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  • Biocatalytic site- and enantioselective oxidative dearomatization of phenols
    Nat. Chem. (IF 25.87) Pub Date : 
    Summer A. Baker Dockrey, April L. Lukowski, Marc R. Becker, Alison R. H. Narayan

    Biocatalytic site- and enantioselective oxidative dearomatization of phenols Biocatalytic site- and enantioselective oxidative dearomatization of phenols, Published online: 13 November 2017; doi:10.1038/nchem.2879 NatureArticleSnippet(type=short-summary, markup= Within natural product biosynthetic pathways, nature has evolved highly selective catalysts capable of complexity generating reactions. Leveraging these tools, a suite of catalysts with complementary site- and stereoselectivity have been applied to the oxidative dearomatization of phenolic compounds, enabling one-pot transformations of phenols into various natural products. , isJats=true)

    更新日期:2017-11-13
  • Biocatalytic site- and enantioselective oxidative dearomatization of phenols
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-13
    Summer A. Baker Dockrey, April L. Lukowski, Marc R. Becker, Alison R. H. Narayan

    Biocatalytic site- and enantioselective oxidative dearomatization of phenols Biocatalytic site- and enantioselective oxidative dearomatization of phenols, Published online: 13 November 2017; doi:10.1038/nchem.2879 NatureArticleSnippet(type=short-summary, markup= Within natural product biosynthetic pathways, nature has evolved highly selective catalysts capable of complexity generating reactions. Leveraging these tools, a suite of catalysts with complementary site- and stereoselectivity have been applied to the oxidative dearomatization of phenolic compounds, enabling one-pot transformations of phenols into various natural products. , isJats=true)

    更新日期:2017-11-13
  • Programmable autonomous synthesis of single-stranded DNA
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Jocelyn Y. Kishi, Thomas E. Schaus, Nikhil Gopalkrishnan, Feng Xuan, Peng Yin

    Programmable autonomous synthesis of single-stranded DNAProgrammable autonomous synthesis of single-stranded DNA, Published online: 06 November 2017; doi:10.1038/nchem.2872NatureArticleSnippet(type=short-summary, markup=Primer exchange reaction (PER) cascades have now been used to grow nascent single-stranded DNA with user-specified sequences following prescribed reaction pathways. PER synthesis occurs in a programmable, autonomous, in situ and environmentally responsive fashion, providing a platform for engineering molecular circuits and devices with a wide range of sensing, monitoring, recording, signal processing and actuation capabilities., isJats=true)

    更新日期:2017-11-06
  • Phosphorylation, oligomerization and self-assembly in water under potential prebiotic conditions
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Clémentine Gibard, Subhendu Bhowmik, Megha Karki, Eun-Kyong Kim, Ramanarayanan Krishnamurthy

    Phosphorylation, oligomerization and self-assembly in water under potential prebiotic conditionsPhosphorylation, oligomerization and self-assembly in water under potential prebiotic conditions, Published online: 06 November 2017; doi:10.1038/nchem.2878NatureArticleSnippet(type=short-summary, markup=Phosphorylation of (pre)biological molecules in water has been a long-sought goal in prebiotic chemistry. Now, it has been demonstrated that diamidophosphate phosphorylates nucleosides, amino acids and glycerol/fatty acids in aqueous medium, while simultaneously leading to higher-order structures such as oligonucleotides, peptides and liposomes in the same reaction mixture., isJats=true)

    更新日期:2017-11-06
  • Direct α-C–H bond functionalization of unprotected cyclic amines
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Weijie Chen, Longle Ma, Anirudra Paul, Daniel Seidel

    Direct α-C–H bond functionalization of unprotected cyclic aminesDirect α-C–H bond functionalization of unprotected cyclic amines, Published online: 06 November 2017; doi:10.1038/nchem.2871NatureArticleSnippet(type=short-summary, markup=Cyclic amines bearing α-substituents are valuable building blocks for drug discovery and natural product synthesis. Introduction of α-substituents via site-selective replacement of C–H bonds is highly attractive but typically limited to protected amine substrates. Now, an operationally simple hydride-transfer-based approach enables the introduction of α-substituents on unprotected amines., isJats=true)

    更新日期:2017-11-06
  • Predicting DNA hybridization kinetics from sequence
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Jinny X. Zhang, John Z. Fang, Wei Duan, Lucia R. Wu, Angela W. Zhang, Neil Dalchau, Boyan Yordanov, Rasmus Petersen, Andrew Phillips, David Yu Zhang

    Predicting DNA hybridization kinetics from sequencePredicting DNA hybridization kinetics from sequence, Published online: 06 November 2017; doi:10.1038/nchem.2877NatureArticleSnippet(type=short-summary, markup=The rate constant of DNA hybridization varies over several orders of magnitude and is affected by temperature and DNA sequence. A machine-learning algorithm that is capable of accurately predicting hybridization rate constants has now been developed. Tests with this algorithm showed that over 90% of predictions were correct to within a factor of three., isJats=true)

    更新日期:2017-11-06
  • Programmable autonomous synthesis of single-stranded DNA
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Jocelyn Y. Kishi, Thomas E. Schaus, Nikhil Gopalkrishnan, Feng Xuan, Peng Yin

    Programmable autonomous synthesis of single-stranded DNAProgrammable autonomous synthesis of single-stranded DNA, Published online: 06 November 2017; doi:10.1038/nchem.2872NatureArticleSnippet(type=short-summary, markup=Primer exchange reaction (PER) cascades have now been used to grow nascent single-stranded DNA with user-specified sequences following prescribed reaction pathways. PER synthesis occurs in a programmable, autonomous, in situ and environmentally responsive fashion, providing a platform for engineering molecular circuits and devices with a wide range of sensing, monitoring, recording, signal processing and actuation capabilities., isJats=true)

