38838-08-3Relevant academic research and scientific papers
Synthesis of 6-amino-6-deoxy-2,3,4,5-tetra-O-methyl-D-galactonic acid, a key precursor of a stereoregular polyamide
Romero Zaliz, Carmen L.,Varela, Oscar
, p. 689 - 701 (2001)
The title compound (17) was synthesized by two alternative sequences, starting from D-galactose diacetonide (1) and from methyl 6-O-tosyl-α-D-galac-topyranoside (9). Compound 1 was converted into the 6-bromo-6-deoxy derivative 2 or mesylated to 3. Nucleop
Conversion of alcohols to bromides using a fluorous phosphine
Desmaris, Laurence,Percina, Nathalie,Cottier, Louis,Sinou, Denis
, p. 7589 - 7591 (2007/10/03)
Reaction of alcohols with the fluorous phosphine-carbon tetrabromide complex in toluene or in a two-phase toluene-FC-72 system afforded the corresponding bromides in good yields. The fluorous-phosphine oxide is readily separated by liquid-liquid extraction, providing an alternative to the homogeneous triphenylphosphine-carbon tetrachloride conversion, as well as to the polymer-supported phosphine method. The fluorous phosphine oxide could be reduced and the product reused.
Synthesis of amino-substituted hexo- and heptopyranoses from D-galactose
Streicher, Benedikt,Wuensch, Bernhard
, p. 2375 - 2385 (2007/10/03)
After condensation of D-galactose with two equivalents of acetone, the last free hydroxy group was transformed into an acylated amino group by Swern oxidation, oxime formation, LiAlH4 reduction and acylation. The intermediate aldehyde was homol
A new approach to some 1,6-dideoxy 1,6-epithio sugars
Driguez, Hugues,McAuliffe, Joseph C.,Stick, Robert V.,Tilbrook, Matthew G.,Williams, Spencer J.
, p. 343 - 348 (2007/10/03)
The treatment of hexopyranosyl bromides, also activated at C6 (Br, OTs, OMs), with H2S/HCONMe2 under basic conditions gives rise to 1,6-dideoxy 1,6-epithio sugars. One such sugar has been further transformed into the synthetically useful 3,4-anhydro-1,6-dideoxy-1,6-epithio-β-D-galactose. The treatment of this epoxide with sodium azide and with cyclohexylamine is described. An analogous treatment of one doubly activated hexopyranosyl bromide with sodium hydrogen selenide has led to a novel 1,6-dideoxy 1,6-episeleno sugar which displayed interesting n.m.r. spectra. Finally, in an attempt to prepare 1,6-dideoxy 1,6-epidithio sugars, a tetraalkylammonium tetrathiomolybdate reagent was found to be the reagent of choice for converting doubly activated hexopyranosyl bromides into 1,6-dideoxy 1,6-epithio sugars.
Synthesis and Properties of Glucose and Galactose Phosphonate Derivatives
Padyukova, N. Sh.,Afsar, S.,Dixon, H. B. F.,Karpeiskii, M. Ya.
