Tetrahedron Letters最新文献_第4页

Streptavidin binding stoichiometry of biotinylated silicon phthalocyanines: impact of axial ligands 生物素化硅酞菁链亲和素结合化学计量学：轴向配体的影响

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-11 DOI: 10.1016/j.tetlet.2025.155711

Takahiko Matsushita , Kanna Saito , Kengo Inagaki , Tetsuo Koyama , Ken Hatano , Koji Matsuoka

{"title":"Streptavidin binding stoichiometry of biotinylated silicon phthalocyanines: impact of axial ligands","authors":"Takahiko Matsushita , Kanna Saito , Kengo Inagaki , Tetsuo Koyama , Ken Hatano , Koji Matsuoka","doi":"10.1016/j.tetlet.2025.155711","DOIUrl":"10.1016/j.tetlet.2025.155711","url":null,"abstract":"<div><div>Biotinylated silicon phthalocyanines (SiPcs) represent promising platforms for targeted molecular systems that engage streptavidin through high-affinity biotin–protein interactions. In this study, two SiPc derivatives were synthesized with biotin appended via distinct axial ligands. Although both compounds exhibited similar optical properties in dimethyl sulfoxide, their binding behavior with streptavidin differed markedly. A competitive displacement assay using 4′-hydroxyazobenzene-2-carboxylic acid revealed that compound <strong>1</strong> occupied approximately 3.5 binding pockets per streptavidin tetramer, whereas compound <strong>2</strong> showed negligible displacement even at high concentrations. SDS-PAGE analysis confirmed that the streptavidin tetramer remained intact in the presence of compound <strong>1</strong>, ruling out tetramer dissociation as a cause of sub-stoichiometric binding. These findings indicate that steric hindrance or limited spatial accessibility of the biotin moiety, possibly compounded by aggregation in aqueous media, critically impacts functional binding. This study demonstrates that the architecture of axial ligands affects the effective presentation of biotin on SiPc scaffolds and informs the design of supramolecular probes and photofunctional systems responsive to biological targets.</div></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":"168 ","pages":"Article 155711"},"PeriodicalIF":1.5,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144289195","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

CuCl-mediated desulfurization reactions of Dithiocarbamate Triethylamine salts: Access to 2-Aminooxazolines and Thioureas, and their synthetic applications cucl介导的二硫代氨基甲酸三乙胺盐的脱硫反应：2-氨基恶唑啉和硫脲的获得及其合成应用

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-11 DOI: 10.1016/j.tetlet.2025.155710

Jian-Hao Zhou, Fei-Yun Bao, Sheng-Yin Zhao

引用次数: 0

Synthesis of C22-C28 substituted Tetrahydropyran fragment of Eribulin 萘布林C22-C28取代四氢吡喃片段的合成

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-10 DOI: 10.1016/j.tetlet.2025.155708

Mahender Khatravath , Naveen Kumar Mallurwar , Javed Iqbal , Prabhat Arya

引用次数: 0

Synthesis of bacteriochlorophyll-c analogs possessing thio-functionalized substituents at the 20-position and their self-aggregation 在20位具有硫代功能化取代基的细菌叶绿素-c类似物的合成及其自聚集

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-09 DOI: 10.1016/j.tetlet.2025.155693

Kana Sakaguchi , Shin Ogasawara , Yamato Hashimoto, Hitoshi Tamiaki

{"title":"Synthesis of bacteriochlorophyll-c analogs possessing thio-functionalized substituents at the 20-position and their self-aggregation","authors":"Kana Sakaguchi , Shin Ogasawara , Yamato Hashimoto, Hitoshi Tamiaki","doi":"10.1016/j.tetlet.2025.155693","DOIUrl":"10.1016/j.tetlet.2025.155693","url":null,"abstract":"<div><div>Methyl pyropheophorbides-<em>a</em> possessing some substituents at the 3-position as chlorophyll-<em>a</em> derivatives were regioselectively trifluoromethylthiolated and thiocyanated at the 20-position by heating with <em>N</em>-trifluoromethylthio- and thiocyanato-dibenzenesulfonimide, respectively, in <em>N</em>,<em>N</em>-dimethylformamide. Based on the novel thio-functionalization at the 20-position, zinc methyl 3-hydroxymethyl-pyropheophorbides-<em>a</em> bearing the 20-SCF<sub>3</sub> or SCN group were prepared as the models of naturally occurring bacteriochlorophyll(BChl)-<em>c</em> with the 20-Me group. The resulting model compounds self-aggregated in an aqueous Triton X-100 micellar solution to give red-shifted and broadened electronic absorption bands, similar to the self-aggregation of BChl-<em>c</em> in chlorosomes, major light-harvesting antennae of photosynthetic green bacteria. The electronic and steric effects of the 20-SX groups on the absorption bands of their monomeric and aggregated states as well as their self-aggregation abilities are discussed.</div></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":"168 ","pages":"Article 155693"},"PeriodicalIF":1.5,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271703","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

