Organic & Biomolecular Chemistry Blog

The following Organic & Biomolecular Chemistry articles have all been recommened by the reviewers of the articles as being particularly interesting or particularly significant research. These have all been made free to access until 31st December 2014. The order they appear in the list holds no special meaning or ranking.

Catalytic asymmetric desymmetrization approaches to enantioenriched cyclopentanes
Madhu Sudan Manna and Santanu Mukherjee  
DOI: 10.1039/C4OB01649A, Perspective

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Corrin-based chemosensors for the ASSURED detection of endogenous cyanide
Felix Zelder and Lucas Tivana  
DOI: 10.1039/C4OB01889C, Perspective

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An efficient synthetic route to 1,3-bis(arylethynyl)isobenzofuran using alkoxybenzocyclobutenone as a reactive platform
Kenta Asahina, Suguru Matsuoka, Ryosuke Nakayama and Toshiyuki Hamura  
DOI: 10.1039/C4OB02012J, Communication

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Cationic azacryptands as selective three-way DNA junction binding agents
Jana Novotna, Aurelien Laguerre, Anton Granzhan, Marc Pirrotta, Marie-Paule Teulade-Fichou and David Monchaud  
DOI: 10.1039/C4OB01846J, Paper

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An efficient reagent for covalent introduction of alkynes into proteins
Jie Zhang, Dejun Ma, Dawei Du, Zhen Xi and Long Yi  
DOI: 10.1039/C4OB01873G, Communication

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Efficient merging of copper and photoredox catalysis for the asymmetric cross-dehydrogenative-coupling of alkynes and tetrahydroisoquinolines
Inna Perepichka, Soumen Kundu, Zoë Hearne and Chao-Jun Li  
DOI: 10.1039/C4OB02138J, Paper

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Naphthalene diimides as red fluorescent pH sensors for functional cell imaging
Filippo Doria, Marco Folini, Vincenzo Grande, Graziella Cimino-Reale, Nadia Zaffaroni and Mauro Freccero  
DOI: 10.1039/C4OB02054E, Paper

A recent communication in Organic and Biomolecular Chemistry reports the synthesis of a new reagent for the introduction of alkynes into proteins; a key step for click bioconjugation. The new diazonium reagent was prepared in a one-pot synthesis from commercially available 4-ethynylaniline.

Having optimized bioconjugation in a tyrosine containing small molecule, the new diazonium reagent was then used to covalently label proteins. Fluorescence labelling of protein surface tyrosine residues was achieved under mild conditions (pH 8.0) by reaction of the protein with the diazonium reagent and subsequent reaction with an azide-containing fluorescent compound. The new diazonium reagent was also used to achieve protein PEGylation; a strategy that could be employed to improve protein stability and reduce immunogenicity.

The new diazonium reagent can facilitate bioconjugation in a range of proteins and could be a useful addition to the biochemist’s toolbox.

Read the full article:
An efficient reagent for covalent introduction of alkynes into proteins
Jie Zhang, Dejun Ma, Dawei Du, Zhen Xi and Long Yi
Org. Biomol. Chem., 2014, DOI: 10.1039/C4OB01873G

The following Organic & Biomolecular Chemistry articles have all been recommened by the reviewers of the articles as being particularly interesting or particularly significant research. These have all been made free to access until 30th November. The order they appear in the list holds no special meaning or ranking.

Design strategies for bioorthogonal smart probes
Peyton Shieh and Carolyn R. Bertozzi
DOI: 10.1039/C4OB01632G, Review Article

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Stereoselective intermolecular [2 + 2]-photocycloaddition reactions of maleic anhydride: stereocontrolled and regiocontrolled access to 1,2,3-trifunctionalized cyclobutanes
Florian Hernvann, Gloria Rasore, Valérie Declerck and David J. Aitken
DOI: 10.1039/C4OB01383B, Paper

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Towards novel efficient and stable nuclear import signals: synthesis and properties of trimethylguanosine cap analogs modified within the 5′,5′-triphosphate bridge
Malgorzata Zytek, Joanna Kowalska, Maciej Lukaszewicz, Blazej A. Wojtczak, Joanna Zuberek, Aleksandra Ferenc-Mrozek, Edward Darzynkiewicz, Anna Niedzwiecka and Jacek Jemielity
DOI: 10.1039/C4OB01579G, Paper

