发布求助
文献互助 智能选刊 最新文献

Helvetica Chimica Acta最新文献

筛选
英文 中文
ETHos – A Swiss-Made Open-Source Modular Photoreactor for Laboratory-Scale Photochemical Reactions ETHos -瑞士制造的开源模块化光反应器，用于实验室规模的光化学反应
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-12-06 DOI: 10.1002/hlca.202400154
Jonas W. Rackl, Alexander F. Müller, Christoph Bärtschi, Helma Wennemers
{"title":"ETHos – A Swiss-Made Open-Source Modular Photoreactor for Laboratory-Scale Photochemical Reactions","authors":"Jonas W. Rackl,&nbsp;Alexander F. Müller,&nbsp;Christoph Bärtschi,&nbsp;Helma Wennemers","doi":"10.1002/hlca.202400154","DOIUrl":"https://doi.org/10.1002/hlca.202400154","url":null,"abstract":"<p>The emergence of photoredox chemistry has enabled the development of previously inaccessible synthetic transformations. Despite the popularity of photoredox chemistry, commercial photoreactors remain expensive. As a result, most academic research groups resort to self-built, not easily replicable reactor designs, jeopardizing the reproducibility and accessibility of photochemical research. To address these issues, this work introduces an easily replicable and modular open-source photoreactor optimized for lab-scale photochemical synthesis. The reactor is operationally simple, operates consistently and reproducibly, and is inexpensive to manufacture. Our design integrates active temperature regulation, an exchangeable vial rack, and customizable light sources into a hybrid structure of machined aluminum, 3D-printed parts, and commercially available components. The open-source reactor with detailed 3D CAD files on GitHub is designed to make research in the field of photochemistry more accessible and reproducible.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 12","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142860402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Diamonds in Chemical Space: The Synthesis of Brexazine 化学空间中的钻石：布雷赛嗪的合成
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-12-05 DOI: 10.1002/hlca.202400175
Leon Rebhan, Ye Buehler, Jean-Louis Reymond
{"title":"Diamonds in Chemical Space: The Synthesis of Brexazine","authors":"Leon Rebhan,&nbsp;Ye Buehler,&nbsp;Jean-Louis Reymond","doi":"10.1002/hlca.202400175","DOIUrl":"https://doi.org/10.1002/hlca.202400175","url":null,"abstract":"<p>Here we searched chemical space for small and novel diamond-like, 3D-shaped building blocks, which are very rare but highly valuable for medicinal chemistry because they can increase the natural product likeness of drug molecules and improve their selectivity, water solubility and metabolism. We explored the Generated DataBases (GDBs), which list all possible organic molecules up to a defined size, identified 162 norbornane containing ring systems related to the known trinorbornane, and took inspiration from its simpler substructure brexane to design brexazine as a new chiral and 3D-shaped piperazine analog. The synthesis of brexazine was realized in 11 steps and 11.5 % overall yield from a commercially available norbornene building block. These experiments illustrate the value of exploring chemical space from first principles to design new building blocks for drug discovery.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"108 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143112008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Red-Shifted Bioluminescence Using Substrate-Fluorophore Conjugates 利用底物-荧光基团共轭物的红移生物发光
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-12-05 DOI: 10.1002/hlca.202400156
Clément Narbonne Zuccarelli, José Laxio-Arenas, Francesco Russo, Nicolas Winssinger
{"title":"Red-Shifted Bioluminescence Using Substrate-Fluorophore Conjugates","authors":"Clément Narbonne Zuccarelli,&nbsp;José Laxio-Arenas,&nbsp;Francesco Russo,&nbsp;Nicolas Winssinger","doi":"10.1002/hlca.202400156","DOIUrl":"https://doi.org/10.1002/hlca.202400156","url":null,"abstract":"<p>NanoLuc (NLuc) is one of the brightest luciferases and has been used in numerous reporter assays and sensor designs. However, its blue light emission (460 nm) is suboptimal for deep tissue imaging or some diagnostic application, and red shifting its emission is desirable. Here, we report the design and synthesis of novel furimazine and coelenterazine analogs conjugated with fluorophores to achieve red-shifted bioluminescence with NLuc and closely related H-Luc via a bioluminescence resonance energy transfer (BRET). Structural insights into NLuc-substrate interactions informed the functionalization of substrates. We report the synthesis of novel substrate-fluorophore conjugates. We show that red-shifted emission was achieved with high BRET ratios. The conjugates are less bright than the parent substrates, but our study highlights the importance of linker length and flexibility for optimizing bioluminescence emission reaching wavelength beyond 600 nm.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"108 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143112009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Interactions and Click Functionalization of a Poly(Thiophenyl-Tetrazine-Co-Fluorene) Conjugated Polymer with Single-Walled Carbon Nanotubes 聚噻吩-四氮-共芴共轭聚合物与单壁碳纳米管的相互作用和点击功能化
