Nian-Xuan Lin, Shih-Ming Chang, Xin-Shun Chiou, Kelly Lee, Yu-Tung Tsai, Prof. Dr. Cheng-Kun Lin
In article number e202400188, Cheng-Kun Lin and co-workers present a method to convert epoxy carbamates to oxazolidinones by combining intermolecular nucleophilic epoxide ring opening with intramolecular acyl substitution in a single step, enabling rapid conversion. It demonstrates favourable reactivity across various aryl groups, benzyl, or tert-butyl carbamates, consistently yielding satisfactory results, with oxazolidinone formation ranging from 55% to 99% across over 24 examples.
{"title":"Front Cover: Rapidly Diverse Synthesis of N-Aryl-5-Substituted-2-Oxazolidinones via Nucleophilic Epoxide Ring Opening and Intramolecular Acyl Substitution of Epoxy Carbamates (Asian J. Org. Chem. 9/2024)","authors":"Nian-Xuan Lin, Shih-Ming Chang, Xin-Shun Chiou, Kelly Lee, Yu-Tung Tsai, Prof. Dr. Cheng-Kun Lin","doi":"10.1002/ajoc.202480901","DOIUrl":"https://doi.org/10.1002/ajoc.202480901","url":null,"abstract":"<p>In article number e202400188, Cheng-Kun Lin and co-workers present a method to convert epoxy carbamates to oxazolidinones by combining intermolecular nucleophilic epoxide ring opening with intramolecular acyl substitution in a single step, enabling rapid conversion. It demonstrates favourable reactivity across various aryl groups, benzyl, or tert-butyl carbamates, consistently yielding satisfactory results, with oxazolidinone formation ranging from 55% to 99% across over 24 examples.\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajoc.202480901","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233196","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}
Catalytic kinetic resolutions of racemic carboxylic acids are important methods for preparing chiral carboxylic acids in their optically active forms. While several effective methods for the catalytic kinetic resolution of chiral α‐tertiary carboxylic acids have been reported, the efficient kinetic resolution of α‐quaternary carboxylic acids remains a significant challenge. In this context, we aimed to develop methods for the kinetic resolution of α‐quaternary carboxylic acids. Our approach involves a BINOL‐derived chiral bifunctional sulfide‐catalyzed bromolactonization technique, which was developed by our research group. In this work, we report the kinetic resolution of α‐allyl‐α‐cinnamyl carboxylic acids bearing an α‐quaternary stereocenter via chemo‐ and stereoselective bromolactonizations. The use of a BINOL‐derived chiral bifunctional sulfide catalyst with a hydroxy group was key for the efficient kinetic resolution of racemic α‐allyl‐α‐cinnamyl carboxylic acids.
{"title":"Kinetic Resolution of α‐Allyl‐α‐cinnamyl Carboxylic Acids Bearing an All‐Carbon Quaternary Stereocenter via Bromolactonization Catalyzed by a Chiral Bifunctional Sulfide","authors":"Ken Okuno, Sao Sumida, Seiji Shirakawa","doi":"10.1002/ajoc.202400405","DOIUrl":"https://doi.org/10.1002/ajoc.202400405","url":null,"abstract":"Catalytic kinetic resolutions of racemic carboxylic acids are important methods for preparing chiral carboxylic acids in their optically active forms. While several effective methods for the catalytic kinetic resolution of chiral α‐tertiary carboxylic acids have been reported, the efficient kinetic resolution of α‐quaternary carboxylic acids remains a significant challenge. In this context, we aimed to develop methods for the kinetic resolution of α‐quaternary carboxylic acids. Our approach involves a BINOL‐derived chiral bifunctional sulfide‐catalyzed bromolactonization technique, which was developed by our research group. In this work, we report the kinetic resolution of α‐allyl‐α‐cinnamyl carboxylic acids bearing an α‐quaternary stereocenter via chemo‐ and stereoselective bromolactonizations. The use of a BINOL‐derived chiral bifunctional sulfide catalyst with a hydroxy group was key for the efficient kinetic resolution of racemic α‐allyl‐α‐cinnamyl carboxylic acids.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142217077","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}
A fluorescence‐labeled nucleotide with a cleavable triazene linker was designed and synthesized as a potential reversible terminator for DNA sequencing by synthesis (SBS). The key intermediate, a triazene‐modified nucleotide, was successfully synthesized through the triazenylation of an amino‐modified nucleotide, followed by fluorescence labeling to yield the desired product. The synthesized triazene‐modified nucleotide can effectively serve as a substrate for Klenow Fragment (exo‐) DNA polymerase and be incorporated into DNA strands. Once the first modified nucleotide is incorporated, no further extension is possible, even with an unblocked 3'‐OH group. After the fluorescent label is completely removed under acidic conditions, the triazene reversible terminator can be incorporated into DNA strands again, thereby enabling the DNA sequencing cycles.