    更新日期:2017-11-06
  • Phosphorylation, oligomerization and self-assembly in water under potential prebiotic conditions
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Clémentine Gibard, Subhendu Bhowmik, Megha Karki, Eun-Kyong Kim, Ramanarayanan Krishnamurthy

    Phosphorylation, oligomerization and self-assembly in water under potential prebiotic conditionsPhosphorylation, oligomerization and self-assembly in water under potential prebiotic conditions, Published online: 06 November 2017; doi:10.1038/nchem.2878NatureArticleSnippet(type=short-summary, markup=Phosphorylation of (pre)biological molecules in water has been a long-sought goal in prebiotic chemistry. Now, it has been demonstrated that diamidophosphate phosphorylates nucleosides, amino acids and glycerol/fatty acids in aqueous medium, while simultaneously leading to higher-order structures such as oligonucleotides, peptides and liposomes in the same reaction mixture., isJats=true)

    更新日期:2017-11-06
  • Direct α-C–H bond functionalization of unprotected cyclic amines
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Weijie Chen, Longle Ma, Anirudra Paul, Daniel Seidel

    Direct α-C–H bond functionalization of unprotected cyclic aminesDirect α-C–H bond functionalization of unprotected cyclic amines, Published online: 06 November 2017; doi:10.1038/nchem.2871NatureArticleSnippet(type=short-summary, markup=Cyclic amines bearing α-substituents are valuable building blocks for drug discovery and natural product synthesis. Introduction of α-substituents via site-selective replacement of C–H bonds is highly attractive but typically limited to protected amine substrates. Now, an operationally simple hydride-transfer-based approach enables the introduction of α-substituents on unprotected amines., isJats=true)

    更新日期:2017-11-06
  • Predicting DNA hybridization kinetics from sequence
    Nat. Chem. (IF 25.87) Pub Date : 2017-11-06
    Jinny X. Zhang, John Z. Fang, Wei Duan, Lucia R. Wu, Angela W. Zhang, Neil Dalchau, Boyan Yordanov, Rasmus Petersen, Andrew Phillips, David Yu Zhang

    Predicting DNA hybridization kinetics from sequencePredicting DNA hybridization kinetics from sequence, Published online: 06 November 2017; doi:10.1038/nchem.2877NatureArticleSnippet(type=short-summary, markup=The rate constant of DNA hybridization varies over several orders of magnitude and is affected by temperature and DNA sequence. A machine-learning algorithm that is capable of accurately predicting hybridization rate constants has now been developed. Tests with this algorithm showed that over 90% of predictions were correct to within a factor of three., isJats=true)

    更新日期:2017-11-06
  • Polyoxometalate electrocatalysts based on earth-abundant metals for efficient water oxidation in acidic media
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-30
    Marta Blasco-Ahicart, Joaquín Soriano-López, Jorge J. Carbó, Josep M. Poblet, J. R. Galan-Mascaros

    Polyoxometalate electrocatalysts based on earth-abundant metals for efficient water oxidation in acidic media Nature Chemistry, Published online: 30 October 2017; doi:10.1038/nchem.2874 Electrochemical water oxidation in acidic media is a promising water-splitting technique, but typically requires noble metal catalysts. Now, two polyoxometalate salts based on earth-abundant metals have shown excellent catalytic performance for the oxygen evolution reaction. The barium salt of a cobalt- phosphotungstate polyanion outperformed the state-of-the-art IrO2 catalyst at pH's lower than 1.

    更新日期:2017-10-30
  • The changing culture of chemistry
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Bruce C. Gibb

    The changing culture of chemistry Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2881 We all appreciate how chemical knowledge has advanced over the years, but Bruce C. Gibb reminds us that chemical culture has similarly made great advances.

    更新日期:2017-10-24
  • Self-assembly: Supramolecular basketry
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Yi Liu

    Self-assembly: Supramolecular basketry Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2883 Both the topology and the mechanical strength of woven materials have inspired great synthetic efforts to replicate their structures at the nanoscale. Now, a triaxial weave has been prepared by self-assembly of a judiciously designed organic molecule through π–π and CH–π interactions.

    更新日期:2017-10-24
  • Gas-phase chemical kinetics: Three is the magic number
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Rex T. Skodje

    Gas-phase chemical kinetics: Three is the magic number Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2880 Although predicted many years ago, chemically reactive termolecular reactions were thought to be unimportant in defining the behaviour of combustion systems. Now, calculations have shown that such reactions between radicals and long-lived bimolecular complexes can actually play an important role in hydrogen combustion.

    更新日期:2017-10-24
  • Nihonium the obscure
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Iulia Georgescu

    Nihonium the obscure Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2882 Iulia Georgescu explains her fascination with the elusive element 113.

    更新日期:2017-10-24
  • Epigenetics: Making your mark on DNA
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Bryan T. Harada, Chuan He

    Epigenetics: Making your mark on DNA Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2884 Understanding the biological roles of modifications to DNA, RNA and proteins is critical to revealing how cells regulate gene expression in development and disease. Two papers now present a combination of new tools and discoveries that could enable biologists and chemical biologists to better study epigenetic regulation in mammals.

    更新日期:2017-10-24
  • Self-assembly of polyhedral metal–organic framework particles into three-dimensional ordered superstructures
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-23
    Civan Avci, Inhar Imaz, Arnau Carné-Sánchez, Jose Angel Pariente, Nikos Tasios, Javier Pérez-Carvajal, Maria Isabel Alonso, Alvaro Blanco, Marjolein Dijkstra, Cefe López, Daniel Maspoch

    Self-assembly of polyhedral metal–organic framework particles into three-dimensional ordered superstructures Nature Chemistry, Published online: 23 October 2017; doi:10.1038/nchem.2875 Colloidal particles of metal–organic frameworks (ZIF-8 and UiO-66) with different polyhedral shapes can self-assemble into well-ordered, porous three-dimensional superstructures. These superstructures function as photonic crystals, with a photonic band gap that depends on the size of the MOF particles and shifts upon the sorption of guests within their pores.