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-12-04 DOI: 10.1002/hlca.202400146
Shagana Kukendran, Sara Salimi, Alex Adronov
{"title":"Interactions and Click Functionalization of a Poly(Thiophenyl-Tetrazine-Co-Fluorene) Conjugated Polymer with Single-Walled Carbon Nanotubes","authors":"Shagana Kukendran,&nbsp;Sara Salimi,&nbsp;Alex Adronov","doi":"10.1002/hlca.202400146","DOIUrl":"https://doi.org/10.1002/hlca.202400146","url":null,"abstract":"<p>A highly soluble thiophene-based poly(tetrazine) polymer was prepared that can undergo inverse-electron-demand Diels-Alder (IEDDA) click reactions efficiently with different types of <i>trans</i>-cyclooctene (TCO) derivatives resulting in post-polymerization functionalization. The resulting pyridazines post-oxidation exhibited strong interactions with single-walled carbon nanotubes (SWNTs) and showed selectivity toward metallic SWNTs. The resulting dispersions were used to prepare thin films, whose sheet resistivity was measured. It was found that α-amino-ω-methoxy triethylene glycol (TEG) functionalized pyridazine dispersion film resulted in a lower sheet resistance by several orders of magnitude compared to the non-clicked tetrazine dispersion indicating better conductivity post-IEDDA. Furthermore, modification of the polymer backbone while bound to the SWNT was performed successfully, preserving the properties of the nanotubes.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"108 2","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400146","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Photoinduced Energy Transfer via an Atropisomeric Molecular Bridge 通过atrosomomer分子桥的光诱导能量转移
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-12-04 DOI: 10.1002/hlca.202400163
Dominik Lotter, Annika Huber, Joël Wellauer, Oliver S. Wenger, Christof Sparr
{"title":"Photoinduced Energy Transfer via an Atropisomeric Molecular Bridge","authors":"Dominik Lotter,&nbsp;Annika Huber,&nbsp;Joël Wellauer,&nbsp;Oliver S. Wenger,&nbsp;Christof Sparr","doi":"10.1002/hlca.202400163","DOIUrl":"https://doi.org/10.1002/hlca.202400163","url":null,"abstract":"<p>Atropisomeric scaffolds offer the possibility to predictably position donor and acceptor groups in specific spatial relationships. Herein, a configurationally stable 1,2’-binaphthyl linkage was employed to place a ruthenium(II) tris-(2,2’-bipyridine) complex in proximity to an anthracene moiety to explore how photoinduced triplet-triplet energy transfer can proceed across this type of molecular bridge. An efficient synthesis provided the ruthenium(II)-anthracene dyad with high yields, which allowed to determine characteristic features for the intramolecular energy transfer.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"108 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400163","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143111742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Stability of Shielded Pentacenes under Ambient Conditions 环境条件下屏蔽五苯的稳定性
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-11-28 DOI: 10.1002/hlca.202400161
Philipp Ludwig, Paul Kilian, Patrick Mayerhofer, Nikolai Hippchen, Frank Rominger, Jan Freudenberg, Uwe H. F. Bunz
{"title":"Stability of Shielded Pentacenes under Ambient Conditions","authors":"Philipp Ludwig,&nbsp;Paul Kilian,&nbsp;Patrick Mayerhofer,&nbsp;Nikolai Hippchen,&nbsp;Frank Rominger,&nbsp;Jan Freudenberg,&nbsp;Uwe H. F. Bunz","doi":"10.1002/hlca.202400161","DOIUrl":"https://doi.org/10.1002/hlca.202400161","url":null,"abstract":"<p>The stabilization of pentacene through variation of substituents serves as a test bed to access stable organic semiconductors, transferable to the larger soluble acenes and azaacenes. Pentacene is stable enough for derivatization via wet-chemistry but sufficiently labile to test its (induced) (photo)decomposition. In this article, we describe the synthesis of shielded pentacenes, either via covalent jacketing with ester macrocycles or via steric shielding with biphenylyl substituents, together with attempts to access a bis(<i>ortho</i>-quaterphenylyl) substituted Geländer pentacene. The photostability of the pentacenes is assessed under ambient conditions (air, light) to simulate handling under typical laboratory conditions and put into perspective with reference compounds, such as TIPS-ethynylated, ether-jacketed or our previously reported Geländer pentacenes.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"108 4","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400161","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Radical C4−H Arylation of 1,4-Dihydropyridines with Cyanoarenes 1,4-二氢吡啶与氰芳烃的自由基C4−H芳基化反应
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-11-20 DOI: 10.1002/hlca.202400162
Huaixuan Guo, Shiqin Qiu, Peng Xu
