Polydiacetylene Micelles in Nanomedicine and Beyond
Conclusion [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - February 9, 2024 Category: Chemistry Authors: Gravel, Edmond Demeese, C éline Doris, Eric Tags: account Source Type: research
A Redox Tale of Two Phosphine Oxides (and a Terthiophene)
Synlett DOI: 10.1055/s-0042-1751551 Despite the appeal of organic redox systems as next-generation energy-storage media, achieving high cell voltages with electrolytes based on main-group elements typically comes at the cost of reduced long-term stabilities. In this Synpacts article, we summarize our recent finding that the introduction of phosphine oxide functionalities can unlock the ability of terthiophenes to serve as robust two-electron acceptors at extreme potentials. These investigations uncovered a fundamentally new class of multielectron redox systems, capable of expanding the cell potential range achievable with ...
Source: Synlett - February 7, 2024 Category: Chemistry Authors: K äch, Daniel Bezdek, M áté J. Tags: synpacts Source Type: research
Multicomponent Reaction-Based Heteroannulations: A Direct Access to Fused Tetrazolo Piperazinones and 1,4-Diazepanones
Synlett DOI: 10.1055/a-2239-6897 By exploiting the chemistry of bifunctional isocyanides, straightforward, rapid, and scalable Ugi-tetrazole-based multicomponent reaction heteroannulations were developed. Our synthetic approach provides a series of diverse fused tetrazolo piperazinones and 1,4-diazepanones in just one step. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - February 7, 2024 Category: Chemistry Authors: Fotopoulou, Eirini Vasilakis, Alexandros Neochoritis, Constantinos G. Tags: letter Source Type: research
Synthesis of a New Heterocyclic System: Pyrimidine Structural Analogues of Natural Integrastatins A, B
Synlett DOI: 10.1055/a-2239-6657 In this paper for the first time, we report a simple one-step synthesis of 5-methyl-11,12-dihydro-5H-5,11-epoxybenzo[7,8]oxocino[4,3-d]pyrimidine derivatives by acid-catalyzed cyclization reaction of various 4-methyl-5-acetyl pyrimidine derivatives with salicylic aldehyde. It was shown that 2-substituted 4-methyl-5-acetylpyrimidines successfully react to form a cyclization product. At the same time, 4-methyl-5-acetylpyrimidines with a substituent in the 6th position do not enter into the cyclization reaction. This may be caused by the negative effect of substituents in the 6th position, whi...
Source: Synlett - February 7, 2024 Category: Chemistry Authors: Chikunov, Semyon Y. Pustolaikina, Irina A. Gatilov, Yuriy V. Kulakov, Ivan V. Tags: letter Source Type: research
Directing Hydrogen Isotope Exchange with Aryl Carboxylic Acids
Synlett DOI: 10.1055/a-2239-6965 A highly effective and selective ortho-directed hydrogen isotope exchange process for aryl carboxylic acids has been achieved by using an iridium(I) N-heterocyclic carbene/phosphine complex under mild and neutral conditions. Good levels of deuterium incorporation have been delivered across a wide array of examples, including a number of biologically active drug compounds. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - February 5, 2024 Category: Chemistry Authors: Mudd, Richard J. Reid, Marc Paterson, Laura C. Atzrodt, Jens Derdau, Volker Kerr, William J. Tags: letter Source Type: research
Modular Synthesis of Methyl-Substituted Novel Psoralen N-Hydroxysuccinimide Esters and Evaluation of DNA Photocrosslinking Properties of the Corresponding Triplex-Forming Oligonucleotide Conjugates
Synlett DOI: 10.1055/a-2229-7441 Psoralen-conjugated triplex-forming oligonucleotides (Ps-TFOs) have been used to induce DNA mutations or to suppress gene expression through the formation of crosslinked products with DNA in a sequence-specific manner. Psoralen can crosslink with DNA at its furan-ring and/or pyrone-ring side, yielding either a monoadduct or diadduct (interstrand crosslinking) product. The differences in the crosslinked structures of Ps-TFOs with the target DNAs are closely related to the changes in the biological outcomes induced by the Ps-TFOs. However, only a few reports have discussed the photocrosslinki...
