- Glycosyl ortho-Methoxybenzoates: Catalytically Activated Glycosyl Donors with an Easily Removable and Recyclable Leaving Group
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We describe the β-ortho-methoxybenzoate as a shelf stable and practical C-1 nucleofuge for catalytic chemical glycosylation in which the benzoic acid by-product can be easily removed, reisolated, and potentially recycled after the glycosylation reaction. This new type of glycosyl donor can be efficiently activated by a range of promoters, including Bi(OTf)3, Fe(OTf)3, TMSOTf (TMS = trimethylsilyl), and triflic acid, with low (10 mol-%) catalyst loadings. The donor shows higher reactivity than analogous benzoate, p-methoxybenzoate and p-cyano-o-methoxybenzoate donors. In glycosylation reactions with o-methoxybenzoate donors, the yields of disaccharide products were good to excellent for various glycosyl acceptors, including a carbohydrate-based secondary alcohol. Furthermore, β-selective mannosylation was achieved with a Crich-type donor at 0 °C to ambient temperature, without donor preactivation. The donor was also used for the first step of a one-pot two-step glycosylation to obtain a trisaccharide; the second coupling involved activation of a thioglycoside with NIS/TMSOTf (NIS = N-iodosuccinimide). We believe that this offers a good alternative to current protocols.
- Kristensen, Steffan K.,Salamone, Stéphane,Rasmussen, Michelle R.,Marqvorsen, Mikkel H. S.,Jensen, Henrik H.
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- Azolylbenzamides and analogues and their use for treating osteoporosis
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A compound of formula (I) or a salt thereof, or a solvate thereof, wherein: X represents oxygen, sulphur, or NRb; Y and Z each independently represent nitrogen, CH, CR1 or CR2; A represents an unsubstituted or substituted aryl group or an unsubstituted or substituted heterocyclyl group; Ra represents —C(O)NRsRt; R1 and R2 each independently represents hydrogen or specific substituents; and the use of such a compound in the treatment and/or prophylaxis of diseases associated with over activity of osteoclasts in mammals.
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Page/Page column 10
(2010/02/10)
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- Indole derivatives and their use for the treatment of osteoporosis amongst other applications
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A compound of formula (1) or a salt thereof, or a solvate thereof, wherein; R1and R2each independently represents C1-6alkoxy or halo; R3and R4each independently represents hydrogen, C1-6alk
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Page column 16
(2010/02/08)
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- Piperazine based inhibitors of factor xa
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Novel compounds of the general formulae (I) or (II), including their pharmaceutically acceptable isomers, salts, hydrates, solvates and prodrug derivatives having activity against mammalian factor Xa are described. Compositions containing such compounds a
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- Inotropic 2-arylimidazo[1,2-a]pyrimidines
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A series of 2-arylimidazo[1,2-a]pyrimidines has been prepared and evaluated for inotropic activity. Three of these heterocycles, ether 19, sulphide 21 and mesylate 24 displayed more potent inotropic effects in vitro than isomazole. The in vivo inotropic p
- Barraclough,Black,Cambridge,Capon,Cox,Firmin,Gerskowitch,Giles,Glen,Hill,Hull,Iyer,Kettle,King,Nobbs,Randall,Skone,Smith,Vine,et al.
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p. 207 - 217
(2007/10/02)
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