- FRET-based cyanine probes for monitoring ligation reactions and their applications to mechanistic studies and catalyst screening
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There is an ever-increasing need to design better methods to selectively connect two molecules under mild aqueous conditions on a small scale. The process of finding such methods significantly relies on the employment of an appropriate assay. We report here a modular FRET-based assay to monitor such reactions and illustrate how the assay is used to monitor two particular reactions: native chemical ligation (NCL) and oxime ligation. For both reactions we show that by employing appropriately designed probes FRET measurements could be used to monitor the reaction's progress. We additionally demonstrate the usefulness of the developed probe system to study the mechanisms of the ligation reactions, for example, in monitoring the formation of a trimeric intermediate in the NCL reaction. Finally, we demonstrate that FRET measurements conducted in our system allow the quantification of the reaction yield and we show the application of our FRET-based assay to catalyst screening for the oxime ligation.
- Herbst,Shabat
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- Efficient Pictet–Spengler Bioconjugation with N-Substituted Pyrrolyl Alanine Derivatives
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We discovered N-pyrrolyl alanine derivatives as efficient reagents for the fast and selective Pictet–Spengler reaction with aldehyde-containing biomolecules. Other aldehyde-labeling methods described so far have several drawbacks, like hydrolytic instabil
- Pomplun, Sebastian,Mohamed, Mohamed Y. H.,Oelschlaegel, Tobias,Wellner, Christian,Bergmann, Frank
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- Reactivity-dependent PCR: Direct, solution-phase in vitro selection for bond formation
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(Figure Presented) In vitro selection is a key component of efforts to discover functional nucleic acids and small molecules from libraries of DNA, RNA, and DNA-encoded small molecules. Such selections have been widely used to evolve RNA and DNA catalysts
- Gorin, David J.,Kamlet, Adam S.,Liu, David R.
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- Bio-orthogonal Coupling as a Means of Quantifying the Ligand Density on Hydrophilic Quantum Dots
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We describe the synthesis of two metal-coordinating ligands that present one or two lipoic acid (LA) anchors, a hydrophilic polyethylene glycol (PEG) segment and a terminal reactive group made of an azide or an aldehyde, two functionalities with great utility in bio-orthogonal coupling techniques. These ligands were introduced onto the QD surfaces using a combination of photochemical ligation and mixed cap exchange strategy, where control over the fraction of azide and aldehyde groups per nanocrystal can be easily achieved: LA-PEG-CHO, LA-PEG-N3, and bis(LA)-PEG-CHO. We then demonstrate the application of two novel bio-orthogonal coupling strategies directly on luminescent quantum dot (QD) surfaces that use click chemistry and hydrazone ligation under catalyst-free conditions. We applied the highly efficient hydrazone ligation to couple 2-hydrozinopyridine (2-HP) to aldehyde-functionalized QDs, which produces a stable hydrazone chromophore with a well-defined optical signature. This unique optical feature has enabled us to extract a measure for the ligand density on the QDs for a few distinct sizes and for different ligand architectures, namely mono-LA-PEG and bis(LA)-PEG. We found that the foot-print-area per ligand was unaffected by the nanocrystal size but strongly depended on the ligand coordination number. Additionally, we showed that when the two bio-orthogonal functionalities (aldehyde and azide) are combined on the same QD platform, the nanocrystal can be specifically reacted with two distinct targets and with great specificity. This design yields QD platforms with distinct chemoselectivities that are greatly promising for use as carriers for in vivo imaging and delivery.