Mild aerobic oxidation of alcohols to carbonyl compounds with ferric nitrate Nonahydrate in Trifluoroacetic acid 用硝酸铁在三氟乙酸中轻度有氧氧化制羰基化合物

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-09 DOI: 10.1016/j.tetlet.2025.155687

Yuan Zhang, Zhi-Xin Guo, Pu Zhang

引用次数: 0

[Bis(trifluoroacetoxy)iodo]benzene mediated regioselectivec(sp2)–H selenylation of α-oxo ketene dithioacetals under ambient conditions [双（三氟乙酰氧基）碘]苯介导的α-氧酮二硫缩醛的区域选择性(sp2) -H硒化反应

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-06 DOI: 10.1016/j.tetlet.2025.155685

Anirban Mandal, Sanjay Roy, Sajal Das

引用次数: 0

Recent advances in the Newman–Kwart rearrangement 纽曼-沃特重排的最新进展

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-06 DOI: 10.1016/j.tetlet.2025.155690

Tetsuhiro Nemoto, Yuma Okuda, Keita Yamazaki

{"title":"Recent advances in the Newman–Kwart rearrangement","authors":"Tetsuhiro Nemoto, Yuma Okuda, Keita Yamazaki","doi":"10.1016/j.tetlet.2025.155690","DOIUrl":"10.1016/j.tetlet.2025.155690","url":null,"abstract":"<div><div>Since its independent development by Newman and Kwart in the 1960s, the Newman–Kwart rearrangement has been extensively studied for synthesizing thiophenols. A major limitation of this reaction is the requirement for high temperatures. However, recently developed methods have significantly improved its synthetic utility. The method developed by Lloyd-Jones et al., which employs a Pd catalyst, successfully lowered the reaction temperature to around 100 °C by utilizing a reaction mechanism that proceeds via oxidative addition of the C<img>O bond of <em>O</em>-aryl thiocarbamates. The single-electron oxidation approach introduced by Nicewicz et al. enabled the Newman–Kwart rearrangement to proceed at room temperature and significantly expanded its substrate scope. This strategy, based on the generation of electrophilic thiyl radical intermediates, was further extended to the development of Newman–Kwart rearrangement protocols using Ce or Fe oxidants, as well as electrochemical approaches. More recently, a reaction system employing a Bi catalyst has been developed to facilitate the Newman–Kwart rearrangement of <em>O-</em>heteroaryl thiocarbamates at room temperature. This paper provides an overview of the recent advances in this field.</div></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":"168 ","pages":"Article 155690"},"PeriodicalIF":1.5,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255221","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

Hydrophobic-pocket-enabled organocatalysis: New stereodirecting diphenylethylenediamine-isosteviol thioureas for accelerated michael addition under green aqueous conditions 疏水口袋型有机催化：新型立体定向二苯乙二胺-异甜菊醇硫脲在绿色水溶液条件下加速迈克尔加成

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-06 DOI: 10.1016/j.tetlet.2025.155689

Yuxia Liu, Mingyang Lv, Zhaoyang Fan, Qi Liu, Xinyu Dai

引用次数: 0

The design and synthesis of a novel α-alkynylated biotin scaffold for use in heterobifunctional molecular probes 用于异功能分子探针的新型α-炔基化生物素支架的设计与合成

IF 1.5 4区化学

Tetrahedron Letters Pub Date : 2025-06-05 DOI: 10.1016/j.tetlet.2025.155692

Jack W. Annear , Michael J. Nutt , Gavin R. Flematti , Joseph Rosenbluh , Scott G. Stewart

引用次数: 0

Tandem Pictet-Spengler/oxidation reaction: One-step synthesis of β-carbolines oxidized by Ca(ClO)2 串联Pictet-Spengler/氧化反应：Ca(ClO)2氧化一步合成β-碳胺