corresponding symmetrical α-diketones. However, upon treatment with 1 equiv of organolithium, the parabanic acid gave mainly 5-substituted 5-hydroxyimidazolidine-2,4-diones. On the other hand, Grignard reagents were less reactive toward the parabanic acid at low temperature, and selectively gave the corresponding 5-hydroxyimidazolidine-2,4-diones even if more than 1 equiv of the reagents was used. A tandem process in which the parabanic acid was first reacted with a Grignard reagent and then reacted in one-pot with an organolithium effectively gave the unsymmetrical α-diketone. 5-Substituted 5-hydroxyimidazolidine-2,4-diones were useful as versatile precursors for preparing α-ketocarboxylic acids as well as unsymmetrical α-diketones. 相似文献
12.
Ashley E. Truxal Dr. Liping Cao Prof. Dr. Lyle Isaacs Prof. Dr. David E. Wemmer Prof. Dr. Alexander Pines 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(24):6108-6112
Advancement of hyperpolarized 129Xe MRI technology toward clinical settings demonstrates the considerable interest in this modality for diagnostic imaging. The number of contrast agents, termed biosensors, for 129Xe MRI that respond to specific biological targets, has grown and diversified. Directly functionalized xenon-carrying macrocycles, such as the large family of cryptophane-based biosensors, are good for localization-based imaging and provide contrast before and after binding events occur. Noncovalently functionalized constructs, such as cucurbituril- and cyclodextrin-based biosensors, benefit from commercial availability and optimal exchange dynamics for CEST imaging. In this work, we report the first directly functionalized cucurbituril used as a xenon biosensor. Biotinylated cucurbit[7]uril (btCB7) gives rise to a 129Xe hyperCEST response at the unusual shift of δ=28 ppm when bound to its protein target with substantial CEST contrast. We posit that the observed chemical shift is due to the deformation of btCB7 upon binding to avidin, caused by proximity to the protein surface. Conformational searches and molecular dynamics (MD) simulations support this hypothesis. This construct combines the strengths of both families of biosensors, enables a multitude of biological targets through avidin conjugation, and demonstrates the advantages of functionalized cucurbituril-based biosensors. 相似文献
13.
T. Hashimoto Y. Uezu F. Ishizuka H. Washio 《Journal of Radioanalytical and Nuclear Chemistry》1993,173(1):87-97
A selective extraction of the correlated events due to three kinds of short-lived -decay events,216Po (145 ms),217At (32.3 ms) and215Po (1.78 ms), from other random background events were examined by using a time interval analysis (TIA) from the viewpoint of detection sensitivity. In the theoretical treatment based on the probability and statistics, it was clarified that the detection sensitivity proportionally increased with shortening half-lives in the following order,215Po>217At>216Po. In the experiments, pulses from a liquid scintillator owing to -decay events were analyzed using a multiple TIA technique and resulted in the highest sensitivity of219Rn–215Po pairs in the actinium series. Thus, the multiple TIA method was applied to the practical determination of219Rn–215Po pairs in natural samples. 相似文献
14.
The reactions of the tert-butyldimethylsilylated acyloins of five-, six- and seven-membered rings with the lithium reagents of benzyltrimethylsilane, thiophenoxymethyltrimethylsilane and tri-methylsilyl acetonitrile were studied. These reactions favor formation of the substituted (Z) exo methylidene silyl ethers in moderate yields. 相似文献
15.
The tin-lithium exchange and the palladium-catalized coupling reactions of the title compounds have been studied. The latter reaction was found to be more efficient for functionalizing the α-carbon of these esters. 相似文献
16.
Santi M. Mandal Ludovico Migliolo Octavio L. Franco 《Journal of the American Society for Mass Spectrometry》2012,23(11):1939-1948
Several methods have been proposed for determining the binding affinity of antimicrobial peptides (AMPs) to bacterial cells. Here the utilization of MALDI-TOF-MS was proposed as a reliable and efficient method for high throughput AMP screening. The major advantage of the technique consists of finding AMPs that are selective and specific to a wide range of Gram-negative and -positive bacteria, providing a simple reliable screening tool to determine the potential candidates for broad spectrum antimicrobial drugs. As a prototype, amp-1 and -2 were used, showing highest activity toward Gram-negative and -positive membranes respectively. In addition, in silico molecular docking studies with both peptides were carried out for the membranes. In silico results indicated that both peptides presented affinity for DPPG and DPPE phospholipids, constructed in order to emulate an in vivo membrane bilayer. As a result, amp-1 showed a higher complementary surface for Gram-negative while amp-2 showed higher affinity to Gram-positive membranes, corroborating MS analyses. In summary, results here obtained suggested that in vitro methodology using MALDI-TOF-MS in addition to theoretical studies may be able to improve AMP screening quality. 相似文献
17.
Miroslava Martinková Jozef Gonda Jana Špaková Raschmanová Juraj Kuchár Jozef Kožíšek 《Tetrahedron: Asymmetry》2012,23(8):536-546
A synthetic route to the protected quaternary α-amino acid 2 with a hydroxylated side chain has been achieved. The key transformations are the diastereoselective substrate-controlled epoxidation of allylic alcohol 4; a highly stereoselective oxidation–reduction protocol, and the excellent regioselective isomerization of the oxazolidinone ring to give an oxazinanone skeleton in derivative 3. The carboxylic acid 2 obtained represents the polar substructure, which is present in myriocin 1. 相似文献
18.
《Tetrahedron: Asymmetry》1999,10(22):4277-4280
Constrained camphor-derived oxazaphospholanes have provided an efficient entry for the preparation of enantiomerically enriched α-chlorophosphonic acids. 相似文献
19.
The role of metal ions in Alzheimer's disease etiology is unresolved. For the redox-active metal ions iron and copper, the formation of reactive oxygen species by metal amyloid complexes has been proposed to contribute to Alzheimer's disease neurodegeneration. For copper, reactive oxygen species are generated by copper redox cycling between its 1+ and 2+ oxidation states. Thus, the AβCu(I) complex is potentially a critical reactant associated with Alzheimer's disease etiology. Through competitive chelation, we have measured the affinity of the soluble copper-binding domain of the amyloid-β peptide for Cu(I). The dissociation constants are in the femtomolar range for both wild-type and histidine-to-alanine mutants. These results indicate that Cu(I) binds more tightly to monomeric amyloid-β than Cu(II) does, which leads us to propose that Cu(I) is a relevant in vivo oxidation state. 相似文献
20.
Prof. Dr. Barry M. Trost Jacob S. Tracy Tas Yusoontorn Chao-I Joey Hung 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2390-2394
The preparation of acyclic β-fluoro amines bearing tetrasubstituted fluorine stereocenters is described via a direct Zn/ProPhenol-catalyzed Mannich reaction. The reaction utilizes branched vinyl or alkynyl α-fluoro ketones that can be coupled with a range of aryl, heteroaryl, vinyl, or cyclopropyl aldimines in high yield and with excellent diastereo- (up to >20:1) and enantioselectivity (up to 99 %). The use of readily cleaved tert-butoxycarbonyl (Boc) or carboxybenzyl (Cbz) imine protecting groups adds utility to the reaction by allowing for easy access to the free amine products under mild and chemoselective reaction conditions. 相似文献