    更新日期:2017-10-24
  • The changing culture of chemistry
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Bruce C. Gibb

    The changing culture of chemistry Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2881 We all appreciate how chemical knowledge has advanced over the years, but Bruce C. Gibb reminds us that chemical culture has similarly made great advances.

    更新日期:2017-10-24
  • Self-assembly: Supramolecular basketry
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Yi Liu

    Self-assembly: Supramolecular basketry Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2883 Both the topology and the mechanical strength of woven materials have inspired great synthetic efforts to replicate their structures at the nanoscale. Now, a triaxial weave has been prepared by self-assembly of a judiciously designed organic molecule through π–π and CH–π interactions.

    更新日期:2017-10-24
  • Gas-phase chemical kinetics: Three is the magic number
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Rex T. Skodje

    Gas-phase chemical kinetics: Three is the magic number Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2880 Although predicted many years ago, chemically reactive termolecular reactions were thought to be unimportant in defining the behaviour of combustion systems. Now, calculations have shown that such reactions between radicals and long-lived bimolecular complexes can actually play an important role in hydrogen combustion.

    更新日期:2017-10-24
  • Nihonium the obscure
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Iulia Georgescu

    Nihonium the obscure Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2882 Iulia Georgescu explains her fascination with the elusive element 113.

    更新日期:2017-10-24
  • Epigenetics: Making your mark on DNA
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-24
    Bryan T. Harada, Chuan He

    Epigenetics: Making your mark on DNA Nature Chemistry, Published online: 24 October 2017; doi:10.1038/nchem.2884 Understanding the biological roles of modifications to DNA, RNA and proteins is critical to revealing how cells regulate gene expression in development and disease. Two papers now present a combination of new tools and discoveries that could enable biologists and chemical biologists to better study epigenetic regulation in mammals.

    更新日期:2017-10-24
  • Self-assembly of polyhedral metal–organic framework particles into three-dimensional ordered superstructures
    Nat. Chem. (IF 25.87) Pub Date : 2017-10-23
    Civan Avci, Inhar Imaz, Arnau Carné-Sánchez, Jose Angel Pariente, Nikos Tasios, Javier Pérez-Carvajal, Maria Isabel Alonso, Alvaro Blanco, Marjolein Dijkstra, Cefe López, Daniel Maspoch

    Self-assembly of polyhedral metal–organic framework particles into three-dimensional ordered superstructures Nature Chemistry, Published online: 23 October 2017; doi:10.1038/nchem.2875 Colloidal particles of metal–organic frameworks (ZIF-8 and UiO-66) with different polyhedral shapes can self-assemble into well-ordered, porous three-dimensional superstructures. These superstructures function as photonic crystals, with a photonic band gap that depends on the size of the MOF particles and shifts upon the sorption of guests within their pores.

    更新日期:2017-10-24
  • Fluorescent nucleobases as tools for studying DNA and RNA
    Nat. Chem. (IF 25.87) Pub Date : 
    Wang Xu, Ke Min Chan, Eric T. Kool

    Understanding the diversity of dynamic structures and functions of DNA and RNA in biology requires tools that can selectively and intimately probe these biomolecules. Synthetic fluorescent nucleobases that can be incorporated into nucleic acids alongside their natural counterparts have emerged as a powerful class of molecular reporters of location and environment. They are enabling new basic insights into DNA and RNA, and are facilitating a broad range of new technologies with chemical, biological and biomedical applications. In this Review, we will present a brief history of the development of fluorescent nucleobases and explore their utility as tools for addressing questions in biophysics, biochemistry and biology of nucleic acids. We provide chemical insights into the two main classes of these compounds: canonical and non-canonical nucleobases. A point-by-point discussion of the advantages and disadvantages of both types of fluorescent nucleobases is made, along with a perspective into the future challenges and outlook for this burgeoning field.

    更新日期:2017-10-16
  • Oxidase catalysis via aerobically generated hypervalent iodine intermediates
    Nat. Chem. (IF 25.87) Pub Date : 
    Asim Maity, Sung-Min Hyun, David C. Powers

    The development of sustainable oxidation chemistry demands strategies to harness O2 as a terminal oxidant. Oxidase catalysis, in which O2 serves as a chemical oxidant without necessitating incorporation of oxygen into reaction products, would allow diverse substrate functionalization chemistry to be coupled to O2 reduction. Direct O2 utilization suffers from intrinsic challenges imposed by the triplet ground state of O2 and the disparate electron inventories of four-electron O2 reduction and two-electron substrate oxidation. Here, we generate hypervalent iodine reagents—a broadly useful class of selective two-electron oxidants—from O2. This is achieved by intercepting reactive intermediates of aldehyde autoxidation to aerobically generate hypervalent iodine reagents for a broad array of substrate oxidation reactions. The use of aryl iodides as mediators of aerobic oxidation underpins an oxidase catalysis platform that couples substrate oxidation directly to O2 reduction. We anticipate that aerobically generated hypervalent iodine reagents will expand the scope of aerobic oxidation chemistry in chemical synthesis.

    更新日期:2017-10-16
  • Fluorescent nucleobases as tools for studying DNA and RNA
    Nat. Chem. (IF 25.87) Pub Date : 
    Wang Xu, Ke Min Chan, Eric T. Kool

    Fluorescent nucleobases as tools for studying DNA and RNA Nature Chemistry, Published online: 16 October 2017; doi:10.1038/nchem.2859 The emergence of synthetic fluorescent nucleobases that can be incorporated into DNA and RNA in place of their natural counterparts has enabled new tools and technologies with applications in chemistry, biology and biomedicine. This Review discusses chemical insights into canonical and non-canonical nucleobase designs, relating structure to properties.