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Catalytic asymmetric synthesis of the pentacyclic core of (−)-nakadomarin A via oxazolidine as an iminium cation equivalent
Nobuya Tsuji, Michael Stadler, Naoya Kazumi, Tsubasa Inokuma, Yusuke Kobayashi and Yoshiji Takemoto
DOI: 10.1039/C4OB01678E, Communication

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Short and efficient synthesis of fluorinated δ-lactams
Thomas J. Cogswell, Craig S. Donald, De-Liang Long and Rodolfo Marquez
DOI: 10.1039/C4OB01547A, Paper

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An efficient route to synthesize isatins by metal-free, iodine-catalyzed sequential C(sp3)–H oxidation and intramolecular C–N bond formation of 2′-aminoacetophenones
Venkatachalam Rajeshkumar, Selvaraj Chandrasekar and Govindasamy Sekar
DOI: 10.1039/C4OB01564A, Paper

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5-Nitroindole oligonucleotides with alkynyl side chains: universal base pairing, triple bond hydration and properties of pyrene “click” adducts
Sachin A. Ingale, Peter Leonard, Haozhe Yang and Frank Seela
DOI: 10.1039/C4OB01478B, Paper

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Cross-strand histidine–aromatic interactions enhance acyl-transfer rates in beta-hairpin peptide catalysts
M. Matsumoto, S. J. Lee, M. R. Gagné and M. L. Waters
DOI: 10.1039/C4OB01754D, Paper

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The asymmetric syntheses of pyrrolizidines, indolizidines and quinolizidines via two sequential tandem ring-closure/N-debenzylation processes
Stephen G. Davies, Ai M. Fletcher, Emma M. Foster, Ian T. T. Houlsby, Paul M. Roberts, Thomas M. Schofield and James E. Thomson
DOI: 10.1039/C4OB01737D, Paper

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Organocatalytic Michael addition–lactonisation of carboxylic acids using α,β-unsaturated trichloromethyl ketones as α,β-unsaturated ester equivalents
Louis C. Morrill, Daniel G. Stark, James E. Taylor, Siobhan R. Smith, James A. Squires, Agathe C. A. D’Hollander, Carmen Simal, Peter Shapland, Timothy J. C. O’Riordan and Andrew D. Smith
DOI: 10.1039/C4OB01788A, Paper

The Ugi reaction was one of the very first multicomponent reactions exploited to develop chemical libraries, which further extended to combinatorial, solid phase and flow synthesis for evolving new lead structures of active agents. Implementing the Ugi reaction in combination with other organic reactions enlarges the chemical diversity of possible products.

Researchers at Vrije University Brussel, led by Steven Ballet, have made a step forward by executing a one-pot Ugi-Huisgen tandem reaction and found an alternative high atom economy pathway for the synthesis of conformationally constrained, amino-triazoloazepinone-containing di- and tripeptides.

Strategically, they have used an unconventional azide containing acid, and alkyne amine along with traditional aldehydes and isocyanides. By using equimolar reactants with very mild reaction conditions, they were able to observe total conversion to the linear Ugi-compounds equipped with azide and alkyne functionality. Furthermore, they have cyclised the resulting compounds into the respective triazoles, by performing a catalyst-free Huisgen cycloaddition reaction in a sealed tube.

Variation in substitution patterns and tolerance of a large array of aldehydes in this methodology will open a new avenue for the synthesis of various building blocks to be used in peptidomimetics with a wide range of applications.

Find out more in their Communication:

Efficient synthesis of conformationally constrained, amino-triazoloazepinone-containing di- and tripeptides via a one-pot Ugi–Huisgen tandem reaction
T. M. A. Barlow, M. Jida, D. Tourwéa and S. Ballet
DOI: 10.1039/C4OB01381F

Check out the following HOT articles, as recommened by the reviewers of the articles. These have all been made free to access until 20th October:

Estimating the shape and size of supramolecular assemblies by variable temperature diffusion ordered spectroscopy
Benjamin M. Schulze, Davita L. Watkins, Jing Zhang, Ion Ghiviriga and Ronald K. Castellano
DOI: 10.1039/C4OB01373E, Communication

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Evolution of a strategy for preparing bioactive small molecules by sequential multicomponent assembly processes, cyclizations, and diversification
James J. Sahn, Brett A. Granger and Stephen F. Martin
DOI: 10.1039/C4OB00835A, Review Article
From themed collection In Celebration of Richard Taylor’s 65^th Birthday

