Tetrahedron chem最新文献_第10页

Concise chemoenzymatic total synthesis of (−)-rubroskyrin, (−)-deoxyrubroskyrin (−)-luteoskyrin, and (−)-deoxyluteoskyrin （−）-红曲霉毒素、（−）脱氧红曲霉毒素

Tetrahedron chem Pub Date : 2022-08-01 DOI: 10.1016/j.tchem.2022.100030

Amit Mondal, Nirmal Saha, Syed Masood Husain

{"title":"Concise chemoenzymatic total synthesis of (−)-rubroskyrin, (−)-deoxyrubroskyrin (−)-luteoskyrin, and (−)-deoxyluteoskyrin","authors":"Amit Mondal, Nirmal Saha, Syed Masood Husain","doi":"10.1016/j.tchem.2022.100030","DOIUrl":"10.1016/j.tchem.2022.100030","url":null,"abstract":"<div><p>Synthesis of complex dimeric natural products (−)-luteoskyrin and (−)-deoxyluteoskyrin isolated from <em>P. islandicum</em> Sopp nearly 70 years ago, remained a challenge until now. Their biosynthesis had been proposed to involve dimerization using a putative intermediate dihydrocatenarin as a key step. In the current work, we employed a chemoenzymatic strategy to synthesize (<em>R</em>)-dihydrocatenarin using an anthrol reductase of <em>T. islandicus</em>. Its homodimerization in the presence of molecular oxygen gave (−)-rubroskyrin, which on Michael reaction led to the first total synthesis of (−)-luteoskyrin in an overall yield of 21%. In contrast, the heterodimerization between (<em>R</em>)-dihydrocatenarin and (<em>R</em>)-dihydroemodin led to non-natural, (−)-deoxyrubroskyrin analogue, while the use of molecular oxygen gave natural (−)-deoxyrubroskyrin. Both (−)-deoxyrubroskyrin and its analogue on treatment with pyridine gave (−)-deoxyluteoskyrin with an overall yield of up to 10%. The presence of dihydrocatenarin in <em>P. islandicum</em> NRRL 1036 culture is verified through mass spectrometry, which implied a similar biosynthetic pathway.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"3 ","pages":"Article 100030"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X22000262/pdfft?md5=f15e18f246db763dcdba312d885e7fae&pid=1-s2.0-S2666951X22000262-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47024528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Unsymmetric monothiooxalamides from S8, bromodifluoro reagents and anilines: Synthesis and applications S8、溴二氟试剂和苯胺的非对称单硫代草酰胺的合成与应用

Tetrahedron chem Pub Date : 2022-08-01 DOI: 10.1016/j.tchem.2022.100026

Xingxing Ma , Shuilin Deng , Jinchao Liang , Jinglong Chen , Jianke Su , Hua Huang , Qiuling Song

{"title":"Unsymmetric monothiooxalamides from S8, bromodifluoro reagents and anilines: Synthesis and applications","authors":"Xingxing Ma , Shuilin Deng , Jinchao Liang , Jinglong Chen , Jianke Su , Hua Huang , Qiuling Song","doi":"10.1016/j.tchem.2022.100026","DOIUrl":"10.1016/j.tchem.2022.100026","url":null,"abstract":"<div><p>Unsymmetric monothiooxamides as very special and important scaffolds have been widely existing in natural products and bioactive molecules. However, the efficient construction of such compounds are very rare. Herein, we report a simple and practical strategy to achieve unsymmetric monothiooxalamides via S<sub>8</sub>-mediated defluorination and vulcanization of amines with bromodifluoroalkylative reagents under mild conditions. And the potential applications of such compounds as ligands has been demonstrated in Cu-catalyzed cross coupling reactions. The fluorinated quinoxalinones, benzooxazinone, α-phenyliminoamides, as well as 2-amidobenzothiazoles are obtained <em>in-situ</em> from unsymmetric monothiooxalamides, in which bromodifluoroalkylative reagents undertake selective triple cleavage. Moreover, we also discover that <em>N</em>-aryl-2-amidobenzothiazoles have aggregation-induced luminescence (AIE) characteristics, which might have great potential in the fields of sensing, imaging, diagnosis and treatment.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"3 ","pages":"Article 100026"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X22000225/pdfft?md5=b1386a90e4ef3e2ff812335c371d3155&pid=1-s2.0-S2666951X22000225-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43503176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Palladium-catalyzed regio- and stereoselective alkoxycarbonylation of unsymmetrical internal alkynes toward α, β-unsaturated succinates 钯催化不对称内炔向α， β-不饱和琥珀酸酯的区域和立体选择性烷氧羰基化反应