    更新日期:2017-10-16
  • Oxidase catalysis via aerobically generated hypervalent iodine intermediates
    Nat. Chem. (IF 25.87) Pub Date : 
    Asim Maity, Sung-Min Hyun, David C. Powers

    The development of sustainable oxidation chemistry demands strategies to harness O2 as a terminal oxidant. Oxidase catalysis, in which O2 serves as a chemical oxidant without necessitating incorporation of oxygen into reaction products, would allow diverse substrate functionalization chemistry to be coupled to O2 reduction. Direct O2 utilization suffers from intrinsic challenges imposed by the triplet ground state of O2 and the disparate electron inventories of four-electron O2 reduction and two-electron substrate oxidation. Here, we generate hypervalent iodine reagents—a broadly useful class of selective two-electron oxidants—from O2. This is achieved by intercepting reactive intermediates of aldehyde autoxidation to aerobically generate hypervalent iodine reagents for a broad array of substrate oxidation reactions. The use of aryl iodides as mediators of aerobic oxidation underpins an oxidase catalysis platform that couples substrate oxidation directly to O2 reduction. We anticipate that aerobically generated hypervalent iodine reagents will expand the scope of aerobic oxidation chemistry in chemical synthesis.

    更新日期:2017-10-16
  • Organocatalytic asymmetric arylation of indoles enabled by azo groups
    Nat. Chem. (IF 25.87) Pub Date : 
    Liang-Wen Qi, Jian-Hui Mao, Jian Zhang, Bin Tan

    Arylation is a fundamental reaction that can be mostly fulfilled by electrophilic aromatic substitution and transition-metal-catalysed aryl functionalization. Although the azo group has been used as a directing group for many transformations via transition-metal-catalysed aryl carbon–hydrogen (C–H) bond activation, there remain significant unmet challenges in organocatalytic arylation. Here, we show that the azo group can effectively act as both a directing and activating group for organocatalytic asymmetric arylation of indoles via formal nucleophilic aromatic substitution of azobenzene derivatives. Thus, a wide range of axially chiral arylindoles have been achieved in good yields with excellent enantioselectivities by utilizing chiral phosphoric acid as catalyst. Furthermore, highly enantioenriched pyrroloindoles bearing two contiguous quaternary chiral centres have also been obtained via a cascade enantioselective formal nucleophilic aromatic substitution–cyclization process. This strategy should be useful in other related research fields and will open new avenues for organocatalytic asymmetric aryl functionalization.

    更新日期:2017-10-11
  • Mechanism-based enhancement of scope and enantioselectivity for reactions involving a copper-substituted stereogenic carbon centre
    Nat. Chem. (IF 25.87) Pub Date : 
    Jaehee Lee, Suttipol Radomkit, Sebastian Torker, Juan del Pozo, Amir H. Hoveyda

    A rapidly emerging set of catalytic reactions involves intermediates that contain a copper-substituted stereogenic carbon centre. Here, we demonstrate that an intimate understanding of this distinction provides ways for addressing limitations in reaction scope and explaining why unexpected variations in enantioselectivity often occur. By using catalytic enantioselective Cu–boryl addition to alkenes as the model process, we elucidate several key mechanistic principles. We show that higher electrophile concentration can lead to elevated enantioselectivity. This is because diastereoselective Cu–H elimination may be avoided and/or achiral Cu–boryl intermediates can be converted to allyl–B(pin) rather than add to an alkene. We illustrate that lower alkene amounts and/or higher chiral ligand concentration can minimize the deleterious influence of achiral Cu–alkyl species, resulting in improved enantiomeric ratios. Moreover, and surprisingly, we find that enantioselectivities are higher with the less reactive allylphenyl carbonates as chemoselective copper–hydride elimination is faster with an achiral Cu-alkyl species.

    更新日期:2017-10-11
  • Organocatalytic asymmetric arylation of indoles enabled by azo groups
    Nat. Chem. (IF 25.87) Pub Date : 
    Liang-Wen Qi, Jian-Hui Mao, Jian Zhang, Bin Tan

    Arylation is a fundamental reaction that can be mostly fulfilled by electrophilic aromatic substitution and transition-metal-catalysed aryl functionalization. Although the azo group has been used as a directing group for many transformations via transition-metal-catalysed aryl carbon–hydrogen (C–H) bond activation, there remain significant unmet challenges in organocatalytic arylation. Here, we show that the azo group can effectively act as both a directing and activating group for organocatalytic asymmetric arylation of indoles via formal nucleophilic aromatic substitution of azobenzene derivatives. Thus, a wide range of axially chiral arylindoles have been achieved in good yields with excellent enantioselectivities by utilizing chiral phosphoric acid as catalyst. Furthermore, highly enantioenriched pyrroloindoles bearing two contiguous quaternary chiral centres have also been obtained via a cascade enantioselective formal nucleophilic aromatic substitution–cyclization process. This strategy should be useful in other related research fields and will open new avenues for organocatalytic asymmetric aryl functionalization.

    更新日期:2017-10-11
  • Mechanism-based enhancement of scope and enantioselectivity for reactions involving a copper-substituted stereogenic carbon centre
    Nat. Chem. (IF 25.87) Pub Date : 
    Jaehee Lee, Suttipol Radomkit, Sebastian Torker, Juan del Pozo, Amir H. Hoveyda

    A rapidly emerging set of catalytic reactions involves intermediates that contain a copper-substituted stereogenic carbon centre. Here, we demonstrate that an intimate understanding of this distinction provides ways for addressing limitations in reaction scope and explaining why unexpected variations in enantioselectivity often occur. By using catalytic enantioselective Cu–boryl addition to alkenes as the model process, we elucidate several key mechanistic principles. We show that higher electrophile concentration can lead to elevated enantioselectivity. This is because diastereoselective Cu–H elimination may be avoided and/or achiral Cu–boryl intermediates can be converted to allyl–B(pin) rather than add to an alkene. We illustrate that lower alkene amounts and/or higher chiral ligand concentration can minimize the deleterious influence of achiral Cu–alkyl species, resulting in improved enantiomeric ratios. Moreover, and surprisingly, we find that enantioselectivities are higher with the less reactive allylphenyl carbonates as chemoselective copper–hydride elimination is faster with an achiral Cu-alkyl species.

