中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | benzyl 2,3-O-isopropylidene-β-L-xylopyranoside | 478175-66-5 | C15H20O5 | 280.321 |
—— | benzyl 4-O-(imidazol-1-ylsulfonyl)-2,3-O-isopropylidene-β-L-xylopyranoside | 478175-76-7 | C18H22N2O7S | 410.448 |
—— | benzyl β-L-xylopyranoside | 478175-99-4 | C12H16O5 | 240.256 |
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | benzyl 4-C-cyano-4-deoxy-α-D-arabinoside | 770735-90-5 | C13H15NO4 | 249.266 |
—— | benzyl 4-{[(tert-butoxycarbonyl)amino]methyl}-4-deoxy-2,3-O-isopropylidene-α-D-arabinoside | 478175-80-3 | C21H31NO6 | 393.48 |
—— | (2R,3S,4R,5R)-5-(aminomethyl)-2-phenylmethoxyoxane-3,4-diol | 1026939-30-9 | C13H19NO4 | 253.298 |
—— | benzyl 4C-[(tert-butoxycarbonyl)amino]methyl-4-deoxy-α-D-arabinopyranoside | 478175-82-5 | C18H27NO6 | 353.415 |
Improvements in the preparation of a key imidazylate and the reduction of the derived nitrile have led to more efficient syntheses of isofagomine, noeuromycin, azafagomine, and isofagomine lactam. As well, a precursor of azafagomine has been converted into azanoeuromycin, and the nitrogen atom of isofagomine has been incorporated into a guanidine residue.
Benzyl 4-cyano-4-deoxy-α-D-arabinoside was converted into both its2,3-di-O-acetyl and 2,3-di-O-(tert-butyldimethylsilyl)derivatives. The latter, by a process of hydrogenolysis, oxidation, and methanolysis, gave methyl2,3-di-O-(tert-butyldimethylsilyl)-4-cyano-4-deoxy-D-arabinonate. Reductionof this methyl ester with borane dimethyl sulfide gave, after deprotection, isofagomine lactam.
The treatment of benzyl 2,3-O-isopropylidene-β-L-xylopyranoside with N-hydroxyphthalimide under Mitsunobu conditions, followed by protecting-group interchange, gave benzyl 4-O-[(tert-butoxycarbonyl)amino]-2,3- O-isopropylidene-α-D-arabinoside. Mild acid hydrolysis and catalytic hydrogenolysis afforded 4-O-[(tert-butoxycarbonyl)amino]-D-arabinose that, upon heating in water, gave the dihydrooxazine [(4R,5S,6R)-5,6-dihydro-4,5-dihydroxy-6-hydroxymethyl-4H-1,2-oxazine] as a crystalline solid. A single-crystal structure determination of this solid showed it to exist in the 5H6 conformation. Reduction of the dihydrooxazine gave the tetrahydrooxazine [(4R,5S,6R)-4,5-dihydroxy-6-hydroxymethyl-3,4,5,6-tetrahydro-2H-1,2-oxazine]. The dihydrooxazine was an effective inhibitor of two β-glucosidases (Ki = 27 and 35 µM). Benzyl 2,3-O-isopropylidene-β-L-xylopyranoside, via the derived imidazylate, was converted into a nitrile that, upon reduction and protecting-group manipulations, gave benzyl 4-C-aminomethyl-4-deoxy-α-D-arabinoside. Treatment of this amine with hydrogen and palladium-on-carbon gave isofagomine.Key words: dihydrooxazine, tetrahydrooxazine, isofagomine, iminosugars, glycosidase inhibitors.