- Zhan, Naiqian,Palui, Goutam,Merkl, Jan-Philip,Mattoussi, Hedi
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- Clicking porphyrins to magnetic nanoparticles for photodynamic therapy
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A method for the preparation of superparamagnetic iron oxide nanoparticle-porphyrin (SPION-TPP) conjugates through click chemistry, which can be used as novel theranostic nanoagents for photodynamic therapy is developed. The synthesis, characterisation, and evaluation of the photocytotoxicity profiles of the nanoconjugates prepared is reported. Upon light irradiation, SPION-TPP nanoconstructs promote a photodynamic effect in vitro in murine amelanotic melanoma B78-H1 cells, with IC50 values in the region of 800 nm, similarly to unbound TPP, whereas they remain non-cytotoxic in the dark. However, these nanoconstructs show poor cellular uptake, which influences a linear dose-response effect. Therefore, the improvement of delivery to cells has also been studied by conjugating a well-known cell-penetrating peptide (TAT peptide) to the SPION-TPP nanoparticles. The new nanoconstructs show lower IC50 values (in the region of 500 nm) and a clear dose-response effect. Our results suggest that TAT-conjugated SPION-TPP nanoparticles are efficient nanodevices both for tracking drugs by means of magnetic resonance imaging (MRI)-based techniques and for treating cancer cells through photodynamic therapy, thus functioning as promising theranostic nanoagents.
- Thandu, Merlyn,Rapozzi, Valentina,Xodo, Luigi,Albericio, Fernando,Comuzzi, Clara,Cavalli, Silvia
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- Proline-modified DNA as catalyst of the aldol reaction
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(Chemical Equation Presented) Unbound reactant: Proline-modified DNA acts as catalyst of the intramolecular aldol reaction between a complementary aldehyde and free non-tethered ketones (see scheme). The results of these studies extend the methodological repertoire of DNA-templated reactions.
- Tang, Zhuo,Marx, Andreas
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- Efficient γ-amino-proline-derived cell penetrating peptide-superparamagnetic iron oxide nanoparticle conjugates via aniline-catalyzed oxime chemistry as bimodal imaging nanoagents
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Aniline-catalyzed oxime chemistry was employed to conjugate a γ-amino-proline-derived cell penetrating peptide to superparamagnetic iron oxide nanoparticles (SPIONs). Internalization of the novel nanoconjugate into HeLa cells was found to be remarkably higher compared to the analogous TAT-SPION conjugate.
- Cavalli, Silvia,Carbajo, Daniel,Acosta, Milena,Lope-Piedrafita,Candiota, Ana Paula,Arus, Carles,Royo, Miriam,Albericio, Fernando
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- Co-delivery of Doxorubicin and Interferon-γ by Thermosensitive Nanoparticles for Cancer Immunochemotherapy
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A dual-sensitive nanoparticle delivery system was constructed by incorporating an acid sensitive hydrazone linker into thermosensitive nanoparticles (TSNs) for co-encapsulating doxorubicin (DOX) and interferon γ (IFNγ) and to realize the co-delivery of chemotherapy and immunotherapy agents against melanoma. DOX, a chemotherapeutic drug, was conjugated to TSNs by a pH-sensitive chemical bond, and IFNγ, a potent immune-modulator, was absorbed into TSNs through the thermosensitivity and electrostatics of nanoparticles. Consequently, the dual sensitive drug-loaded TSN delivery systems were successfully built and showed an obvious core-shell structure, good encapsulation efficiency of drugs, sustained and sensitive drug release, prolonged circulation time, as well as excellent synergistic antitumor efficiency against B16F10 tumor bearing mice. Moreover, the combinational antitumor immune responses of hydrazone bearing DOX/IFNγ-TSN (hyd) were strengthened by activating Th1-type CD4+ T cells, cytotoxic T lymphocytes, and natural killer cells, downregulating the expression levels of immunosuppressive cytokines, such as IL10 and TGFβ, and upregulating the secretion of IL2 and TNFα. Taken together, the multifunctional TSNs system provides a promising strategy for multiple drugs co-delivery with distinct properties.