    更新日期:2017-10-11
  • The darmstadtium cornerstone
    Nat. Chem. (IF 25.87) Pub Date : 
    Dieter Ackermann

    Dieter Ackermann explains why element 110 occupies a significant place in the superheavy corner of the periodic table.

    更新日期:2017-09-28
  • Synthetic nat- or ent-steroids in as few as five chemical steps from epichlorohydrin
    Nat. Chem. (IF 25.87) Pub Date : 
    Wan Shin Kim, Kang Du, Alan Eastman, Russell P. Hughes, Glenn C. Micalizio

    Today, more than 100 Food and Drug Administration-approved steroidal agents are prescribed daily for indications including heart failure, inflammation, pain and cancer. While triumphs in organic chemistry have enabled the establishment and sustained growth of the steroid pharmaceutical industry, the production of highly functionalized synthetic steroids of varying substitution and stereochemistry remains challenging, despite the numerous reports of elegant strategies for their de novo synthesis. Here, we describe an advance in chemical synthesis that has established an enantiospecific means to access novel steroids with unprecedented facility and flexibility through the sequential use of two powerful ring-forming reactions: a modern metallacycle-mediated annulative cross-coupling and a new acid-catalysed vinylcyclopropane rearrangement cascade. In addition to accessing synthetic steroids of either enantiomeric series, these steroidal products have been selectively functionalized within each of the four carbocyclic rings, a synthetic ent-steroid has been prepared on a multigram scale, the enantiomer of a selective oestrogen has been synthesized, and a novel ent-steroid with growth inhibitory properties in three cancer cell lines has been discovered.

    更新日期:2017-09-26
  • Synthetic nat- or ent-steroids in as few as five chemical steps from epichlorohydrin
    Nat. Chem. (IF 25.87) Pub Date : 
    Wan Shin Kim, Kang Du, Alan Eastman, Russell P. Hughes, Glenn C. Micalizio

    Today, more than 100 Food and Drug Administration-approved steroidal agents are prescribed daily for indications including heart failure, inflammation, pain and cancer. While triumphs in organic chemistry have enabled the establishment and sustained growth of the steroid pharmaceutical industry, the production of highly functionalized synthetic steroids of varying substitution and stereochemistry remains challenging, despite the numerous reports of elegant strategies for their de novo synthesis. Here, we describe an advance in chemical synthesis that has established an enantiospecific means to access novel steroids with unprecedented facility and flexibility through the sequential use of two powerful ring-forming reactions: a modern metallacycle-mediated annulative cross-coupling and a new acid-catalysed vinylcyclopropane rearrangement cascade. In addition to accessing synthetic steroids of either enantiomeric series, these steroidal products have been selectively functionalized within each of the four carbocyclic rings, a synthetic ent-steroid has been prepared on a multigram scale, the enantiomer of a selective oestrogen has been synthesized, and a novel ent-steroid with growth inhibitory properties in three cancer cell lines has been discovered.

    更新日期:2017-09-26
  • Engineering nucleic acid structures for programmable molecular circuitry and intracellular biocomputation
    Nat. Chem. (IF 25.87) Pub Date : 
    Jiang Li, Alexander A. Green, Hao Yan, Chunhai Fan

    Nucleic acids have attracted widespread attention due to the simplicity with which they can be designed to form discrete structures and programmed to perform specific functions at the nanoscale. The advantages of DNA/RNA nanotechnology offer numerous opportunities for in-cell and in-vivo applications, and the technology holds great promise to advance the growing field of synthetic biology. Many elegant examples have revealed the potential in integrating nucleic acid nanostructures in cells and in vivo where they can perform important physiological functions. In this Review, we summarize the current abilities of DNA/RNA nanotechnology to realize applications in live cells and then discuss the key problems that must be solved to fully exploit the useful properties of nanostructures. Finally, we provide viewpoints on how to integrate the tools provided by DNA/RNA nanotechnology and related new technologies to construct nucleic acid nanostructure-based molecular circuitry for synthetic biology.

    更新日期:2017-09-25
  • Engineering nucleic acid structures for programmable molecular circuitry and intracellular biocomputation
    Nat. Chem. (IF 25.87) Pub Date : 
    Jiang Li, Alexander A. Green, Hao Yan, Chunhai Fan

    Nucleic acids have attracted widespread attention due to the simplicity with which they can be designed to form discrete structures and programmed to perform specific functions at the nanoscale. The advantages of DNA/RNA nanotechnology offer numerous opportunities for in-cell and in-vivo applications, and the technology holds great promise to advance the growing field of synthetic biology. Many elegant examples have revealed the potential in integrating nucleic acid nanostructures in cells and in vivo where they can perform important physiological functions. In this Review, we summarize the current abilities of DNA/RNA nanotechnology to realize applications in live cells and then discuss the key problems that must be solved to fully exploit the useful properties of nanostructures. Finally, we provide viewpoints on how to integrate the tools provided by DNA/RNA nanotechnology and related new technologies to construct nucleic acid nanostructure-based molecular circuitry for synthetic biology.

