Results 61 to 70 of about 33,483 (272)

Dynamic Control of Nucleic Acids Self‐Assembly and Expression Using Photoswitches

Chemistry – A European Journal, EarlyView.
We review here the recent progress made in the design of molecular photoswitches, and highlight their implementation for the dynamic control over nucleic acids self‐assembly and expression. ABSTRACT Synthetic nucleic acids have become readily available and now constitute versatile building blocks in materials science—where they can be used to engineer ...
Noemí Nogal, Hugo Laigle, Maxime Mansy, Sébastien Ulrich, Mathieu Surin   +4 more
wiley   +1 more source

Strain Release of 1‐Azabicyclo[1.1.0]butanes as a Gateway to Highly Functionalized Azetidines: New Strategies and Structural Motifs

Chemistry – A European Journal, EarlyView.
Over the past decade, the interest in azetidines has continuously risen, by virtue of their highly appealing pharmaceutical properties. Monocyclic, spirocyclic, and bridged azetidines can be accessed by leveraging 1‐azabicyclo[1.1.0]butanes as precursors.
Yuri Gelato, Philipp Natho, Marco Colella, Renzo Luisi   +3 more
wiley   +1 more source

5-Chloro-5′′-(4-chlorobenzylidene)-4′-(4-chlorophenyl)-1′′-ethyl-1′-methyldispiro[indoline-3,2′-pyrrolidine-3′,3′′-piperidine]-2,4′′-dione

Acta Crystallographica Section E, 2014
Two spiro links are found in the title compound, C31H28Cl3N3O2, one connecting the piperidine and pyrrolidine rings, and the other connecting the pyrrolidine ring and indole residue.
I. S. Ahmed Farag, Adel S. Girgis, A. A. Ramadan, A. M. Moustafa, Edward R. T. Tiekink   +4 more
doaj   +1 more source

Precision Chemistry for Protein Lysine Modification

Chemistry – A European Journal, EarlyView.
Selective modification of lysine residues is challenging due to their similar intrinsic reactivity. Inspired by enzymatic recognition, ligand‐guided electrophiles enable site‐selective labeling and functionalization, while ligand‐guided catalyses achieve regioselective installation of bio‐relevant post‐translational modifications.
Mayu Onoda, Motomu Kanai
wiley   +1 more source

Organocatalytic Formal (3+2+1)‐Cycloaddition of Allenoates, Michael Acceptors, and Carbaldehydes

Chemistry – A European Journal, EarlyView.
The use of secondary amine Lewis base organocatalysts allows for the unprecedented activation of allenoates for formal (3+2+1)‐cycloadditions with Michael acceptors and aromatic carbaldehydes. ABSTRACT Employing secondary amines as covalently interacting Lewis basic organocatalysts allows for the activation of electron‐deficient allenes (allenoates ...
David Naderer, Alexander Pötscher, Katharina Eder, Uwe Monkowius, Markus Himmelsbach, Mario Waser   +5 more
wiley   +1 more source

A New and Efficient Method for the Synthesis of 3,4-Disubstituted Pyrrolidine-2,5-diones

Molecules, 2012
A newly found reaction for the synthesis of 3,4-disubstituted 1-hydroxy-pyrrolidine-2,5-diones from 3-substituted coumarins and nitromethane has been elaborated. The reaction involved a simple and convenient experimental procedure.
Rositca D. Nikolova, Nevena I. Petkova, Eleonora D. Ilieva   +2 more
doaj   +1 more source

Stereoretentive Nucleophilic Aromatic Substitution Accesses Atropisomeric 4‐Amino‐N‐Arylquinolinium Salts

Chemistry – A European Journal, EarlyView.
Quinolin‐4‐ones were converted to chloroquinolinium salts, allowing formation of axially chiral aminoquinolinium salts via an enantioretentive SNAr reaction with a variety of amine nucleophiles. The salts have a high rotational barrier, with a racemization half‐life of ∼1000s of years.
Darren Holmes, Nia Foster, Saima Ansari, Paul Kavanagh, Paul Dingwall, Peter C. Knipe   +5 more
wiley   +1 more source

Crystal structure of ethyl (2S,2′R)-1′-benzyl-3-oxo-3H-dispiro[1-benzothiophene-2,3′-pyrrolidine-2′,11′′-indeno[1,2-b]quinoxaline]-4′-carboxylate

Acta Crystallographica Section E: Crystallographic Communications, 2015
In the title compound, C35H27N3O3S, the spiro-linked five-membered rings both adopt twisted conformations. The pyrrolidine ring makes dihedral angles of 80.5 (1) and 77.4 (9)° with the benzothiophene ring system and the quinoxaline ring system ...
J. Govindaraj, R. Raja, M. Suresh, R. Raghunathan, A. SubbiahPandi   +4 more
doaj   +1 more source

Dual‐Functional Polystyrene‐Based Borate Complexes: Recyclable Alkyl Radical Sources and Photodegradable Absorbents

Chemistry – A European Journal, EarlyView.
Dual‐functional polystyrene‐based polymers bearing 2,2′‐(pyridine‐2,6‐diyl)diphenol (PDP) moieties form photoexcitable alkyl borate complexes: (i) As recyclable radical sources, they enable Giese‐type additions with facile purification by reprecipitation and demonstrate proof‐of‐concept for polymer recovery (50% PDP regeneration).
Nami Jimba, Ryosei Ishii, Kazuki Wako, Tomoki Hirohata, Kosuke Sato, Tomohiro Kubo, Kotaro Satoh, Yuto Sumida, Hirohisa Ohmiya, Shinsuke Inagi   +9 more
wiley   +1 more source

The crystal structures of 6′-(4-chlorophenyl)- and 6′-(4-methoxyphenyl)-6a′-nitro-6a′,6b′,7′,9′,10′,12a′-hexahydro-2H,6′H,8′H-spiro[acenaphthylene-1,12′-chromeno[3,4-a]indolizin]-2-one

Acta Crystallographica Section E: Crystallographic Communications, 2019
In the title compounds, C32H25ClN2O4 (I) and C33H28N2O5 (II), the six-membered pyran and piperidine rings adopt envelope and chair conformations, respectively. The five-membered pyrrolidine rings adopt twist conformations. Compound (II) crystallizes with
S. Syed Abuthahir, M. NizamMohideen, V. Viswanathan, D. Velmurugan, J. Nagasivarao   +4 more
doaj   +1 more source