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Development and mechanistic studies of an optimized receptor for trimethyllysine using iterative redesign by dynamic combinatorial chemistry
Nicholas K. Pinkin and Marcey L. Waters
DOI: 10.1039/C4OB01249F, Paper

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Modulation of DNA–polyamide interaction by β-alanine substitutions: a study of positional effects on binding affinity, kinetics and thermodynamics
Shuo Wang, Karl Aston, Kevin J. Koeller, G. Davis Harris, Nigam P. Rath, James K. Bashkin and W. David Wilson
DOI: 10.1039/C4OB01456A, Paper

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Iridium-catalyzed C–H borylation of pyridines
Scott A. Sadler, Hazmi Tajuddin, Ibraheem A. I. Mkhalid, Andrei S. Batsanov, David Albesa-Jove, Man Sing Cheung, Aoife C. Maxwell, Lena Shukla, Bryan Roberts, David C. Blakemore, Zhenyang Lin, Todd B. Marder and Patrick G. Steel
DOI: 10.1039/C4OB01565G, Paper

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Efficient synthesis of conformationally constrained, amino-triazoloazepinone-containing di- and tripeptides via a one-pot Ugi–Huisgen tandem reaction
T. M. A. Barlow, M. Jida, D. Tourwé and S. Ballet
DOI: 10.1039/C4OB01381F, Communication

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Influence of B-ring modifications on proton affinity, transmembrane anion transport and anti-cancer properties of synthetic prodigiosenes
Estelle Marchal, Soumya Rastogi, Alison Thompson and Jeffery T. Davis
DOI: 10.1039/C4OB01399A, Paper

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Catalytic amide allylation of α-ketoesters: extremely high enantioselective synthesis of ester functionalised α-methylene-γ-butyrolactones
Masaki Takahashi, Yusuke Murata, Masahiro Ishida, Fumitoshi Yagishita, Masami Sakamoto, Tetsuya Sengoku and Hidemi Yoda
DOI: 10.1039/C4OB01508H, Communication

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Recent developments in transition metal-catalysed spiroketalisation
Rachelle Quach, Daniel F. Chorley and Margaret A. Brimble
DOI: 10.1039/C4OB01325E, Perspective

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Non-isoprenoid polyene natural products – structures and synthetic strategies
Katrina S. Madden, Fathia A. Mosa and Andrew Whiting
DOI: 10.1039/C4OB01337A, Review Article

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A Lewis acid-mediated conformational switch
Peter C. Knipe, Hannah Lingard, Ian M. Jones, Sam Thompson and Andrew D. Hamilton
DOI: 10.1039/C4OB01556H, Paper

The number of deaths due to heroin overdoses has severely increased in last decade, and regular consumption of heroin leads to serious health concerns.

Vaccination is one of the emerging choices among heroin rehabilitation therapies. In general, these vaccines contain heroin-like hapten as a pharmacophore that acts as an antagonist. This antagonist has high affinity for heroin receptors but does not activate them, hence reverses the effects of heroin. Because of inherent chemical instability, when entered in to bloodstream these anti-heroin drugs rapidly metabolise into several by-products, which makes development of effective vaccines against heroin particularly challenging.

Recently an American research group at National Institute on Drug Abuse (NIDA) lead by Professor Kenner Rice has reported the synthesis and immunological evaluation for a series of haptens.

The team has emphasised the hydrolytic stability of hapten scaffolds and envisioned that hapten with amido groups at both the C3 and C6 positions should be more stable than a hapten with an ester in one of those positions. Insertion of a 3-amino group and the construction of a C-6α-(2-oxo-propyl) group stereoselectively was the challenging task towards the synthesis of designed hapten derivatives. The group has tackled the synthetic hurdle by adopting convergent synthesis approach and validating the stereochemistry by single X ray crystallography.

Furthermore, in vivo Immunological studies of all three new synthetic haptens reveals that one derivative DiAmHap (3) is chemically more stable and better candidate for a heroin vaccine than 6-PrOxyHap (1) and DiPrOxyHap (2). This work is a very positive step towards the development of vaccines for heroin abuse.