    更新日期:2017-09-25
  • Glucose-responsive insulin by molecular and physical design
    Nat. Chem. (IF 25.87) Pub Date : 
    Naveed A. Bakh, Abel B. Cortinas, Michael A. Weiss, Robert S. Langer, Daniel G. Anderson, Zhen Gu, Sanjoy Dutta, Michael S. Strano

    Glucose-responsive insulin by molecular and physical design Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2857 Glucose-responsive insulin is a therapeutic that modulates its potency, concentration or dosing relative to a patient’s dynamic glucose concentration. This Perspective summarizes some of the recent accomplishments in this field as well as discussing new computational algorithms that may aid in the development of such therapeutics.

    更新日期:2017-09-22
  • Nucleic acid nanomaterials: Silver-wired DNA
    Nat. Chem. (IF 25.87) Pub Date : 
    Pascal Auffinger, Eric Ennifar

    Nucleic acid nanomaterials: Silver-wired DNA Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2869 DNA double helical structures are supramolecular assemblies that are typically held together by classical Watson–Crick pairing. Now, nucleotide chelation of silver ions supports an extended silver–DNA hybrid duplex featuring an uninterrupted silver array.

    更新日期:2017-09-22
  • Synthesis and the Nobel Prize in Chemistry
    Nat. Chem. (IF 25.87) Pub Date : 
    Jeffrey I. Seeman

    Synthesis and the Nobel Prize in Chemistry Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2864 The question often arises as to who may have deserved a Nobel Prize but was not awarded one. Rarely is this discussion extended to who should have received more than one Nobel Prize, but in the field of organic synthesis there are some compelling candidates.

    更新日期:2017-09-22
  • Water dynamics: Gliding and trudging
    Nat. Chem. (IF 25.87) Pub Date : 
    Yoshimitsu Itoh, Takuzo Aida

    Water dynamics: Gliding and trudging Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2870 Water is increasingly recognized as being of paramount importance in biological processes, yet its exact role remains difficult to elucidate. Now, the motion of water molecules within and around a synthetic peptide-amphiphile nanofibre has been precisely determined, showing significant differences between its core and surface.

    更新日期:2017-09-22
  • Reaction dynamics: The view from a transition state
    Nat. Chem. (IF 25.87) Pub Date : 
    Robert E. Continetti

    Reaction dynamics: The view from a transition state Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2868 Ejecting electrons from negative ions using light can create structures that very closely resemble the transition states of bimolecular reactions. Now, using this technique, trapped quantum states, or 'resonances', have been observed in a seven-atom reaction, and theory has been shown to be up to the task of capturing such complex phenomena.

    更新日期:2017-09-22
  • Glucose-responsive insulin by molecular and physical design
    Nat. Chem. (IF 25.87) Pub Date : 
    Naveed A. Bakh, Abel B. Cortinas, Michael A. Weiss, Robert S. Langer, Daniel G. Anderson, Zhen Gu, Sanjoy Dutta, Michael S. Strano

    Glucose-responsive insulin by molecular and physical design Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2857 Glucose-responsive insulin is a therapeutic that modulates its potency, concentration or dosing relative to a patient’s dynamic glucose concentration. This Perspective summarizes some of the recent accomplishments in this field as well as discussing new computational algorithms that may aid in the development of such therapeutics.

    更新日期:2017-09-22
  • The darmstadtium cornerstone
    Nat. Chem. (IF 25.87) Pub Date : 
    Dieter Ackermann

    The darmstadtium cornerstone Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2867 Dieter Ackermann explains why element 110 occupies a significant place in the superheavy corner of the periodic table.

    更新日期:2017-09-22
  • Nucleic acid nanomaterials: Silver-wired DNA
    Nat. Chem. (IF 25.87) Pub Date : 
    Pascal Auffinger, Eric Ennifar

    Nucleic acid nanomaterials: Silver-wired DNA Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2869 DNA double helical structures are supramolecular assemblies that are typically held together by classical Watson–Crick pairing. Now, nucleotide chelation of silver ions supports an extended silver–DNA hybrid duplex featuring an uninterrupted silver array.

    更新日期:2017-09-22
  • Synthesis and the Nobel Prize in Chemistry
    Nat. Chem. (IF 25.87) Pub Date : 
    Jeffrey I. Seeman

    Synthesis and the Nobel Prize in Chemistry Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2864 The question often arises as to who may have deserved a Nobel Prize but was not awarded one. Rarely is this discussion extended to who should have received more than one Nobel Prize, but in the field of organic synthesis there are some compelling candidates.

    更新日期:2017-09-22
  • Water dynamics: Gliding and trudging
    Nat. Chem. (IF 25.87) Pub Date : 
    Yoshimitsu Itoh, Takuzo Aida

    Water dynamics: Gliding and trudging Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2870 Water is increasingly recognized as being of paramount importance in biological processes, yet its exact role remains difficult to elucidate. Now, the motion of water molecules within and around a synthetic peptide-amphiphile nanofibre has been precisely determined, showing significant differences between its core and surface.

    更新日期:2017-09-22
  • Reaction dynamics: The view from a transition state
    Nat. Chem. (IF 25.87) Pub Date : 
    Robert E. Continetti

    Reaction dynamics: The view from a transition state Nature Chemistry, Published online: 22 September 2017; doi:10.1038/nchem.2868 Ejecting electrons from negative ions using light can create structures that very closely resemble the transition states of bimolecular reactions. Now, using this technique, trapped quantum states, or 'resonances', have been observed in a seven-atom reaction, and theory has been shown to be up to the task of capturing such complex phenomena.

