Alkynylation of Pentose Derivatives with Stereochemical Fidelity: Implications for the Regioselectivity of Alkynyl Diol Cycloisomerizations to Cyclic Enol Ethers
作者:Frank E. McDonald、Dian Ding、Andrew J. Ephron、John Bacsa
DOI:10.1021/acs.orglett.9b01024
日期:2019.5.3
This work characterizes a previously undetected epimerization in the preparation of alkynyl diols from pentose precursors utilizing the Ohira–Bestmann reagent. Lithium trimethylsilyldiazomethane (Colvin reagent) additions to the d-ribose and d-lyxose-derived benzylidene acetals provide the respective alkynyl diol stereoisomers, without epimerization. Regioselective tungsten-catalyzed cycloisomerizations
1,5-Anhydro-β-D-ribofuranose and the “Monoacetone Anhydroriboses” of Levene and Stiller
作者:Erik Vis、Hewitt G. Fletcher
DOI:10.1021/ja01562a040
日期:1957.3
Synthesis of Differently Protected 1‐<i>C</i>‐Methyl‐Ribofuranoses Intermediates for the Preparation of Biologically Active 1′‐<i>C</i>‐Methyl‐Ribonucleosides
Starting from D-ribose, differently protected 1-C-methyl-D-ribofuranoses have been prepared as intermediates for the synthesis of variously modified 1'-C-methyl-ribonucleosides, a class of compounds potentially endowed with interesting biological activity.
Configurational and conformational studies on some benzylidene derivatives of d-ribose and di-β-d-ribofuranose 1,5′:1′,5-dianhydride
作者:T.B. Grindley、W.A Szarek
DOI:10.1016/s0008-6215(00)82758-5
日期:1972.11
diverse conditions yields a variety of products, most of which are formed as mixtures of diastereoisomers. The conformations assumed by the furanose rings in the 2,3- O -benzylidene-β- D -ribose derivatives are discussed in relation to the coupling constants obtained by comparing the experimental and computed n.m.r. spectra.