Synthesis and immunological effects of heroin vaccines
Fuying Li, Kejun Cheng,  Joshua F. G. Antoline, Malliga R. Iyer, Gary R. Matyas, Oscar B. Torres, Rashmi Jalah, Zoltan Beck, Carl R. Alving, Damon A. Parrish, Jeffrey R. Deschamps, Arthur E. Jacobson and Kenner C. Rice
DOI: 10.1039/C4OB01053A

Check out the following HOT articles, these have been made free to access for a limited time:

Synthesis and immunological effects of heroin vaccines
Fuying Li, Kejun Cheng, Joshua F. G. Antoline, Malliga R. Iyer, Gary R. Matyas, Oscar B. Torres, Rashmi Jalah, Zoltan Beck, Carl R. Alving, Damon A. Parrish, Jeffrey R. Deschamps, Arthur E. Jacobson and Kenner C. Rice
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB01053A

Free to access until 21st August 2014

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6-Azido hyacinthacine A₂ gives a straightforward access to the first multivalent pyrrolizidine architectures
Giampiero D’Adamio, Camilla Parmeggiani, Andrea Goti, Antonio J. Moreno-Vargas, Elena Moreno-Clavijo, Inmaculada Robina and Francesca Cardona
Org. Biomol. Chem., 2014,12, 6250-6266
DOI: 10.1039/C4OB01117A

Free to access until 21st August 2014

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Relative contractile motion of the rings in a switchable palindromic [3]rotaxane in aqueous solution driven by radical-pairing interactions
Leah S. Witus, Karel J. Hartlieb, Yuping Wang, Aleksandrs Prokofjevs, Marco Frasconi, Jonathan C. Barnes, Edward J. Dale, Albert C. Fahrenbach and J. Fraser Stoddart
Org. Biomol. Chem., 2014,12, 6089-6093
DOI: 10.1039/C4OB01228C

Free to access until 21st August 2014

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Catalytic control over the formation of supramolecular materials
Rienk Eelkema and Jan H. van Esch
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB01108B

Free to access until 21st August 2014

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Comparison of the substrate selectivity and biochemical properties of human and bacterial γ-butyrobetaine hydroxylase
Anna M. Rydzik, Ivanhoe K. H. Leung, Grazyna T. Kochan, Nikita D. Loik, Luc Henry, Michael A. McDonough, Timothy D. W. Claridge and Christopher J. Schofield
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB01167H

Free to access until 21st August 2014

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Diaporine, a novel endophyte-derived regulator of macrophage differentiation
Hao Chen Wu, Hui Ming Ge, Le Yun Zang, Yun Cheng Bei, Zhi Yuan Niu, Wei Wei, Xiu Jing Feng, Sen Ding, Seik Weng Ng, Ping Ping Shen and Ren Xiang Tan
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB01123F

Free to access until 21st August 2014

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New reagents for detecting free radicals and oxidative stress
Mina Barzegar Amiri Olia, Carl H. Schiesser and Michelle K. Taylor
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB01172D

Free to access until 21st August 2014

Enantioselective synthesis of spiroacetals: the conquest of a long-sought goal in asymmetric catalysis
Lara Cala, Francisco J. Fañanás and Félix Rodríguez  
Org. Biomol. Chem., 2014,12, 5324-5330
DOI: 10.1039/C4OB00737A

Free to access until 1st August 2014

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Multivalent glycosylated nanoparticles for studying carbohydrate–protein interactions
Avijit K. Adak, Hong-Jyune Lin and Chun-Cheng Lin
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00827H

Free to access until 1st August 2014

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A simple approach to pyrrolylimidazole derivatives by azirine ring expansion with imidazolium ylides
Alexander F. Khlebnikov, Olesya A. Tomashenko, Liya D. Funt and Mikhail S. Novikov  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00865K

Free to access until 1st August 2014

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Enantioselective palladium catalyzed conjugate additions of ortho-substituted arylboronic acids to β,β-disubstituted cyclic enones: total synthesis of herbertenediol, enokipodin A and enokipodin B
Jeffrey Buter, Renée Moezelaar and Adriaan J. Minnaard  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB01085J

Free to access until 1st August 2014

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Conversion of S-phenylsulfonylcysteine residues to mixed disulfides at pH 4.0: utility in protein thiol blocking and in protein-S-nitrosothiol detection
B. D. Reeves, N. Joshi, G. C. Campanello, J. K. Hilmer, L. Chetia, J. A. Vance, J. N. Reinschmidt, C. G. Miller, D. P. Giedroc, E. A. Dratz, D. J. Singel and P. A. Grieco  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00995A

Free to access until 1st August 2014

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A tryptophan responsive fluorescent and wettable dual-signal switch
Xiaoyan Zhang, Jing Li, Ningmei Feng, Li Luo, Zhen Dai, Li Yang, Demei Tian and Haibing Li
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00792A