Source: Synlett - February 5, 2024 Category: Chemistry Authors: Mikame, Yu Maekawa, Nagisa Kimura, Soichiro Nakao, Juki Yamayoshi, Asako Tags: letter Source Type: research
Modular Synthesis of 4-Acylquinolines via Cycloaddition of 1,3-Enynes and Nitrosoarenes
Synlett DOI: 10.1055/a-2229-1963 Herein, we disclose a FeBr2-promoted cycloaddition of readily available 1,3-enynes and nitrosoarenes, providing a promising platform for the synthesis of privileged 4-acylquinoline scaffolds. This simple, one-pot process is characterized by high atom-economy, broad substrate-scope, and excellent functional-group tolerance. A possible reaction mechanism was proposed, involving processes such as [4+2] cycloaddition, ring opening, aromatization, and dehydroaromatization. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents |...
Source: Synlett - February 5, 2024 Category: Chemistry Authors: Li, Xiao Diao, Chenxin Kong, Wangqing Tags: letter Source Type: research
Catalytically Competent Fluorinated Barnase Variants
Synlett DOI: 10.1055/a-2219-6830 Proteins play critical roles in all living organisms, and their properties and functions result directly from their primary sequences. Fluorine, though seldom found in natural organic compounds, has been shown to impart desirable properties to small molecules and proteins alike. However, studies on the impact of this element in enzyme activity and protein–protein interaction are largely absent from the literature. Here we present a microwave-assisted SPPS method for the total synthesis of site-specifically fluorinated barnase variants, as well as characterization of their folding and acti...
Source: Synlett - February 5, 2024 Category: Chemistry Authors: Langhans, Alexander Krummhaar, Michael Roth, Christian Koksch, Beate Tags: letter Source Type: research
Acidic Hydrogen-Tethered Electron-Deficient Acceptors for Phosphine-Catalyzed Annulations
Conclusions [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - February 5, 2024 Category: Chemistry Authors: Zhou, Leijie Guo, Hongchao Tags: account Source Type: research
Design of Imidazo[1,2-a]pyridine-Based Donor –Acceptor Chromophores through a Multicomponent Approach
Synlett DOI: 10.1055/a-2236-8949 A series of donor-acceptor chromophores was synthesized bearing a 3-aminoimidazo[1,2-a]pyridine donor motive. Through DFT calculations, different combinations of the ImPy donor motive and different electron acceptors were assessed. In combination with an anthraquinone acceptor, the calculated ΔE
ST values were in range to suggest that these compounds would emit via thermally activated delayed fluorescence. Based on these findings, a series of ImPy-Aq emitters with different geometries and substitution patterns was synthesized through GBB-3CR and Suzuki coupling reactions. Accordin...
Source: Synlett - February 1, 2024 Category: Chemistry Authors: Stahlberger, Mareen Mergel, Milada dos Santos, John Marques Matulaitis, Tomas Nieger, Martin Zysman-Colman, Eli Br äse, Stefan Tags: letter Source Type: research
Solvent-Free Synthesis of α-Cyanophosphonates from β-Nitrostyrenes by Using a Deep-Eutectic Solvent Catalyst
Synlett DOI: 10.1055/a-2239-6819 α-Cyanophosphonates, which are useful reagents for the Horner–Wittig reaction, were synthesized under solvent-free conditions by using a choline chloride–zinc chloride deep-eutectic solvent (DES) as a catalyst. This is only the second report on the synthesis of these compounds. In the previous report, diethyl trimethylsilyl phosphite was used as a reagent and TiCl4 as a catalyst, whereas in this study, both the reagent (triphenylphosphine) and the catalyst (choline chloride–zinc chloride DES) are cheaper, more readily available, and less harmful than those used in the previous work. ...
