Helvetica Chimica Acta最新文献_第6页

Diversity of Structures and Bonding in Alkali Metal Ureaphosphanes 碱金属脲膦的结构和键合多样性

IF 1.5 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-28 DOI: 10.1002/hlca.202400077

Michelle H. Crabbe, Alan R. Kennedy, Catherine E. Weetman, Robert E. Mulvey

{"title":"Diversity of Structures and Bonding in Alkali Metal Ureaphosphanes","authors":"Michelle H. Crabbe, Alan R. Kennedy, Catherine E. Weetman, Robert E. Mulvey","doi":"10.1002/hlca.202400077","DOIUrl":"10.1002/hlca.202400077","url":null,"abstract":"While organoelement compounds of lithium, sodium and potassium have been much studied for decades and consequently have found forests of applications, those of the heavier alkali metals, rubidium and caesium would barely manage to fill a tree. However, recently the literature has seen some little growth spurts with these metals, hinting at a possible fertile future in areas such as homogeneous catalysis provided more work is put into their fundamental development. Here we report the synthesis and crystal structures of lithium, rubidium and caesium derivatives of the ureaphosphane Ph2PCH2CH2NHC(=O)NHPh, chosen because it offers O, N, P, and π-coordination sites. Though one may expect such alkali metal compounds to be essentially similar, the caesium complex has novel features where Cs+ engages in a side-on coordination to the C=O bond and in a weak bond to the P centre, both of which are absent in the Rb structure. Less surprisingly, the lithium derivative is tetrameric in contrast to the infinite networks of the rubidium and caesium structures. All alkali metal derivatives were made with deprotonating the ureaphosphane by a suitable base, including the sodium and potassium complexes though these two complexes could not be obtained in a crystalline form.","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 8","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400077","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141191595","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

Cover Picture: (Helv. Chim. Acta 5/2024) 封面图片： (Helv. Chim. Acta 5/2024)

IF 1.8 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-15 DOI: 10.1002/hlca.202470501

引用次数: 0

A Highly Efficient Click Linker for Enrichment of Alkyne-Tagged Proteins in Living Cells 用于活细胞中烯炔标记蛋白质富集的高效点击链接器

IF 1.8 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-10 DOI: 10.1002/hlca.202400031

Guoting Qin, Shara Duong, Yunxin Fu, Chengzhi Cai

引用次数: 0

Fluorescent Membrane Probes Obey the Israelachvili Rules 遵守伊斯拉赫维利规则的荧光膜探针

IF 1.5 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-09 DOI: 10.1002/hlca.202400062

Felix Bayard, Stefan Matile

{"title":"Fluorescent Membrane Probes Obey the Israelachvili Rules","authors":"Felix Bayard, Stefan Matile","doi":"10.1002/hlca.202400062","DOIUrl":"10.1002/hlca.202400062","url":null,"abstract":"When developing fluorescent membrane probes, we naturally tend to focus on the fluorophore itself. In this study, we show that sometimes it can be beneficial to shift attention from the center to the periphery, to maximize multiple interfacing with complex changing environments. Palmitylation for hydrophobic interfacing and glutamate dendrons for hydrophilic interfacing are combined to improve the performance of fluorescent flipper probes. We show that to increase performance in membranes, solubility in water is important, and to increase solubility in water, we increase the hydrophobicity of the flipper probe. These seemingly paradoxical measures are taken to satisfy the Israelachvili rules. They state that only inverted cone amphiphiles form soluble micelles in water, while inverted micelles from cone shaped amphiphiles precipitate into hexagonal 1 supramolecular polymers, and the intermediate cylindrical amphiphiles show intermediate behavior dominated by bilayers and lamellar precipitates. The normal micelles obtained from inverted cone flipper amphiphiles prevent precipitation and prepare for efficient transfer into the lipid bilayer membranes. The results are flippers that break all records set by the 2016 original with regard to effective brightness, responsiveness to membrane order, anchoring in disordered membranes, partitioning into membranes of high order, and stable labeling of membranes of interest. The lessons learned confirm the obvious: The Israelachvili rules apply also to fluorescent membrane probes. They promise literally bright perspectives for fluorescent membrane probes.","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 7","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400062","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140937609","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