Free to access until 1st August 2014

Polyamine modification by acrolein exclusively produces 1,5-diazacyclooctanes: a previously unrecognized mechanism for acrolein-mediated oxidative stress
Ayumi Tsutsui, Rie Imamaki, Shinobu Kitazume, Shinya Hanashima, Yoshiki Yamaguchi, Masato Kaneda, Shinya Oishi, Nobutaka Fujii, Almira Kurbangalieva, Naoyuki Taniguchi and Katsunori Tanaka  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00761A

Free to access until 18th July 2014

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Catalytic functionalization of tertiary alcohols to fully substituted carbon centres
Long Chen, Xiao-Ping Yin, Cui-Hong Wang and Jian Zhou
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00718B

Free to access until 18th July 2014

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Pd-catalyzed carbonylation for the construction of tertiary and quaternary carbon centers with sp³ carbon partners
Wei Lu, Yang Li, Chao Wang, Dong Xue, Jian-Gang Chen and Jianliang Xiao
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00568F

Free to access until 18th July 2014

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Asymmetric synthesis of substituted NH-piperidines from chiral amines
Lekh Nath Gautam, Yijin Su, Novruz G. Akhmedov, Jeffrey L. Petersen and Xiaodong Shi  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00657G

Free to access until 18th July 2014

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Evaluation of 4-substituted styrenes as functional monomers for the synthesis of theophylline-specific molecularly imprinted polymers
Hazit Zayas, Clovia I. Holdsworth, Michael C. Bowyer and Adam McCluskey  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00517A

Free to access until 18th July 2014

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Synthesis of phosphaisocoumarin amidates via DIBAL-H-mediated selective amidation of phosphaisocoumarin esters
Yu-Juan Guo, Pei-Jiang Chen, Bo Wang and Ai-Yun Peng  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00663A

Free to access until 18th July 2014

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In(OTf)₃-catalysed one-pot versatile pyrrole synthesis through domino annulation of α-oxoketene-N,S-acetals with nitroolefins
Abhijeet Srivastava, Gaurav Shukla, Anugula Nagaraju, Girijesh Kumar Verma, Keshav Raghuvanshi, Raymond C. F. Jones and Maya Shankar Singh  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00781F

 

Free to access until 18th July 2014

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Improving alkynyl(aryl)iodonium salts: 2-anisyl as a superior aryl group
David J. Hamnett and Wesley J. Moran  
Org. Biomol. Chem., 2014,12, 4156-4162
DOI: 10.1039/C4OB00556B

Free to access until 4th July 2014

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Recent development of two-photon fluorescent probes for bioimaging
Dokyoung Kim, Hye Gun Ryu and Kyo Han Ahn
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00431K

Free to access until 4th July 2014

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A succinyl lysine-based photo-cross-linking peptide probe for Sirtuin 5
Karunakaran A. Kalesh and Edward W. Tate  
Org. Biomol. Chem., 2014,12, 4310-4313
DOI: 10.1039/C4OB00773E

 

Free to access until 4th July 2014

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Marine bacteria from the Roseobacter clade produce sulfur volatiles via amino acid and dimethylsulfoniopropionate catabolism
Nelson L. Brock, Markus Menke, Tim A. Klapschinski and Jeroen S. Dickschat  
Org. Biomol. Chem., 2014,12, 4318-4323
DOI: 10.1039/C4OB00719K

Free to access until 4th July 2014

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Hydrogen bond directed epoxidation: diastereoselective olefinic oxidation of allylic alcohols and amines
Stephen G. Davies, Ai M. Fletcher and James E. Thomson  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00616J

Free to access until 4th July 2014

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An intracellularly activatable, fluorogenic probe for cancer imaging
Ruisong Tian, Mingjie Li, Jin Wang, Min Yu, Xiuqi Kong, Yupeng Feng, Zeming Chen, Yuxi Li, Weiqiang Huang, Wenjie Wu and Zhangyong Hong  
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00297K

Free to access until 4th July 2014

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Palladium mediated intramolecular multiple C–X/C–H cross coupling and C–H activation: synthesis of carbazole alkaloids calothrixin B and murrayaquinone A
Srinivasan A. Kaliyaperumal, Shyamapada Banerjee and Syam Kumar U. K.
Org. Biomol. Chem., 2014, Advance Article
DOI: 10.1039/C4OB00493K

Free to access until 4th July 2014