    更新日期:2017-09-22
  • Bioinspired chemical synthesis of monomeric and dimeric stephacidin A congeners
    Nat. Chem. (IF 25.87) Pub Date : 
    Ken Mukai, Danilo Pereira de Sant'Ana, Yasuo Hirooka, Eduardo V. Mercado-Marin, David E. Stephens, Kevin G. M. Kou, Sven C. Richter, Naomi Kelley, Richmond Sarpong

    Stephacidin A and its congeners are a collection of secondary metabolites that possess intriguing structural motifs. They stem from unusual biosynthetic sequences that lead to the incorporation of a prenyl or reverse-prenyl group into a bicyclo[2.2.2]diazaoctane framework, a chromene unit or the vestige thereof. To complement biosynthetic studies, which normally play a significant role in unveiling the biosynthetic pathways of natural products, here we demonstrate that chemical synthesis can provide important insights into biosynthesis. We identify a short total synthesis of congeners in the reverse-prenylated indole alkaloid family related to stephacidin A by taking advantage of a direct indole C6 halogenation of the related ketopremalbrancheamide. This novel strategic approach has now made possible the syntheses of several natural products, including malbrancheamides B and C, notoamides F, I and R, aspergamide B, and waikialoid A, which is a heterodimer of avrainvillamide and aspergamide B. Our approach to the preparation of these prenylated and reverse-prenylated indole alkaloids is bioinspired, and may also inform the as-yet undetermined biosynthesis of several congeners.

    更新日期:2017-09-20
  • Bioinspired chemical synthesis of monomeric and dimeric stephacidin A congeners
    Nat. Chem. (IF 25.87) Pub Date : 2017-09-18
    Ken Mukai, Danilo Pereira de Sant'Ana, Yasuo Hirooka, Eduardo V. Mercado-Marin, David E. Stephens, Kevin G. M. Kou, Sven C. Richter, Naomi Kelley, Richmond Sarpong
    更新日期:2017-09-20
  • Late-stage chemoselective functional-group manipulation of bioactive natural products with super-electrophilic silylium ions
    Nat. Chem. (IF 25.87) Pub Date : 2017-09-18
    Trandon A. Bender, Philippa R. Payne, Michel R. Gagné
    更新日期:2017-09-18
  • Designing cooperatively folded abiotic uni- and multimolecular helix bundles
    Nat. Chem. (IF 25.87) Pub Date : 2017-09-18
    Soumen De, Bo Chi, Thierry Granier, Ting Qi, Victor Maurizot, Ivan Huc
    更新日期:2017-09-18
  • Late-stage chemoselective functional-group manipulation of bioactive natural products with super-electrophilic silylium ions
    Nat. Chem. (IF 25.87) Pub Date : 
    Trandon A. Bender, Philippa R. Payne, Michel R. Gagné

    Late-stage chemoselective functional-group manipulation of bioactive natural products with super-electrophilic silylium ions Nature Chemistry, Published online: 18 September 2017; doi:10.1038/nchem.2863 Determining the structure­–activity relationships for complex structures can be quite challenging, but it is often the method in which many natural products can be used as drugs. Now, the combination of a fluoroaryl borane catalyst, a phosphine additive and a silane reducing agent enables the late-stage selective modification of complex bioactive natural products.

    更新日期:2017-09-18
  • Designing cooperatively folded abiotic uni- and multimolecular helix bundles
    Nat. Chem. (IF 25.87) Pub Date : 
    Soumen De, Bo Chi, Thierry Granier, Ting Qi, Victor Maurizot, Ivan Huc

    Designing cooperatively folded abiotic uni- and multimolecular helix bundles Nature Chemistry, Published online: 18 September 2017; doi:10.1038/nchem.2854 Rationally designed arrays of hydrogen bonds between aromatic oligoamide segments have now been shown to generate abiotic helix-turn-helix and unexpected dimeric and trimeric helix bundle motifs. These structures show kinetic and thermodynamic stability, and cooperative folding in nonpolar solvents.

    更新日期:2017-09-18
  • Chromophore twisting in the excited state of a photoswitchable fluorescent protein captured by time-resolved serial femtosecond crystallography
    Nat. Chem. (IF 25.87) Pub Date : 
    Nicolas Coquelle, Michel Sliwa, Joyce Woodhouse, Giorgio Schirò, Virgile Adam, Andrew Aquila, Thomas R. M. Barends, Sébastien Boutet, Martin Byrdin, Sergio Carbajo, Eugenio De la Mora, R. Bruce Doak, Mikolaj Feliks, Franck Fieschi, Lutz Foucar, Virginia Guillon, Mario Hilpert, Mark S. Hunter, Stefan Jakobs, Jason E. Koglin, Gabriela Kovacsova, Thomas J. Lane, Bernard Lévy, Mengning Liang, Karol Nass, Jacqueline Ridard, Joseph S. Robinson, Christopher M. Roome, Cyril Ruckebusch, Matthew Seaberg, Michel Thepaut, Marco Cammarata, Isabelle Demachy, Martin Field, Robert L. Shoeman, Dominique Bourgeois, Jacques-Philippe Colletier, Ilme Schlichting, Martin Weik

    Chromophores absorb light in photosensitive proteins and thereby initiate fundamental biological processes such as photosynthesis, vision and biofluorescence. An important goal in their understanding is the provision of detailed structural descriptions of the ultrafast photochemical events that they undergo, in particular of the excited states that connect chemistry to biological function. Here we report on the structures of two excited states in the reversibly photoswitchable fluorescent protein rsEGFP2. We populated the states through femtosecond illumination of rsEGFP2 in its non-fluorescent off state and observed their build-up (within less than one picosecond) and decay (on the several picosecond timescale). Using an X-ray free-electron laser, we performed picosecond time-resolved crystallography and show that the hydroxybenzylidene imidazolinone chromophore in one of the excited states assumes a near-canonical twisted configuration halfway between the trans and cis isomers. This is in line with excited-state quantum mechanics/molecular mechanics and classical molecular dynamics simulations. Our new understanding of the structure around the twisted chromophore enabled the design of a mutant that displays a twofold increase in its off-to-on photoswitching quantum yield.