Tetrahedron chem Pub Date : 2022-08-01 DOI: 10.1016/j.tchem.2022.100029

Chang-Sheng Kuai , Bing-Hong Teng , Yingying Zhao , Xiao-Feng Wu

引用次数: 3

Madangamine alkaloids: Madness and tranquility 马丹加明生物碱：疯狂与宁静

Tetrahedron chem Pub Date : 2022-08-01 DOI: 10.1016/j.tchem.2022.100025

Ye Tang , Lili Zhu , Ran Hong

引用次数: 1

Ligand-enabled C–H borylation of diverse classes of arenes 不同种类芳烃的配体活化C-H硼化反应

Tetrahedron chem Pub Date : 2022-08-01 DOI: 10.1016/j.tchem.2022.100028

Md Emdadul Hoque , Sayan Dey , Mirja Md Mahamudul Hassan , Jagriti Chaturvedi , Saikat Guria , Jaitri Das , Brindaban Roy , Buddhadeb Chattopadhyay

引用次数: 1

Nickel-catalyzed enantioselective domino Heck/Sonogashira coupling for construction of C(sp)-C(sp [ ]) bond-substituted quaternary carbon centers 镍催化对映选择性domino-Heck/Sonogashira偶联构建C（sp）-C（sp[]）键取代的季碳中心

Tetrahedron chem Pub Date : 2022-07-01 DOI: 10.1016/j.tchem.2022.100021

Hui Chen, Zhenkang Ai, Lingmei Guo, Licheng Yao, yaopeng Li, Bu-Ming Gu, Yixuan Zhang, Yahu A. Liu, Boxue Tian, X. Liao

引用次数: 2

Indacenodipyrene containing small molecules and ladder polymers 含有小分子和阶梯聚合物的吲哚二芘

Tetrahedron chem Pub Date : 2022-06-01 DOI: 10.1016/j.tchem.2022.100019

Ain Uddin, Krishna Pandey, Kyle N. Plunkett

引用次数: 0

‘Pincer-tweezer’ tetraimidazolium salts as hosts for halides “钳-镊子”四胺唑盐作为卤化物的宿主

Tetrahedron chem Pub Date : 2022-06-01 DOI: 10.1016/j.tchem.2022.100018

Esteban Valencia, Macarena Poyatos, Eduardo Peris

{"title":"‘Pincer-tweezer’ tetraimidazolium salts as hosts for halides","authors":"Esteban Valencia, Macarena Poyatos, Eduardo Peris","doi":"10.1016/j.tchem.2022.100018","DOIUrl":"10.1016/j.tchem.2022.100018","url":null,"abstract":"<div><p>In this work we describe the preparation of two tetracationic molecular tweezers that were used as hosts for the recognition of chloride, bromide and iodide. These two hosts contain a rigid bis-alkynyl spacer that connects two arms built with two pincer bis-imidazolium units. The nature of the spacer confers distinct structural features to these two molecular ‘pincer-tweezers’. The tweezer with the anthracenyl linker has a quasi-parallel disposition of the two arms of the tweezer, while in the carbazolyl-linked tweezer the two arms are significantly more separated. The study of the binding affinities of these two hosts with the three target halides showed substantial differences depending on the tetra-imidazolium tweezer used. In particular, the carbazolyl-based tweezer follows a 1:2 host:guest binding model, while the binding of the anthracenyl-linked tweezer is best explained using a 1:1 model. The different behavior is ascribed to the subtle different structural features of the two tetra-azolium receptors. The comparison of the affinities of the two tetracationic hosts with the related bis-imidazolium mono-pincer host indicates significantly enhanced association constants shown by the pincer-tweezer hosts, which are ascribed to a combination of the larger electrostatic attraction provided by the use of the tetracations together with the converging orientation of the two pincer bis-imidazoliums in the structure of the tweezers. These new tweezer-shaped tetra-imidazolium receptors are significantly different to other traditional tetrazoliums used as hosts for anions, which are mostly based on cyclic and more flexible structures. The pincer-tweezer hosts are acyclic and nevertheless more rigid than most of the poly-azolium-based receptors used until now.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"2 ","pages":"Article 100018"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X22000146/pdfft?md5=46f96d5735ee45c999a9b5003c042b4d&pid=1-s2.0-S2666951X22000146-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49494062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Asymmetric organocatalysis involving double activation 涉及双重活化的不对称有机催化

