Results 41 to 50 of about 1,577 (174)

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

Studies on Some Dipolar Cycloaddition Reactions [PDF]

ChemInform, 2004
AbstractFor Abstract see ChemInform Abstract in Full Text.
openaire   +2 more sources

Synthesis, Physicochemical Characteristics, Self‐Assembly and Encapsulation Ability of per‐Ethylene‐Glycol‐Functionalized Resorcin[4]Arenes and Their Molecular Capsules: On the Road to Liquid Capsules

Chemistry – A European Journal, EarlyView.
Per‐ethylene‐glycol (EG)‐functionalized resorcin[4]arenes containing 12, 16, and 20 EG groups namely compounds 1d, 1e, and 1f, respectively, were prepared and found to self‐assemble, in organic solvents, into hexameric capsules. These capsules are more dynamic than the ones prepared based on alkyl substituted resorcin[4]arenes.
Gangadhara Angajala, Inbar Horin, Tamar Evan‐Salem, Yoram Cohen   +3 more
wiley   +1 more source

Synthesis and cytotoxic evaluation of substituted 3-(3′-indolyl-/3′-pyridyl)-isoxazolidines and bis-indoles

Acta Pharmaceutica Sinica B, 2012
Regio- and stereoselective 1,3-dipolar cycloadditions of C-(3-indolyl)-N-phenylnitrone (10) were carried out with different mono-substituted, disubstituted and cyclic dipolarophiles under mono-mode microwave irradiation to obtain substituted 3-(indol-3 ...
Vishal Sharma, Raman Kalia, Tilak Raj, Vivek K. Gupta, Nitasha Suri, Ajit K. Saxena, Deepak Sharma, Surinderjit S. Bhella, Gurpinder Singh, Mohan Paul S. Ishar   +9 more
doaj   +1 more source

1,3-Dipolar cycloadditions of azomethine imines

Organic & Biomolecular Chemistry, 2015
Azomethine imines react with alkenes and alkynes to give pyrazolines, pyrazolidines, pyrazolopyridines, indazoloisoquinolines, pyrazolo[1,5- a ]isoquinolines and pyrazolopyrazolones through regio-, stereo- and enantioselective 1,3-dipolar cycloadditions.
Nájera, Carmen, Sansano, Jose M., Yus, Miguel   +2 more
openaire   +4 more sources

Isotelluroureas for Asymmetric C1 Ammonium Enolate Reactions

European Journal of Organic Chemistry, EarlyView.
Chiral isotelluroureas are powerful catalysts for a variety of C─C bond forming C1 ammonium enolate transformations. Isotelluroureas (ITeUs) have recently been introduced as a novel class of highly nucleophilic Lewis base catalysts. Herein, we systematically screened them for their potential to facilitate C1 ammonium enolate transformations and ...
Fereshteh Khorasani, Lotte Stockhammer, Magdalena Piringer, Mario Waser   +3 more
wiley   +1 more source

Synthesis of 2-substituted 9-oxa-guanines {5-aminooxazolo[5,4-d]pyrimidin-7(6H)-ones} and 9-oxa-2-thio-xanthines {5-mercaptooxazolo[5,4-d]pyrimidin-7(6H)-ones}

Beilstein Journal of Organic Chemistry, 2008
Oxazolo[5,4-d]pyrimidines can be considered as 9-oxa-purine analogs of naturally occurring nucleic acid bases. Interest in this ring system has increased due to recent reports of biologically active derivatives.
Subrata Mandal, Wen Tai Li, Yan Bai, Jon D. Robertus, Sean M. Kerwin   +4 more
doaj   +1 more source

Retro‐Hetero‐Michael Addition Strategies in Organic Synthesis

European Journal of Organic Chemistry, EarlyView.
In this review, synthetic approaches to carbo‐ and heterocyclic compounds, including natural products, published in the last 15 years (2011–2025) which have either relied upon or included a retro‐hetero‐Michael addition step at any stage are discussed.
Dina Scarpi, Ernesto G. Occhiato
wiley   +1 more source

Think Beyond The Core: Computationally Decoding the Hydrophilic Corona of Drug‐Loaded Polymer Micelles

Small, EarlyView.
Drug‐loaded ABA‐type triblock copolymer micelles with a hydrophobic poly(2‐n‐butyl‐2‐oxazine) core (B‐block) and hydrophilic coronas (pEG, pDMAA, pSAR (A‐block)) are investigated by all‐atom molecular dynamics simulations at 20% and 60% curcumin loadings.
Maksym Karachevtsev, Josef Kehrein, Terttu Hukka, Alex Bunker, Mikko Karttunen, Robert Luxenhofer   +5 more
wiley   +1 more source

The Fragmentation of 2,3-Dihydroisothiazol-3-one 1,1-Dioxide Derivatives: A Novel Cheletropic Process

CHIMIA, 1992
Adducts obtained by 1,3-dipolar cycloadditions to 2,3-dihydroisothiazol-3-one 1,1-dioxides are inclined to undergo a cheletropic process, by which the newly formed heterocyclic part undergoes aromatization, while SO2 is extruded and an ...
Kaspar F. Burri
doaj   +2 more sources