我们设计并合成了一种带有可裂解三氮烯连接体的荧光标记核苷酸，作为 DNA 合成测序（SBS）的潜在可逆终止子。通过对氨基修饰的核苷酸进行三嗪化，然后进行荧光标记，成功合成了关键的中间体--三嗪修饰的核苷酸，并得到了所需的产物。合成的三嗪修饰核苷酸可以有效地作为克伦诺片段（外）DNA 聚合酶的底物，并被整合到 DNA 链中。一旦第一个修饰的核苷酸被整合进去，就不可能再进一步延伸，即使是未被阻断的 3'-OH 基团也是如此。在酸性条件下，荧光标签被完全去除后，三嗪可逆终止剂可再次与 DNA 链结合，从而实现 DNA 测序循环。
{"title":"Synthesis and Evaluations of Cleavable Triazene‐Modified Nucleotide for DNA Sequencing","authors":"Pingyang Wang, Bowei Tang, Yu-Mei Shen","doi":"10.1002/ajoc.202400393","DOIUrl":"https://doi.org/10.1002/ajoc.202400393","url":null,"abstract":"A fluorescence‐labeled nucleotide with a cleavable triazene linker was designed and synthesized as a potential reversible terminator for DNA sequencing by synthesis (SBS). The key intermediate, a triazene‐modified nucleotide, was successfully synthesized through the triazenylation of an amino‐modified nucleotide, followed by fluorescence labeling to yield the desired product. The synthesized triazene‐modified nucleotide can effectively serve as a substrate for Klenow Fragment (exo‐) DNA polymerase and be incorporated into DNA strands. Once the first modified nucleotide is incorporated, no further extension is possible, even with an unblocked 3'‐OH group. After the fluorescent label is completely removed under acidic conditions, the triazene reversible terminator can be incorporated into DNA strands again, thereby enabling the DNA sequencing cycles.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216967","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}
Nagula Shankaraiah, Mursalim A. Khan, Rajkumar Reddyrajula, Akash P. Sakla, Manda Sathish
The synthesis of tetrahydro-β-carbolines (THβCs) framework is a fundamental aspect of medicinal chemistry due to their significant pharmacological applications. Herein, we developed a microwave-assisted novel approach for the synthesis of THβC scaffolds utilizing ferrous(II) chloride as an earth abundant metal catalyst and methanol used as valuable methylene source. This methodology demonstrates excellent functional group tolerance and provides N2-substituted THβCs in good to excellent yields. Overall, this study highlights a sustainable and practical strategy for the synthesis of biologically important THβCs, thereby offering promising prospects in the drug discovery and development.
{"title":"Microwave-Assisted One-pot Synthesis of Tetrahydro-β-Carbolines by Fe(II)-Catalyst: Utilizing Methanol as Methylene Synthon","authors":"Nagula Shankaraiah, Mursalim A. Khan, Rajkumar Reddyrajula, Akash P. Sakla, Manda Sathish","doi":"10.1002/ajoc.202400404","DOIUrl":"https://doi.org/10.1002/ajoc.202400404","url":null,"abstract":"The synthesis of tetrahydro-β-carbolines (THβCs) framework is a fundamental aspect of medicinal chemistry due to their significant pharmacological applications. Herein, we developed a microwave-assisted novel approach for the synthesis of THβC scaffolds utilizing ferrous(II) chloride as an earth abundant metal catalyst and methanol used as valuable methylene source. This methodology demonstrates excellent functional group tolerance and provides N2-substituted THβCs in good to excellent yields. Overall, this study highlights a sustainable and practical strategy for the synthesis of biologically important THβCs, thereby offering promising prospects in the drug discovery and development.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216971","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}
Herein, we report a photoredox‐catalyzed fluoroalkylation of activated alkenes via fluorinated alkyl‐centered radical induced radical addition/annulation/SET/deprotonation in a domino fashion using 4CzIPN as photocatalyst. The protocol features room temperature, transition metal free, high yields and simple operation, affording a facile and efficient strategy to access fluorine‐containing naphthalenone.