Ambrox through the Looking Glass: Chemoenzymatic Synthesis and GC-Olfactometric Analysis of 15 Ambrox Stereoisomers 透过玻璃看氨溴索15 种氨溴索立体异构体的化学酶法合成和气相色谱-反应监测分析

IF 1.5 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-08 DOI: 10.1002/hlca.202400016

Felix Flachsmann, Natalie Aeberli, Sandro Dossenbach, Lucas Hortencio, Heinz Koch, Gerhard Brunner, Benjamin Spenger, Eric Eichhorn, Alessio Fonzo, Raphael Berweger, Dominique Lelièvre

{"title":"Ambrox through the Looking Glass: Chemoenzymatic Synthesis and GC-Olfactometric Analysis of 15 Ambrox Stereoisomers","authors":"Felix Flachsmann, Natalie Aeberli, Sandro Dossenbach, Lucas Hortencio, Heinz Koch, Gerhard Brunner, Benjamin Spenger, Eric Eichhorn, Alessio Fonzo, Raphael Berweger, Dominique Lelièvre","doi":"10.1002/hlca.202400016","DOIUrl":"10.1002/hlca.202400016","url":null,"abstract":"All eight theoretical stereoisomers of (10S)-Ambrox have been synthesized by enzymatic polycyclization of the four geometric isomers of homofarnesol with selected squalene hopene cyclases. This includes the highly strained (+)-(8S,9S)-Ambrox, an isomer historically considered unlikely to exist. The enantiomeric (10R)-series has been prepared by a combination of diastereoselective synthesis and preparative chiral HPLC. Thus, for the first time, the synthesis and sensory properties of all but one stereoisomers of Ambrox are presented. The results solve a long standing peradventure: the commercial product (−)-Ambrox exhibits by far the strongest odour, the previously described 9-epi-Ambrox is 26 times weaker. The enantiomer difference between (−)-and (+)-Ambrox was also found much higher than in previous reports (1000 vs. 8 times). The (8R)-configuration was identified as the single most important structural feature for high odour strength.","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 7","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140937599","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

Sustainable Twist – Towards Highly Atom Efficient Grignard Processes 可持续的扭转 - 实现高原子效率的格氏过程

IF 1.5 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-07 DOI: 10.1002/hlca.202400048

Philipp Kohler, Eva Kirchner, Emilia Păunescu, Ulrich Mayerhöffer

引用次数: 0

New Phases in the Sc−Mn−Si and Sc−Mn−Al−Si Systems Through Molten Indium Flux Synthesis 通过熔融铟助熔剂合成钪-锰-硅和钪-锰-铝-硅体系中的新物相

IF 1.8 4区化学

Helvetica Chimica Acta Pub Date : 2024-05-06 DOI: 10.1002/hlca.202400018

Robin Lefèvre, Felix Eder, Fabian O. von Rohr

{"title":"New Phases in the Sc−Mn−Si and Sc−Mn−Al−Si Systems Through Molten Indium Flux Synthesis","authors":"Robin Lefèvre, Felix Eder, Fabian O. von Rohr","doi":"10.1002/hlca.202400018","DOIUrl":"10.1002/hlca.202400018","url":null,"abstract":"Through the application of synthesis via molten indium flux, we have been able to expand the ternary Sc−Mn−Si system and the quaternary Sc−Mn−Al−Si system. Specifically, we report on five previously unknown chemical compounds, namely β-ScMnSi2, Sc4+xMn4Si7–2x, Sc2Mn4Si5, Sc2Mn3Si4, and Sc4Mn2AlSi4. The compounds with the stoichiometries Sc2Mn4Si5, Sc2Mn3Si4, and Sc4Mn2AlSi4 have previously not been reported. We find that these crystallize in the V6Si5, Hf2Ru3Si4, and Ho4Ni2InGe4 structure types, respectively. For the ternary compounds with the stoichiometries of ScMnSi2 and Sc4+xMn4Si7–2x, we find clearly deviating structural solutions compared to earlier reports. β-ScMnSi2 is found to crystallize in the monoclinic crystal system isostructural to a supercell of the MnTiSi2 structure and clearly deviating from the known orthorhombic α-polymorph. The compound Sc4+xMn4Si7–2x is structurally very similar to Sc4Mn4Si7, but exhibits the P4/nmm space group instead of I4/mmm, and is related to the Zr4Co4Ge7 structure. Disorder between Si and Sc sites leads to the off-stoichiometric composition, for which we found x=0.287(5).","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 6","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hlca.202400018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140888322","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