    更新日期:2017-09-12
  • Assembly of a biocompatible triazole-linked gene by one-pot click-DNA ligation
    Nat. Chem. (IF 25.87) Pub Date : 
    Mikiembo Kukwikila, Nittaya Gale, Afaf H. El-Sagheer, Tom Brown, Ali Tavassoli

    The chemical synthesis of oligonucleotides and their enzyme-mediated assembly into genes and genomes has significantly advanced multiple scientific disciplines. However, these approaches are not without their shortcomings; enzymatic amplification and ligation of oligonucleotides into genes and genomes makes automation challenging, and site-specific incorporation of epigenetic information and/or modified bases into large constructs is not feasible. Here we present a fully chemical one-pot method for the assembly of oligonucleotides into a gene by click-DNA ligation. We synthesize the 335 base-pair gene that encodes the green fluorescent protein iLOV from ten functionalized oligonucleotides that contain 5ʹ-azide and 3ʹ-alkyne units. The resulting click-linked iLOV gene contains eight triazoles at the sites of chemical ligation, and yet is fully biocompatible; it is replicated by DNA polymerases in vitro and encodes a functional iLOV protein in Escherichia coli. We demonstrate the power and potential of our one-pot gene-assembly method by preparing an epigenetically modified variant of the iLOV gene.

    更新日期:2017-09-12
  • Direct mapping of the angle-dependent barrier to reaction for Cl + CHD3 using polarized scattering data
    Nat. Chem. (IF 25.87) Pub Date : 
    Huilin Pan, Fengyan Wang, Gábor Czakó, Kopin Liu

    The transition state, which gates and modulates reactive flux, serves as the central concept in our understanding of activated reactions. The barrier height of the transition state can be estimated from the activation energy taken from thermal kinetics data or from the energetic threshold in the measured excitation function (the dependence of reaction cross-sections on initial collision energies). However, another critical and equally important property, the angle-dependent barrier to reaction, has not yet been amenable to experimental determination until now. Here, using the benchmark reaction of Cl + CHD3(v1 = 1) as an example, we show how to map this anisotropic property of the transition state as a function of collision energy from the preferred reactant bond alignment of the backward-scattered products—the imprints of small impact-parameter collisions. The deduced bend potential at the transition state agrees with ab initio calculations. We expect that the method should be applicable to many other direct reactions with a collinear barrier.

    更新日期:2017-09-12
  • Vibronically coherent ultrafast triplet-pair formation and subsequent thermally activated dissociation control efficient endothermic singlet fission
    Nat. Chem. (IF 25.87) Pub Date : 
    Hannah L. Stern, Alexandre Cheminal, Shane R. Yost, Katharina Broch, Sam L. Bayliss, Kai Chen, Maxim Tabachnyk, Karl Thorley, Neil Greenham, Justin M. Hodgkiss, John Anthony, Martin Head-Gordon, Andrew J. Musser, Akshay Rao, Richard H. Friend

    Singlet exciton fission (SF), the conversion of one spin-singlet exciton (S1) into two spin-triplet excitons (T1), could provide a means to overcome the Shockley–Queisser limit in photovoltaics. SF as measured by the decay of S1 has been shown to occur efficiently and independently of temperature, even when the energy of S1 is as much as 200 meV less than that of 2T1. Here we study films of triisopropylsilyltetracene using transient optical spectroscopy and show that the triplet pair state (TT), which has been proposed to mediate singlet fission, forms on ultrafast timescales (in 300 fs) and that its formation is mediated by the strong coupling of electronic and vibrational degrees of freedom. This is followed by a slower loss of singlet character as the excitation evolves to become only TT. We observe the TT to be thermally dissociated on 10–100 ns timescales to form free triplets. This provides a model for ‘temperature-independent’ efficient TT formation and thermally activated TT separation.

    更新日期:2017-09-12
  • Chromophore twisting in the excited state of a photoswitchable fluorescent protein captured by time-resolved serial femtosecond crystallography
    Nat. Chem. (IF 25.87) Pub Date : 
    Nicolas Coquelle, Michel Sliwa, Joyce Woodhouse, Giorgio Schirò, Virgile Adam, Andrew Aquila, Thomas R. M. Barends, Sébastien Boutet, Martin Byrdin, Sergio Carbajo, Eugenio De la Mora, R. Bruce Doak, Mikolaj Feliks, Franck Fieschi, Lutz Foucar, Virginia Guillon, Mario Hilpert, Mark S. Hunter, Stefan Jakobs, Jason E. Koglin, Gabriela Kovacsova, Thomas J. Lane, Bernard Lévy, Mengning Liang, Karol Nass, Jacqueline Ridard, Joseph S. Robinson, Christopher M. Roome, Cyril Ruckebusch, Matthew Seaberg, Michel Thepaut, Marco Cammarata, Isabelle Demachy, Martin Field, Robert L. Shoeman, Dominique Bourgeois, Jacques-Philippe Colletier, Ilme Schlichting, Martin Weik
    更新日期:2017-09-12
  • Assembly of a biocompatible triazole-linked gene by one-pot click-DNA ligation
    Nat. Chem. (IF 25.87) Pub Date : 
    Mikiembo Kukwikila, Nittaya Gale, Afaf H. El-Sagheer, Tom Brown, Ali Tavassoli
    更新日期:2017-09-12
  • Vibronically coherent ultrafast triplet-pair formation and subsequent thermally activated dissociation control efficient endothermic singlet fission
    Nat. Chem. (IF 25.87) Pub Date : 
    Hannah L. Stern, Alexandre Cheminal, Shane R. Yost, Katharina Broch, Sam L. Bayliss, Kai Chen, Maxim Tabachnyk, Karl Thorley, Neil Greenham, Justin M. Hodgkiss, John Anthony, Martin Head-Gordon, Andrew J. Musser, Akshay Rao, Richard H. Friend
    更新日期:2017-09-12
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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