{"title":"Synthesis of Naphthalenones via Photo‐Induced Radical Cascade Fluoroalkylation/Cyclization of Alkenes","authors":"Xiaohu Yang, Chunmei Yang, Xiaoqing Wan, Wen-Chao Yang, Hegui Fang, Wenchao Yang","doi":"10.1002/ajoc.202400354","DOIUrl":"https://doi.org/10.1002/ajoc.202400354","url":null,"abstract":"Herein, we report a photoredox‐catalyzed fluoroalkylation of activated alkenes via fluorinated alkyl‐centered radical induced radical addition/annulation/SET/deprotonation in a domino fashion using 4CzIPN as photocatalyst. The protocol features room temperature, transition metal free, high yields and simple operation, affording a facile and efficient strategy to access fluorine‐containing naphthalenone.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216969","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}
Nanfang Wang, Wozheng Fang, Yu Yan, Nan Sun, Junbiao Chang, Xiao-Na Wang
A TMSOTf‐catalyzed annulation was developed for the construction of polysubstituted maleimides from ynamides and alkynyl sulfoxides, using oxygen as a green oxidant and ynamides as both carbon and nitrogen sources. This novel protocol proceeds in the presence of TMSOTf without the need for an expensive catalytic system and tolerates a broad substrate scope, providing a variety of maleimides in generally moderate to good yields under mild reaction conditions.
{"title":"TMSOTf‐Catalyzed Annulation of Ynamides with Alkynyl Sulfoxides to Construct Substituted Maleimides","authors":"Nanfang Wang, Wozheng Fang, Yu Yan, Nan Sun, Junbiao Chang, Xiao-Na Wang","doi":"10.1002/ajoc.202400416","DOIUrl":"https://doi.org/10.1002/ajoc.202400416","url":null,"abstract":"A TMSOTf‐catalyzed annulation was developed for the construction of polysubstituted maleimides from ynamides and alkynyl sulfoxides, using oxygen as a green oxidant and ynamides as both carbon and nitrogen sources. This novel protocol proceeds in the presence of TMSOTf without the need for an expensive catalytic system and tolerates a broad substrate scope, providing a variety of maleimides in generally moderate to good yields under mild reaction conditions.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216972","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}
Borylated indoles are versatile building blocks for functional molecules, such as pharmaceutical and natural products. However, the C−H borylation regioselectivity of unprotected indoles with seven distinct sites has been a problem for a long time. Among the various synthetic approaches to borylated indoles, transition‐metal‐catalyzed, electrophilic C−H borylation and chelation effect directed C−H borylation are attractive methods because of their powerful ability to rapidly construct various C−H borylation of indoles. In this review, we highlight the developments in the C−H borylation regioselectivity of indole using these methods of C−H borylation over the last 20 years. With a focus on the mechanism of the C−H borylation of indole, further studies and developments of this field would be inspired in the future.
{"title":"Recent Advances on Regioselective C−H Borylation of Indoles","authors":"Guodu Liu, Yanyan Guo, Meiyu Wang","doi":"10.1002/ajoc.202400464","DOIUrl":"https://doi.org/10.1002/ajoc.202400464","url":null,"abstract":"Borylated indoles are versatile building blocks for functional molecules, such as pharmaceutical and natural products. However, the C−H borylation regioselectivity of unprotected indoles with seven distinct sites has been a problem for a long time. Among the various synthetic approaches to borylated indoles, transition‐metal‐catalyzed, electrophilic C−H borylation and chelation effect directed C−H borylation are attractive methods because of their powerful ability to rapidly construct various C−H borylation of indoles. In this review, we highlight the developments in the C−H borylation regioselectivity of indole using these methods of C−H borylation over the last 20 years. With a focus on the mechanism of the C−H borylation of indole, further studies and developments of this field would be inspired in the future.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216968","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}
An efficient method for the activation of non‐activated cyclopropyl esters is developed using a hypervalent iodine(III) species and Selectfluor for the generation of acyl fluoride intermediates. The reactive acyl fluoride intermediate is smoothly transformed into various functional groups such as amides, esters, thioesters, and ketones depending on the nucleophile used in the in‐situ transformation. Utilizing the oxidation process of an iodoarene by Selectfluor, the activation is improved from a stoichiometric to catalytic protocol. Furthermore, the activation is employed in the chemoselective activation of target cyclopropyl ester in the presence of other ester moieties.