Advances in the Synthesis of Heterocycles with Two and Three Heteroatoms using Hydrazonoyl Halides 利用肼酰卤合成具有两个和三个杂原子的杂环的进展。

IF 1.5 4区化学

Helvetica Chimica Acta Pub Date : 2024-04-30 DOI: 10.1002/hlca.202400058

Nargiza R. Yamaletdinova, Rail R. Gataullin

{"title":"Advances in the Synthesis of Heterocycles with Two and Three Heteroatoms using Hydrazonoyl Halides","authors":"Nargiza R. Yamaletdinova, Rail R. Gataullin","doi":"10.1002/hlca.202400058","DOIUrl":"10.1002/hlca.202400058","url":null,"abstract":"The review covers the results of studies published in the literature on the use of hydrazonoyl halides in the synthesis of five- (pyrazoles, thiazoles, triazoles, oxa- and thiadiazoles), six- (oxa- and thiadiazines, indazoles, pyridazines, pyrazines, tetrazines) or seven-membered (benzotriazepine) heterocycles. In the formation of these heterocycles, the main intermediate stage of the reaction is the in situ generation of nitrilimine, which enters into a cycloaddition reaction with substituted acetylenes (including in situ generated benzynes, naphthynes), allenes, activated olefins, anthranilic acid derivatives, organosulfur compounds (mercaptoaldehydes, mercaptocarboxylic acids) or with fused heterocycles. Examples are given of the formation of heterocycles by replacing the halogen atom from a hydrazonoyl halide molecule with a nucleophilic group, followed by exhaustive intramolecular cyclization into the target compound. There are discussions of reactions in which the cycloaddition of the nitrilimine to the in situ synthesized Knoevenagel condensation product (from CH-acid compounds, such as di- and monocarbonyl compounds, dinitrile malonic acid) occurs, leading to spiro-linked or conventional pyrazoles. Some syntheses of biologically active representatives are shown.","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 7","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140828912","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

Atomic Tailoring of Ubiquitin Side Chains Influences E2-Mediated Ubiquitin Chain Formation 超泛素侧链的原子修饰影响 E2 介导的超泛素链形成

IF 1.5 4区化学

Helvetica Chimica Acta Pub Date : 2024-04-24 DOI: 10.1002/hlca.202400003

Haewon Song, Toshiki Mikami, Sohei Majima, Jeffrey W. Bode

{"title":"Atomic Tailoring of Ubiquitin Side Chains Influences E2-Mediated Ubiquitin Chain Formation","authors":"Haewon Song, Toshiki Mikami, Sohei Majima, Jeffrey W. Bode","doi":"10.1002/hlca.202400003","DOIUrl":"10.1002/hlca.202400003","url":null,"abstract":"Ubiquitin (Ub) is a small, highly conserved protein essential for eukaryotic biology, and is unique in its formation of polyubiquitin chains by conjugation to one of its seven lysine side chains. Here we report that atomic tailoring of Ub side chains – i. e. the insertion, deletion, or replacement of specific atoms – has significant and unexpected consequences on the enzymatic conjugation of Ub oligomers by isopeptide bond formation mediated by E2 conjugating enzymes. These studies employed chemical synthesis and ligation methods to prepare numerous specifically tailored Ub monomers on multi-milligram scales. While some modifications including N-terminal acylation and methionine replacement did not affect protein folding or Ub chain formation with Ube2 K, other modifications had a pronounced effect of oligomerization with Ubc13/Mms2. We observed that Ala46Hse mutation obliterates the ability of this Ub monomer to accept another Ub at Lys63 in Ubc13-mediated conjugations. Exhaustive replacement of all seven lysines with shorter surrogates Orn, Dab, or Dap essentially blocks Ub chain formation, and in the case of Dap, precludes proper folding of the Ub protein.","PeriodicalId":12842,"journal":{"name":"Helvetica Chimica Acta","volume":"107 7","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140661424","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 4/2024) 封面图片： (Helv. Chim. Acta 4/2024)

IF 1.8 4区化学

Helvetica Chimica Acta Pub Date : 2024-04-15 DOI: 10.1002/hlca.202470401

引用次数: 0