, p. 328 - 331 (2007/10/02)
Phosphonate analogs of glucose-6-phosphate and galactose-6-phosphate, namely, 6-deoxy-6-phosphono-α,β-D-glucopyranose and 6-deoxy-6-phosphono-α,β-D-galactopyranose, were synthesized.They were shown to be weak inhibitors of 1L-myo-inositol-1-phosphatase. Key words: 6-deoxy-6-phosphono-α,β-D-glucopyranose, 6-deoxy-6-phosphono-α,β-D-galactopyranose, 1L-myoinositol-1-phosphatase, inhibitors
The mechanism of the hydroxyl → halogen exchange reaction in the presence of triphenylphosphine, N-bromosuccinimide, and N,N-dimethylformamide: Application of a new Vilsmeier-type reagent in carbohydrate chemistry
Hodosi,Podanyi,Kuszmann
, p. 327 - 342 (2007/10/02)
Triphenylphosphine reacts with N-bromosuccinimide to give a phosphonium salt (13), which reacts with N,N-dimethylformamide to afford N,N-dimethylsuccinimidomethaniminium bromide (16). The latter product reacts with an alcohol to give an O-formiminium compound 17, and, in the presence of an alcohol, 13 is transformed into an alkoxyphosphonium intermediate (14). Both 4 and 17 can be converted by heating into an alkyl bromide. Hydrolysis of 17 gives the corresponding O-formyl derivative. Reaction of 1.2:5.6-di-O-isopropylidene-α-D-glucofuranose with 13 or 16 gave 6-bromo-6-deoxy-1,2:3,5-di-O-isopropylidene-α-D-glucofuranose and a possible mechanism for these reactions is suggested. An efficient method for the preparation of 3-deoxy-3-halogeno-1,2:5,6-di-O-isopropylidene-α-D-allofuranose derivatives and a new procedure for selective O-formylation are described.
DESIGN AND REACTIVITY OF ORGANIC FUNCTIONAL GROUPS - 2-PYRIDYLSULFONATES AS NUCLEOFUGAL ESTERS: REMARKABLY MILD TRANSFORMATIONS INTO HALIDES AND OLEFINS
Hanessian, Stephen,Kagotani, Masahiro,Komaglou, Kossi
, p. 1115 - 1120 (2007/10/02)
The novel 2-pyridylsulfonate esters are excellent leaving groups for the preparation of bromides and olefins under very mild reaction conditions.Displacements occur with inversion of configuration.
New Synthetic Bromination Procedures for use in Radiolabelling-Chemistry: Reaction of C-Metallated Derivatives of Carbohydrates with Bromide, in the Presence of Mild Oxidizing Agents
Neeser, Jean-Richard,Hall, Laurance D.,Balatoni, Julius A.
, p. 1018 - 1027 (2007/10/02)
In the presence of 2 mol-equiv. of AcONa, both triglycosylborane 1 and dicyclohexylglycosylborane 2 readily react with bromine chloride generated in situ from bromide and N-chlorosuccinimide (NCS) to give the bromo-sugar 3 (75 and 60 percent, resp.).The use of the BH3-THF/bromide/NCS/2 AcONa procedure permits the rapid, face-specific synthesis of 6 (58percent uptake of bromine) and face-selective synthesis of 8/9 (71percent uptake of bromine), from vinyl ether derivatives 5 and 7, respectively.The dicyclohexylborane/bromide/NCS/2 AcONa procedure leads to the fast and quantitative conversion of 11 to the bromosugar 12 (91percent).Hydroboration-transmetallation sequences give access to C-mercuriated carbohydrates 13 (71percent) and 14 (78percent).The bis(glycosyl)mercury derivative 13 is spontaneously cleaved by reaction with one equivalent of bromide/chloramine-T/aqueous HCl-solution to give 3 (87percent) and 14 (76percent).Hydrostannylation of acetylenic sugar 15 gave the (E)-stannylvinyl derivative 16 as the major product.This latter precursor 16 is spontaneously cleaved by the bromide/chloramine-T/aqueous HCl-solution reagent to give the bromovinyl sugar-17 (96percent).
DESIGN AND REACTIVITY OF ORGANIC FUNCTIONAL GROUPS: THE HIGHLY CRYSTALLINE 2-ALKOXY N,N'-DIPHENYL-1,3,2-DIAZAPHOSPHOLANES AND THEIR FACILE CONVERSION INTO ALKYL HALIDES
Hanessian, Stephen,Leblanc, Yves,Lavallee, Pierre
, p. 4411 - 4414 (2007/10/02)
Functionalization of alcohols as 2-alkoxy N,N'-diphenyl-1,3,2-diazaphospholanes affords highly crystalline derivatives useful for characterization purposes.These tervalent phosphorus derivatives undergo facile and mild conversion into the corresponding alkyl halides with inversion of configuration.