Tetrahedron chem Pub Date : 2022-06-01 DOI: 10.1016/j.tchem.2022.100017

Zhi Chen , Qian-Qian Yang , Wei Du , Ying-Chun Chen

{"title":"Asymmetric organocatalysis involving double activation","authors":"Zhi Chen , Qian-Qian Yang , Wei Du , Ying-Chun Chen","doi":"10.1016/j.tchem.2022.100017","DOIUrl":"10.1016/j.tchem.2022.100017","url":null,"abstract":"<div><p>Asymmetric organocatalysis contributed tremendously to the field of organic synthesis since year 2000. Considering the diversity of organocatalysts and their activation modes, chemists developed the double activation strategy, in which two distinct catalysts simultaneously interact with a single substrate, thus enabling effective transformations that might be too challenging or even unattainable under a sole catalytic system. This review summarized the asymmetric reactions via double activation catalysis involving different Lewis bases (aminocatalysts, <em>N</em>-heterocyclic carbenes, isothioureas, <em>N</em>,<em>N</em>-dimethyl-4-aminopyridine, tertiary amines/phosphines, or even thiols), Brønsted bases (including phase transfer catalysts), Brønsted acids, and a few examples combining organocatalysts and metal catalysts or photocatalysts were also discussed. In most cases, compared to those with a single catalyst, better reactivity and stereoselectivity, or even completely different regioselectivity or chemoselectivity were observed under double activation catalysis, demonstrating the power and superiority of this promising strategy. Some key intermediates as well as the mechanisms have been presented to provide insights into the activation processes, which might inspire the development of new double activation systems and more interesting work in the future.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"2 ","pages":"Article 100017"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X22000134/pdfft?md5=156b863f4a1eb2ad4c0f544729554091&pid=1-s2.0-S2666951X22000134-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46765496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Collective total syntheses of cytochalasans and merocytochalasans 细胞松弛素和亚细胞松弛素的集体全合成

Tetrahedron chem Pub Date : 2022-06-01 DOI: 10.1016/j.tchem.2022.100022

Haoyu Zhang, Jingyang Zhang, Ruiyang Bao, Chong Tian, Yefeng Tang

{"title":"Collective total syntheses of cytochalasans and merocytochalasans","authors":"Haoyu Zhang, Jingyang Zhang, Ruiyang Bao, Chong Tian, Yefeng Tang","doi":"10.1016/j.tchem.2022.100022","DOIUrl":"10.1016/j.tchem.2022.100022","url":null,"abstract":"<div><p>Cytochalasans are an important class of fungal metabolites displaying remarkable structural diversity and significant biological activity. Historically, considerable effort has been devoted toward the synthesis of cytochalasans. Comparably, merocytochalasans, an array of more complicated molecules biosynthetically derived from cytochalasans and epicoccine through hetero-dimerization, -trimerization or -tetramerization, have been less explored. In recent years, our group has shown keen interest on cytochalasans and merocytochalasans, which has culminated in the collective syntheses of a variety of representative molecules of this family. To this end, we first developed a highly concise, efficient and modular approach to access 11/6/5 tricyclic cytochalasans, featuring an intermolecular Diels-Alder reaction and a ring-closing metathesis reaction as key steps. Based on this synthetic route, several cytochalasan monomers, including aspochalasin B, aspochalasin P, aspochalasin D and aspergillin PZ, have been synthesized within 11–14 longest linear steps. Subsequently, a couple of hetero-dimeric and -trimeric merocytochalasans, including asperchalasines A-E and asperflavipine B, have been accessed from aspochalasin B and the suitable epicoccine precursors through a series of intriguing bio-inspired transformations such as Diels-Alder reaction and formal [5 + 2] cycloaddition. Moreover, the full profile of the regio- and <em>endo</em>/<em>exo</em> selectivity of the Diels-Alder heterodimerization has been explored through computational study. The present study not only notably enriches the synthetic chemistry of cytochalasans and merocytochalasans, but also affords venerable clue to decipher the biosynthetic origins of the newly identified merocytochalasans.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"2 ","pages":"Article 100022"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X22000183/pdfft?md5=885d87d2b823c8ab26a2ab37f8059d76&pid=1-s2.0-S2666951X22000183-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43436118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0