- Yin, Yijia,Hu, Qian,Xu, Chenfeng,Qiao, Qi,Qin, Xianya,Song, Qingle,Peng, Yang,Zhao, Yongdan,Zhang, Zhiping
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- Radical Decarboxylative Carbometalation of Benzoic Acids: A Solution to Aromatic Decarboxylative Fluorination
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Abundant aromatic carboxylic acids exist in great structural diversity from nature and synthesis. To date, the synthetically valuable decarboxylative functionalization of benzoic acids is realized mainly by transition-metal-catalyzed decarboxylative cross couplings. However, the high activation barrier for thermal decarboxylative carbometalation that often requires 140 °C reaction temperature limits both the substrate scope as well as the scope of suitable reactions that can sustain such conditions. Numerous reactions, for example, decarboxylative fluorination that is well developed for aliphatic carboxylic acids, are out of reach for the aromatic counterparts with current reaction chemistry. Here, we report a conceptually different approach through a low-barrier photoinduced ligand to metal charge transfer (LMCT)-enabled radical decarboxylative carbometalation strategy, which generates a putative high-valent arylcopper(III) complex, from which versatile facile reductive eliminations can occur. We demonstrate the suitability of our new approach to address previously unrealized general decarboxylative fluorination of benzoic acids.
- Xu, Peng,López-Rojas, Priscila,Ritter, Tobias
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supporting information
p. 5349 - 5354
(2021/05/05)
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- A METHOD FOR LABELING OF ALDEHYDE CONTAINING TARGET MOLECULES
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The present invention relates to a method for binding to a target molecule comprising an aldehyde a compound derived from N- (2-aminoethyl)pyrrole, which compound also comprises a moiety of interest, to compounds (conjugates) obtained by this method, comprising both the target molecule and the moiety of interest and to novel substances derived from N-(2-aminoethyl)pyrrole.
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(2018/11/10)
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- Synthesis and optical properties of BODIPY with active group on meso-position
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Background: In this work a few approaches for the synthesis of 4,4-difluoro-8-(4′-carboxyphenyl)-4-bora-3a,4a-diaza-s-indacene are considered. The process of obtaining this boron fluoride complex involves the following stages: introduction of the protective group (methoxy-, 1′-pyrrolidine-2,5-dion-, trichloroethoxy-) on the carboxy-group of 4-formylbenzoic acid, condensation with pyrrole, removal of protection, oxidation, and complexation proper. A method of direct condensation of pyrrole with the 4-formylbenzoic acid in the presence of a catalytic amount of 0.1 M HCl was proposed to achieve a high yield of the target product. All synthesized compounds were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectrometry and elemental analysis. Values of fluorescence quantum yield and Stokes shift were calculated for boron fluoride complexes of dipyrrolylmethenes. Methods: IR spectra were recorded on a Bruker Vertex 80V device in the regions of 7500-350 cm-1 from pellets with KBr. The NMR spectral studies on the nuclei 1H and 13C were performed on a Bruker Avance-500 instrument (500.13 MHz) in CDCl3, the internal standard was TMS. Elemental analyses of crystalline compounds were carried out on a FlashEA 1112 analyzer. Mass spectra were registered on a JMS-700 JEOL (FAB) and JMS-100GCV JEOL (EI) mass-spectrometers. UV/V is spectra and fluorescence spectra were recorded on a spectrofluorimeter CM 2203 (SOLAR) in CH2Cl2, with square quartz cavity being 10 mm thick. The fluorescence quantum yield was determined by formula utilizing fluorescein in 0.1 M NaOH as a standard (ΦS=0.85). Results: All the synthesized compounds have a smaller fluorescence quantum yield as compared to the standard and most BODIPY, in which the meso-position does not contain aryl and the other mobile substituents. The decrease in the quantum yield of meso-aryl-substituted BODIPY due to the rotation of the meso-substituent relative BODIPY core leads to non-radiative transitions. Fluorophores are stable upon illumination (no changes in the electronic absorption and fluorescence spectra are observed when they are affected by a continuous light). The Stokes shift is from 30 to 52 nm. Conclusion: A few approaches to synthesize 4,4-difluoro-8-(4′-carboxyphenyl)-4-bora-3a,4a-diaza-s-indacene are considered. The process of obtaining this boron fluoride complex involves the following stages: introduction of the protective group (methoxy-, 1′-pyrrolidine-2,5-dion-, trichloroethoxy-) on the carboxy-group of 4-formylbenzoic acid, condensation with pyrrole, removal of protection, oxidation, and complexation proper. A method of direct condensation of pyrrole with the 4-formylbenzoic acid in the presence of a catalytic amount of 0.1 M HCl was proposed to achieve a high yield of the target product. Values of fluorescence quantum yield and Stokes shift were calculated for boron fluoride complexes of dipyrrolylmethenes.