{"title":"Radical C4−H Arylation of 1,4-Dihydropyridines with Cyanoarenes","authors":"Huaixuan Guo,&nbsp;Shiqin Qiu,&nbsp;Peng Xu","doi":"10.1002/hlca.202400162","DOIUrl":"https://doi.org/10.1002/hlca.202400162","url":null,"abstract":"<p>4-Aryl-1,4-dihydropyridines are prevalent pharmacophores and versatile building blocks in medicinal and synthetic chemistry. Herein, we demonstrated a mechanistically distinct radical-radical cross-coupling approach to 4-aryl-1,4-dihydropyridines, via direct C4−H arylation of 1,4-dihydropyridines with readily available cyanoarenes. This mild protocol is initiated by the direct photoexcitation of 1,4-dihydropyridines, eliminating the need for expensive photocatalysts and enabling operation under ambient air conditions.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 12","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142861747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Cover Picture: (Helv. Chim. Acta 11/2024) 封面图片：（Helv.）
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-11-16 DOI: 10.1002/hlca.202471101
{"title":"Cover Picture: (Helv. Chim. Acta 11/2024)","authors":"","doi":"10.1002/hlca.202471101","DOIUrl":"https://doi.org/10.1002/hlca.202471101","url":null,"abstract":"<p>\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 11","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202471101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The pKa of Water and the Fundamental Laws Describing Solution Equilibria: An Appeal for a Consistent Thermodynamic Pedagogy 水的 pKa 和描述溶液平衡的基本规律：呼吁采用一致的热力学教学法
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-11-13 DOI: 10.1002/hlca.202400103
Thomas L. Neils, Stephanie Schaertel, Todd P. Silverstein
{"title":"The pKa of Water and the Fundamental Laws Describing Solution Equilibria: An Appeal for a Consistent Thermodynamic Pedagogy","authors":"Thomas L. Neils,&nbsp;Stephanie Schaertel,&nbsp;Todd P. Silverstein","doi":"10.1002/hlca.202400103","DOIUrl":"https://doi.org/10.1002/hlca.202400103","url":null,"abstract":"<p>A recurring misconception in some textbooks and research papers has led to an abandonment of fundamental physical laws when describing a subset of acid-base equilibria, especially regarding the role of the solvent. In the specific case of the autoprotolysis of water, experiments and theoretical calculations prove that the <i>K</i><sub>w</sub> of water at 25 °C, 1.00×10<sup>−14</sup>, is identical to its acid ionization constant, <i>K</i><sub>a</sub>. Nevertheless, several articles have been published erroneously purporting to give theoretical proof that the <i>K</i><sub>a</sub> of water is 10<sup>−15.743</sup> (1.81×10<sup>−16</sup>) and that the <i>K</i><sub>a</sub> of the aqueous proton (hydronium ion) is 55.3 rather than 1.00. Here we argue that using the incorrect numbers has pedagogical implications beyond those of a simple error. Arguments for the incorrect <i>K<sub>a</sub></i> and p<i>K<sub>a</sub></i> values require a misapplication of Henry's law and violate long-standing methods that use Raoult's law and the conservation of matter to describe the behavior of solutions. As a result, chemistry students may be asked to accept one set of physical principles in one course and another set in another course. Here we argue for adherence to fundamental physical laws governing solution equilibria as applied to the autoprotolysis of water and all aqueous acid base equilibria.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 11","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Suppressing Inversion of a Chiral Polycyclic Aromatic Aza Monkey Saddle by Molecular Editing 通过分子编辑抑制手性多环芳香族氮杂环猴鞍的反转
IF 1.5 4区 化学
Helvetica Chimica Acta Pub Date : 2024-11-04 DOI: 10.1002/hlca.202400158
Tobias Kirschbaum, Simone Felicia Ebel, Frank Rominger, Michael Mastalerz
{"title":"Suppressing Inversion of a Chiral Polycyclic Aromatic Aza Monkey Saddle by Molecular Editing","authors":"Tobias Kirschbaum,&nbsp;Simone Felicia Ebel,&nbsp;Frank Rominger,&nbsp;Michael Mastalerz","doi":"10.1002/hlca.202400158","DOIUrl":"https://doi.org/10.1002/hlca.202400158","url":null,"abstract":"<p>Chiral polycyclic aromatic hydrocarbons with monkey saddle topology are a fascinating class of negatively curved compounds. To make the monkey-saddles valuable building blocks for chirality-assisted synthesis (CAS) approaches, the inversion barriers between the two possible enantiomers need to be high enough to prevent interconversion under CAS conditions. By molecular editing, aza monkey saddles were converted to the corresponding chromene monkey saddles that are configurationally stable even at temperatures of 220 °C over a period of 47 days. Their structures were studied by single X-ray diffraction and enantiomers were separated to study the chiroptical properties. Furthermore, mechanistic assumptions of the formation of the chromene monkey saddles by DFT calculations are discussed.</p>","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 12","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400158","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142860171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信