89160-13-4Relevant academic research and scientific papers
A Pd-catalyzed approach to (1→6)-linked C-glycosides
Koester, Dennis C.,Leibeling, Markus,Neufeld, Roman,Werz, Daniel B.
scheme or table, p. 3934 - 3937 (2010/11/17)
A flexible and robust method for the assembly of (1→6)-linked C-glycosidic disaccharides is presented. The key reaction is a Pd-catalyzed coupling of 1-iodo-or 1-triflato-glycals with alkynyl glycosides. Reinstallation of the native hydroxyl group pattern
Glycosyl iodides. History and recent advances
Meloncelli, Peter J.,Martin, Alan D.,Lowary, Todd L.
scheme or table, p. 1110 - 1122 (2009/09/05)
The use of glycosyl iodides as an effective method for the preparation of glycosides has had a recent resurgence in carbohydrate chemistry, despite its early roots in which these species were believed to be of limited use. Renewed interest in these specie
Synthesis and partial biological evaluation of a small library of differentially-linked β-C-disaccharides
Postema, Maarten H. D.,Piper, Jared L.,Jie Shen, Lei Liu,Faust, Marcus,Andreana, Peter
, p. 4748 - 4754 (2007/10/03)
The synthesis of a small library of differentially-linked β-C-disaccharides has been carried out through the use of a radical allylation-RCM strategy. Acids 6 were prepared by Keck allylation of a suitable carbohydrate-based radical precursor, followed by
Linear total synthetic routes to β-D-C-(1,6)-linked oligoglucoses and oligogalactoses up to pentaoses by iterative Wittig olefination assembly
Dondoni, Alessandro,Marra, Alberto,Mizuno, Mamoru,Giovannini, Pier Paolo
, p. 4186 - 4199 (2007/10/03)
Two complementary routes, A and B, have been followed for the stepwise iterative assembly of β-D-(1,6)-glucopyranose and galactopyranose residues through methylene bridges. In route A the building block was constituted by 2,3,4-tri-O-benzyl-6-O-tert-butyldiphenylsilyl (O-TBDPS) β-linked galactosylmethylenephosphorane, while in route B the building block was a β-linked formyl C-glycopyranoside with a similar orthogonal protection of hydroxy groups. In route A each cycle consisted of the reaction of the phosphorane building block with a sugar residue bearing a formyl group at the C-5 carbon atom (coupling) and transformation of the O-TBDPS-protected primary alcohol into the formyl group (arming). Accordingly, route A is defined as the aldehyde route. On the other hand, each cycle in route B involved the coupling of the sugar aldehyde building block with a substrate bearing a phosphorus ylide at C-6 and introduction of the phosphonium group in the arming step as a precursor of the ylide functionality. Accordingly, route B is defined as the ylide route. The efficiency of route A proved to be seriously hampered by the 1,2-elimination of BnOH under the basic reaction conditions of the Wittig olefination, giving rise to the formation of substantial amounts of enopyranose. On the other hand, the ylide route B proved to be more efficient since very good yields (70-93%) of the isolated Wittig products were obtained throughout four consecutive cycles. Individual olefins and polyolefins obtained by routes A and B using gluco and galacto substrates were reduced and debenzylated in one pot by H2/Pd(OH)2 to give the corresponding β-D-C-(1,6)-linked oligosaccharides up to the pentaose stage. The latter compounds were fully characterized by high-field NMR spectroscopy (500 MHz).
A Ramberg-Baecklund approach to the synthesis of C-glycosides, C-linked disaccharides, and C-glycosyl amino acids
Paterson, Duncan E.,Griffin, Frank K.,Alcaraz, Marie-Lyne,Taylor, Richard J. K.
, p. 1323 - 1336 (2007/10/03)
Synthetic applications of exo-glycals, derived from S-glycoside dioxides using the Meyers variant of the Ramberg-Baecklund rearrangement, are described. These include a formal synthesis of a β-glycosidase inhibitor 12 and an efficient route to spirocyclic glucose derivatives 17 and 18. The synthesis of C-linked disaccharides 24, 31, and 38 and the C-glycosyl amino acid 49 using the Ramberg-Baecklund rearrangement is also reported. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
An olefin metathesis route for the preparation of (1 → 6)-linked C-disaccharide glycals. A convergent and flexible approach to C-saccharide synthesis
Postema, Maarten H. D.,Calimente, Daniel,Liu, Lei,Behrmann, Tonja L.