- Matvey, Gruzdev,Ulyana, Chervonova,Natalia, Bumagina,Arkadiy, Kolker
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p. 718 - 725
(2017/02/05)
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- SITE SELECTIVE CONJUGATION OF AN OLIGONUCLEOTIDE CONJUGATE OR A SMALL MOLECULE TO A METAL BINDING PROTEIN
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The present invention relates to methods for site selective conjugation of an oligonucleotide conjugate to a metal binding protein comprising a metal binding site and for site selective conjugation of a small molecule conjugation compound (SMCoC) to an antibody comprising a metal binding site, metal binding protein conjugates obtainable by said methods, and uses of said metal binding protein conjugates.
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Page/Page column 59
(2016/01/25)
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- Factor VIII Molecules With Reduced VWF Binding
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The present invention relates to a recombinant Factor VIII molecule, wherein said molecule has reduced vWF binding capacity, and wherein said molecule is covalently conjugated with at least one side group.
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Paragraph 0177 - 0180
(2016/03/04)
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- A DNA-templated synthesis of encoded small molecules by DNA self-assembly
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We report a novel method for the synthesis of DNA-encoded libraries without the need for discrete DNA template. Reactant DNAs self-assemble to enable chemical reactions and photo-cleavage transfers the product to the DNA terminus, making it suitable for the subsequent affinity-based selection and hit deconvolution. This journal is the Partner Organisations 2014.
- Cao, Cheng,Zhao, Peng,Li, Ze,Chen, Zitian,Huang, Yanyi,Bai, Yu,Li, Xiaoyu
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supporting information
p. 10997 - 10999
(2014/11/07)
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- Cleavable trifunctional biotin reagents for protein labelling, capture and release
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Trifunctional biotin reagents incorporating cleavable linkers are evaluated for their usage in protein enrichment. A linker based on the Dde protecting group leads to efficient release of protein targets under mild conditions. It additionally contains a masked trypsin cleavage site, which eliminates the majority of the tag during tryptic digestion.
- Yang, Yinliang,Verhelst, Steven H. L.
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supporting information
p. 5366 - 5368
(2013/07/11)
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- TARGETED DELIVERY OF FACTOR VIII PROTEINS TO PLATELETS
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The invention described herein relates to novel molecules and polypeptides comprising at least one amino acid sequence having significant identity with (homology to) human Factor VIII or biologically active portion(s) thereof, related molecules (such as n
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- Reaction discovery by using a sandwich immunoassay
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Mmm, a reaction sandwich Using an immunoassay-based technique able to monitor any kind of cross-coupling reaction, a systematic and rapid evaluation of a large panel of random reactions was carried out. This approach led to the discovery of two new copper-promoted reactions: a desulfurization reaction of thioureas leading to isoureas and a cyclization reaction leading to thiazole derivatives from alkynes and N-hydroxy thioureas. Copyright
- Quinton, Julia,Kolodych, Sergii,Chaumonet, Manon,Bevilacqua, Valentina,Nevers, Marie-Claire,Volland, Herve,Gabillet, Sandra,Thuery, Pierre,Creminon, Christophe,Taran, Frederic
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supporting information; experimental part
p. 6144 - 6148
(2012/07/17)
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- A fluorescently labeled dendronized polymer-enzyme conjugate carrying multiple copies of two different types of active enzymes
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A hybrid structure of a synthetic dendronized polymer, two different types of enzymes (superoxide dismutase and horseradish peroxidase), and a fluorescent dye (fluorescein) was synthesized. Thereby, a single polymer chain carried multiple copies of the tw
- Grotzky, Andrea,Nauser, Thomas,Erdogan, Huriye,Schlueter, A. Dieter,Walde, Peter
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supporting information; experimental part
p. 11392 - 11395
(2012/08/29)
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- Modification of Factor VIII
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A Factor VIII derivative of formula (I): wherein: B represents C2 to C10 alkylene; m represents 0 or an integer from 1 to 19, n represents an integer from 1 to 20, and the sum of m and n is from 1 to 20; P represents a mono or polyradical of Factor VIII obtained by removing m+n carbamoyl groups from the side chains of glutamine residues in Factor VIII; and M represents a moiety (M1) that increases the plasma half-life of the Factor VIII derivative or a reporter moiety (M2); or a pharmaceutically acceptable salt thereof.
