The synthesis of 1,3-dioxolan-2-ylnucleosides and related chemistry is described. We have shown that 2-methoxy-1,3-dioxolane (6) reacts with silylated thymine and trimethylsilyl triflate to give the acyclic formate ester 1-[2-(formyloxy)ethyl]thymine (8) rather than 1-(1,3-dioxolan-2-yl)thymine (7). A tentative mechanism which could explain this result is discussed. On the other hand, 2-methoxy-1,3-dioxolane 13c reacts with silylated bases to give [4,5-bis(hydroxymethyl)-1,3-dioxolan-2-yl]nucleosides, thus representing the first examples of this novel class of compounds. The nature of the nucleobase and the hydroxyl protecting groups was found to have great influence on the reaction and on the stability of the nucleosides. Compounds 16 and 18 were found to be inactive when tested for anti HIV-1 activity in vitro.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/jo960008k | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Light-Dependent Chemoselective Amide or Thioamide Ligation of Acylsilanes with Amines using Elemental Sulfur.
Chemistry
January 2025
Xi'an Jiaotong University, School of Chemistry, No.28, West Xianning Road, 710049, Xi'an, CHINA.
Due to the diverse chemical and physical properties of functional groups, mild and controllable ligation methods are often required to construct complex drugs and functional materials. To make diverse sets of products with tunable physicochemical properties, it is also useful to employ complimentary ligation methods that adopt the same starting materials. Here, we disclose the efficient and modular synthesis of amides or thioamides through the chemical ligation of acyl silanes with amines, simply by turning a light on or off.
View Article and Find Full Text PDFHydroalkylation of Vinylarenes by Transition-Metal-Free In Situ Generation of Benzylic Nucleophiles Using Tetramethyldisiloxane and Potassium tert-Butoxide.
Angew Chem Int Ed Engl
December 2024
Centre for Catalysis Research and Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada.
Hydrosilanes and Lewis bases are known to promote various reductive defunctionalizations, rearrangements, and silylation reactions, facilitated by enigmatic silicon/Lewis base-derived reactive intermediates. Despite the wide variety of transformations enabled by this reagent combination, no examples of intermolecular C(sp)-C(sp) forming reactions have been reported. In this work, we've identified 1,1,3,3-tetramethyldisiloxane (TMDSO) and KOBu as a unique reagent combination capable of generating benzylic nucleophiles in situ from styrene derivatives, which can subsequently react with alkyl halides to give a new C(sp)-C(sp) linkage via formal hydroalkylation.
View Article and Find Full Text PDFUnderstanding asymmetric hydrogenation of alkenes catalyzed by the first-row transition metal Fe: a first-principles exploration.
Phys Chem Chem Phys
January 2025
Department of Chemistry, Visva-Bharati University, Santiniketan, West Bengal-731235, India.
First-principles analyses were performed for understanding the mechanistic details of Fe-catalysed asymmetric hydrogenation of alkenes in the presence of silane that has recently been experimentally realized. The catalytic hydrogenation is expected to proceed through initial hydride transfer from Fe-H to the CC bond of alkene, followed by σ-bond metathesis of hydrosilane to afford a chiral alkane product and an iron silyl species, which then reacts with H to regenerate the iron hydride species another σ-bond metathesis. The mechanistic details and the origin of the regioselectivity and stereoselectivity of these reactions are understood on the basis of detailed potential energy surface analysis, charge transfer and noncovalent interactions involved therein, strain energy and isodesmic studies in the solvated stage.
View Article and Find Full Text PDFOrganometallic Chemistry of Propargylallenes: Syntheses, Reactivity, Molecular Rearrangements and Future Prospects.
Molecules
November 2024
School of Chemistry, University College Dublin, Belfield, D04 V1W8 Dublin 4, Ireland.
Alkynylallenes offer the varied reactivity patterns of two different multiple bond linkages either separately or in concert. Initially, a short overview of their syntheses, structures, rearrangement mechanisms and synthetic utility, especially when treated with transition metal reagents such as gold(I), silver(I), platinum metals or metal carbonyls, is presented. Subsequently, we focus on the particular case of 1,2-dien-5-ynes (propargylallenes), whereby the shortness of the single atom bridge, and the consequent proximity of the allenyl and alkynyl moieties, facilitates metal-mediated interactions between them.
View Article and Find Full Text PDFVisible light-mediated formal alkylation and [4+1]-cycloaddition strategies of silyl enol ethers with aryldiazoacetates.
Chem Commun (Camb)
December 2024
Universidade Estadual de Campinas, Instituto de Química, CEP 13083-862, Campinas, SP, Brazil.
A reaction sequence of visible light-mediated cyclopropanation/acid-promoted ring-opening is described for the formal alkylation of silyl enol ethers with aryldiazoacetates. Under the same conditions, the Danishefsky's diene can react with aryldiazoacetates to afford [4+1]-cycloaddition adducts. Key mechanistic aspects are proposed based on experimental evidence and DFT calculations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!