, p. 6061 - 6068 (2007/10/03)
A convergent route to a variety of C-1-disaccharide glycals based on the olefin metathesis reaction of enol ethers and alkenes is described. The DCC-mediated coupling reaction of a variety of pentose enitols (1a-c) with a number of C-5- and C-6-monosaccharide carboxylic acids (2a-e) gave the corresponding esters 3a-1 in good yield. Methylenation of these compounds was followed by ring-closing metathesis, mediated by the Schrock molybdenum catalyst 8 in warm toluene, to provide the target C-disaccharide glycals 5a-1. The formed enol ether double bond in 5a was then transformed, via standard manipulations, into a variety of C-disaccharide derivatives 21-25.
Ramberg - Backlund approaches to the synthesis of C-linked disaccharides
Griffin, Frank K.,Paterson, Duncan E.,Taylor, Richard J. K.
, p. 2939 - 2942 (2007/10/03)
Readily available S-glycoside dioxides were utilized in a Ramberg- Backlund rearrangement for the construction of C-linked disaccharides. This approach is ideally suited to analogue synthesis simply by variation of the alkylating agent, and is illustrated
Convergent preparation of 1,6-linked C-disaccharides via olefin metathesis
Postema, Maarten H. D.,Calimente, Daniel
, p. 4755 - 4759 (2007/10/03)
The DCC mediated coupling reaction of 3,4,6-tri-O-benzyl-1,2-dideoxy-D- arabino-hex-1-enitol (5a) with a variety of sugar based carboxylic acids 6a- d gave esters 7a-d in good yield. Methylenation of the formed esters led to the acyclic enol ethers 8a-d a
Synthesis of α- and β-D-(1→6)-C-Disaccharides by Wittig Olefination of Formyl C-Glycosides with Glycopyranose 6-Phosphoranes
Dondoni, Alessandro,Zuurmond, Helene M.,Boscarato, Alessia
, p. 8114 - 8124 (2007/10/03)
The synthesis of (1→6)-C-disaccharides by Wittig condensation of formyl C-glycofuranosides and pyranosides with galacto- and glucopyranose 6-phosphoranes is described herein. The method involves the coupling of the sugar aldehydes with the ylides and the reduction of the double bond of the resulting sugar alkenes, in most of the cases by catalytic hydrogenation. The reduction with nickel boride or diimide is employed in some special cases. O-Benzyl protective groups are removed by catalytic hydrogenation either in the course of the reduction of the double bond or in a subsequent step, while O-isopropylidene groups are cleaved by treatment with Amberlite IR-120. In this way, eight free β-D-(1→6)-C-disaccharides have been prepared in 26-61% overall yield starting from β-linked formyl C-glycosides. These include C-linked analogues of the biologically active disaccharides allolactose (Galβ1,6Glc), gentiobiose (Glcβ1,6Glc), and N-acetylamino disaccharides (GalNHAcβ1,6Gal and GalNHAcβ1,6Glc). Moreover, the synthesis of two α-D-(1→6)-C-disaccharides is described from formyl C-furanosides. The limiting condition of the synthesis of these stereoisomers is the configurational instability of the α-linked formyl C-glycosides under the basic conditions of the Wittig olefination.
The First Synthesis of a 'C-Disaccharide'
Rouzaud, Dominique,Sinay, Pierre
, p. 1353 - 1354 (2007/10/02)
Condensation of 2,3,4,6-tetrabenzylglucopyranolactone with the anion of methyl 6,7-dideoxy-2,3,4-tri-O-benzyl-α-D-gluco-hept-6-ynopyranoside followed by triethylsilane reduction provided, after hydrogenolysis, the first example of a synthetic β(1 -> 6')-'