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- Construction of a FRET-based ratiometric fluorescent thiol probe
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We have rationally constructed a novel FRET-based ratiometric thiol probe suitable for ratiometric imaging in living cells based on the native chemical ligation reaction.
- Long, Lingliang,Lin, Weiying,Chen, Bingbing,Gao, Wensha,Yuan, Lin
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supporting information; scheme or table
p. 893 - 895
(2011/02/25)
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- A universal and ready-to-use heterotrifunctional cross-linking reagent for facile synthetic access to sophisticated bioconjugates
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We describe for the first time, the synthesis and some bioconjugation applications of an original heterotrifunctional cross-linking reagent (also named tripod) bearing three different bioorthogonal functional groups which are fully compatible amongst themselves. Contrary to the first generation tripod recently reported by us (Org. Biomol. Chem., 2008, 6, 3065), the use of an azido group instead of the nucleophile-sensitive active carbamate moiety enables us to reach the targeted chemical orthogonality without the use of temporary aminooxy- and thiol protecting groups. Thus, the preparation of sophisticated bioconjugates through the sequential derivatisation of the tripod by means of copper-mediated 1,3-dipolar cycloaddition, oxime ligation and aqueous compatible mild thiol-alkylation reactions, is significantly simpler and more convenient. The chemoselective bioconjugation protocols were optimised through the preparation of FRET cassettes based on cyanine and/or xanthene fluorescent dye pairs and subsequent anchoring to fragile biomolecules. The applicability of this universal cross-linking reagent was also illustrated by the preparation of biochips suitable for aflatoxin B1 detection through the SPIT-FRI method.
- Clave, Guillaume,Volland, Herve,Flaender, Melanie,Gasparutto, Didier,Romieu, Anthony,Renard, Pierre-Yves
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experimental part
p. 4329 - 4345
(2010/11/18)
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- Compositions and methods for treating cancer
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The invention features compositions and methods for treating or alleviating a symptom of cancer. The compositions and methods of the invention direct supra-lethal doses of radiation, called Hot-Spots, to virtually all cancer cell types.
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(2008/06/13)
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- Kinetic model studies on the chemical ligation of oligonucleotides via hydrazone formation
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We report on the suitability of hydrazone formation for activator-free ligation of oligonucleotides. 5′-Acyl hydrazides were synthesized using a previously described phosphoramidite modifier, whereas 3′-hydrazides resulted from a hydrazinolysis of an ester group serving as a linker to the solid support. Aromatic aldehydes could be directly introduced on the 5′-terminus via the respective phosphoramidates. Aliphatic aldehydes were generated by periodate cleavage of the corresponding 3′- and 5′-modified diol precursors. Ligation of a 3′-hydrazide-modified oligonucleotide with oligonucleotides bearing an aromatic aldehyde in 5′-position showed a fast reaction kinetics (k1 about 10 -1) and irreversible hydrazone formation. The ligation of a 5′-hydrazide-modified oligonucleotide and a 3′-ribobisaldehyde appeared to proceed reversibly at the beginning, but became irreversible with increasing reaction time. Hydrazide-modified oligonucleotides were found to be somewhat unstable in aqueous solutions.
- Achilles,Kiedrowski
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p. 1229 - 1233
(2007/10/03)
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