27304-20-7Relevant academic research and scientific papers
Synthesis of the tetrahydrofuran unit of varitriol and γ- butyrolactones from 5-oxabicyclo[2.1.1]hexane derivative via oxidative cleavage reactions
Mahadevegowda, Surendra H.,Khan, Faiz Ahmed
, p. 2266 - 2269 (2014)
A formal synthesis of marine-derived antitumor natural product varitriol from a 5-oxabicyclo[2.1.1]hexane derivative is described. A tetrahydrofuran unit of varitriol embedded with four contiguous stereocenters was synthesized with an overall yield of 10.2% in 11 steps from an oxa-bicyclic system. An unprecedented oxidative cleavage reaction involving scissoring of two CC bonds at oxa-quaternary carbon of THFs leading to γ-butyrolactones was reported and a plausible mechanism has been proposed.
Conversion of 2,3-O-cyclohexylidene-(D)-ribonolactone into 2,3-O-cyclohexylidene-(L)-ribonolactone
Takano, Seiichi,Inomata, Kohei,Ogasawara, Kunio
, p. 2413 - 2415 (1988)
A convenient method for the chirality inversion of 2,3-O-cyclohexylidene-D-ribonolactone to 2,3-O-cyclohexylidene-L-ribonolactone has been established.
Novel synthesis method for synthesizing remdesivir
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, (2021/08/14)
The invention discloses a novel synthesis method for synthesizing remdesivir. According to the synthesis method disclosed by the invention, D-ribose is taken as a raw material and is subjected to a series of reactions such as oxidation, cyclohexanone protection, silanization protection, substitution, substitution, deprotection, coupling, deprotection and the like to synthesize the remdesivir. The post-treatment operation is optimized, and the method has the advantages of being short in reaction time, high in yield, low in cost, suitable for industrial production and the like. The structure of the remdesivir provided by the invention is shown in the specification.
Organotransition Metal Modified Sugars, Part 10. Chromium Iminoglycosylidenes: Synthesis and Application to Photoinduced C-Glycosidation
Doetz, Karl Heinz,Klumpe, Markus,Nieger, Martin
, p. 691 - 699 (2007/10/03)
The iminoglycosylidene complexes 3a,b, 9, and 16a,b are conveniently prepared from the sugar lactams 2a,b, 8, and 15a,b by reaction with K2Cr(CO)5 and subsequent deoxygenation with trimethylsilyl chloride (TMSCl). The Cr(CO)5-stabilized carbene moiety of the imino-D-ribo-pyranosylidene complexes 9 and 16a,b has been exploited in the photoinduced generation of ketene-like species on irradiation with UV light. These intermediates were trapped with methanol to produce the methyl 2,6-imino-D-allonates 10 and 17a,b. The C-glycosidation is β-selective and has been applied futher to the preparation of the galactosyl 2,6-imino-D-allonate 19. Solvent effects suggest that the diastereoselectivity originates in the chromium fragment, which shields the re face of the proposed ketene intermediate. - Keywords: chromium; carbene complexes; glycosides; iminosugars; photolysis
Reinvestigation of the synthesis of (2R,3R) 2,3-(cyclohexylidenedioxy)-4-cyclopentenone as possible building block for the synthesis of carbocyclic nucleosides
Marien,Esmans,Lemiere,Dommisse
, p. 205 - 224 (2007/10/03)
An in depth study of the four-steps synthesis of (2R,3R) 2,3-(cyclohexylidenedioxy)-4-cyclopentenone (5) from D-ribonolactone (1) is described. From these experiments we must conclude that the overall yield reported in the literature (65%) is overestimated. All compounds have been throughly investigated by 1H- and 13C-NMR spectroscopy.
A new synthesis of D-ribonolactone from D-ribose by pyridinium chlorochromate oxidation
Liu,Caperelli
, p. 933 - 934 (2007/10/02)
2,3-O-Cyclohexylidene-D-ribonolactone is prepared directly from 2,3-O-cyclohexylidene-D-ribose by pyridinium chlorochromate (PCC) oxidation in 55-60% yield.
Enantiomerically pure polyhydroxylated acyliminium ions. Synthesis of the glycosidase inhibitors (-)-swainsonine and (+)-castanospermine
Miller, Scott A.,Chamberlin, A. Richard
, p. 8100 - 8112 (2007/10/02)
Hydroxylactams, which are useful precursors of acyl iminium ions for cationic cyclization, are most often prepared by hydride reduction of imides. This procedure is not directly applicable, however, to the enantioselective preparation of any highly substituted hydroxy lactam that would be derived from a meso imide, since such a reduction with the usual achiral agents must produce a racemic product. Two enantioselective methods of preparing representative examples of this type of substituted hydroxylactam have therefore been explored. Reduction of a meso imide with a number of enantiomerically pure chiral reducing agents has been found to give up to 56% ee of the corresponding hydroxylactam. Much higher levels of enantiomeric purity are readily obtainable by direct synthesis from monosaccharide lactones derived from either ribose or lyxose, affording either enantiomeric series of hydroxy lactams, (+)-9α, 14-16, and (-)-9α, 20-23, respectively. One such hydroxylactam, 23 has been converted into the mannosidase inhibitor (-)-swainsonine via a synthetic route that features a novel multiple reduction of a vinylogous N-acylurethane to establish the correct ring juncture stereochemistry. Extension of the monosaccharide strategy to the enantioselective synthesis of six-membered-ring hydroxylactams also allows a facile preparation of 29, leading to the glucosidase inhibitor (+)-castanospermine and the new indolizidine alkaloid 1,8a-diepicauistanospermine.