{"title":"Metal‐Free Generation of Acyl Fluorides via Activation of Cyclopropyl Esters using a Hypervalent Iodine(III) Species and Selectfluor.","authors":"Eun-sol Choi, Hyo-Jun Lee, Maruoka Keiji","doi":"10.1002/ajoc.202400398","DOIUrl":"https://doi.org/10.1002/ajoc.202400398","url":null,"abstract":"An efficient method for the activation of non‐activated cyclopropyl esters is developed using a hypervalent iodine(III) species and Selectfluor for the generation of acyl fluoride intermediates. The reactive acyl fluoride intermediate is smoothly transformed into various functional groups such as amides, esters, thioesters, and ketones depending on the nucleophile used in the in‐situ transformation. Utilizing the oxidation process of an iodoarene by Selectfluor, the activation is improved from a stoichiometric to catalytic protocol. Furthermore, the activation is employed in the chemoselective activation of target cyclopropyl ester in the presence of other ester moieties.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142217006","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}
Wenbo Ma, Tao Zheng, Zihan Yu, Junlong Li, Qilin Gu, Linghui Gu, Zheyu Li
A mechanochemical cross‐dehydrogenative coupling reaction of pyrazolones with thiols using ball milling is described. Benzeneselenol and dichalcogenide substrates are also compatible under mild reaction conditions, yielding up to 99%. Notable features of this reaction include its metal‐ and solvent‐free, wide substrate scope and good functional group tolerance. Preliminary mechanistic investigations suggest that a radical pathway is likely involved in this C‒H chalcogenation reaction
{"title":"Solvent‐Free Dehydrogenative C‒H Chalcogenations of Pyrazolones Using Mechanochemistry","authors":"Wenbo Ma, Tao Zheng, Zihan Yu, Junlong Li, Qilin Gu, Linghui Gu, Zheyu Li","doi":"10.1002/ajoc.202400353","DOIUrl":"https://doi.org/10.1002/ajoc.202400353","url":null,"abstract":"A mechanochemical cross‐dehydrogenative coupling reaction of pyrazolones with thiols using ball milling is described. Benzeneselenol and dichalcogenide substrates are also compatible under mild reaction conditions, yielding up to 99%. Notable features of this reaction include its metal‐ and solvent‐free, wide substrate scope and good functional group tolerance. Preliminary mechanistic investigations suggest that a radical pathway is likely involved in this C‒H chalcogenation reaction","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142216970","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}
Twelve thiazole hybrids (2a‐2l) were synthesized in this study incorporating with Schiff base and carbazole scaffolds and characterized by spectral analyses. Antimicrobial activity and antioxidant potency were investigated by agar disc diffusion method and DPPH free radical scavenging assays where trimethyldihydrothiazole 2c had revealed its higher efficacy in both biological studies. It had displayed IC50 of 25.55 ± 0.40 µg/mL which is higher than the standard ascorbic acid (IC50 = 41.31 ± 1.83 µg/mL) as well as dihydrothiazoylchromenone 2e showed promising antioxidant activity with IC50 value of 40.82 ± 0.54. The compound 2c satisfied all the ADME properties and toxicological parameters with maximum drug score value (0.39) among all derivatives. Molecular docking was undertaken for higher bioactive compounds where 2c revealed its wide range of interactions with different amino acid residues which was also endorsed with the output of molecular dynamics simulation.
{"title":"Synthesis, antimicrobial and antioxidant activity with in silico ADMET prediction, molecular docking and dynamics studies of carbazole ring containing thiazole Schiff bases","authors":"Sumita Saznin Marufa, Mohammad Mostafizur Rahman, Md. Mizanur Rahman, Rownok Jahan, Gulshan Ara, Hiroshi Nishino, Mohammad Sayed Alam, Md. Aminul Haque","doi":"10.1002/ajoc.202400363","DOIUrl":"https://doi.org/10.1002/ajoc.202400363","url":null,"abstract":"Twelve thiazole hybrids (2a‐2l) were synthesized in this study incorporating with Schiff base and carbazole scaffolds and characterized by spectral analyses. Antimicrobial activity and antioxidant potency were investigated by agar disc diffusion method and DPPH free radical scavenging assays where trimethyldihydrothiazole 2c had revealed its higher efficacy in both biological studies. It had displayed IC50 of 25.55 ± 0.40 µg/mL which is higher than the standard ascorbic acid (IC50 = 41.31 ± 1.83 µg/mL) as well as dihydrothiazoylchromenone 2e showed promising antioxidant activity with IC50 value of 40.82 ± 0.54. The compound 2c satisfied all the ADME properties and toxicological parameters with maximum drug score value (0.39) among all derivatives. Molecular docking was undertaken for higher bioactive compounds where 2c revealed its wide range of interactions with different amino acid residues which was also endorsed with the output of molecular dynamics simulation.","PeriodicalId":130,"journal":{"name":"Asian Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142217008","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}
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