Source: Synlett - January 31, 2024 Category: Chemistry Authors: Shamsaddinimotlagh, Sima Ranjbari, Mohammad A. Tavakol, Hossein Shi, Min Tags: letter Source Type: research
Rationalizing the Regioselectivity of Azolation of Benzylic C –H Bonds under Photoredox Catalysis
Synlett DOI: 10.1055/a-2236-1122 A density functional theory (DFT) study was performed to evaluate the reaction mechanism of the C–N bond formation under an integrated hydrogen atom transfer/radical-polar crossover photoredox catalytic cycle. The regioselective activation of a model substrate, including three reactive positions (3° benzylic C–H bond, 2° benzylic C–H bond, and primary C–Cl bond) was addressed to distinguish among the radical C–H activation mechanism and the standard SN2 reaction. We demonstrated that activation of tertiary benzylic C–H bond is the most favored and forms exclusively the experim...
Source: Synlett - January 31, 2024 Category: Chemistry Authors: Sanosa, Nil Montiel-Cervantes, C ésar Rubio-Mu ñoz, Miguel Sampedro, Diego Funes-Ardoiz, Ignacio Tags: letter Source Type: research
Sultines as o-Quinodimethane Precursors in an Oxa-Diels –Alder Reaction: Synthesis of Functionalized Isochromans
Synlett DOI: 10.1055/a-2236-9589 The development of an oxa-Diels–Alder reaction between sultines and carbonyl compounds is reported. o-Quinodimethanes, generated from sultines, undergo a [4+2]-cycloaddition with activated aldehydes or ketones in the presence of Cu(OTf)2 to provide a variety of functionalized isochromans, including spiroisochromans, in up to 99% yield. The developed protocol demonstrates broad functional-group compatibility and tolerates unprotected isatins bearing free NH-functionalities. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of conten...
Source: Synlett - January 31, 2024 Category: Chemistry Authors: Ngamnithiporn, Aurapat Chuentragool, Padon Songthammawat, Poramate Punnita, Supakarn Photong, Kittithuch Ploypradith, Poonsakdi Ruchirawat, Somsak Tags: letter Source Type: research
Palladium-Catalyzed Cycloisomerization of Carbamimidothioates
Synlett DOI: 10.1055/s-0043-1763663 A palladium-catalyzed cycloisomerization of carbamimidothioates with the formation of a quaternary carbon and a sulfide is described. The use of (IPr)Pd(allyl)Cl (CX21), K3PO4, and Me-C(OTBS)=NTBS in refluxing xylenes was optimal, and the methoxycarbonyl group was the most suitable substituent for the nitrogen atom of the carbamimidothioate. Phenyl and alkyl groups can be used as tethers for carbamimidothioates, and alkyl and aryl carbamimidothioates can undergo Pd-catalyzed cycloisomerization in high yields. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticl...
Source: Synlett - January 30, 2024 Category: Chemistry Authors: Kumazawa, Hyu Mizoguchi, Kota Okura, Yoshifumi Nakada, Masahisa Tags: letter Source Type: research
Aromatic Residue Positioning Influences Helical Peptoid Structure in Aqueous Solution
Synlett DOI: 10.1055/a-2238-5394 Water-soluble peptidomimetics, including peptoids, are promising functional surrogates for biologically relevant, amphiphilic, helical peptides. Twenty amphiphilic peptoid hexamers with predicted helical structures were designed, prepared, and studied using circular dichroism (CD) spectroscopy. The site-specific contributions of aromatic and charged residues to the helical structure of peptoid hexamers in aqueous solution was evaluated, revealing that aromatic residue positioning most significantly impacts structure. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyA...
Source: Synlett - January 30, 2024 Category: Chemistry Authors: Javed, Jwwad M. Scukas, Katherine Nguyen, Michelle T. Fuller, Amelia A. Tags: letter Source Type: research
