Practical synthesis of deoxymannojirimycin and mannonolactam from L-gulonolactone.

Synthesis of 1-Deoxy-L-rhamnojirimycin and Its Inhibitory Action against α-L-Rhamnosidase

“…NMR spectra eH at 90 MHz and 13C at 24.5 MHz) were recorded with a Hitachi R-90H spectrometer, using tetramethylsilane as an internal standard for solutions in CDC1 3 or dimethyl sulfoxide-d 6 (DMSO-d 6 ). The IR spectrum was obtained with a Hitachi 270-50 infrared spectrophotometer, the following abbreviations being used in the IR data: strong, s; medium, m; weak, w. Microanalyses were performed by the Microanalytical Laboratory of the School of Pharmaceutical Sciences at this university.…”

“…After filtering through a bed of Celite, the filtrate was concentrated, and the residue was chroma tographed in a column of silica gel. Elution, first with ethyl acetate and then with ethyl acetate-methanol (5: 1) gave 9 (5.3 g, 80% 30 (3H, d, J=6Hz, CH 3 ), 1.36, 1.46 (each s, 3H, 2CH 3 ), 3.10 (tH, OH), 3.16-3.50 (2H, m, H-4, 5), 4.23 (tH, t, J=7Hz, H-3), 6.60 (tH, br.s, NH). (10).…”

“…The residual syrup was evaporated three times with toluene in order to remove all traces of pyridine, and then chromatographed in a column of silica gel (400 g). Elution, first with chloroform and then with 6: 1 v/v chloroform-acetone, gave 5 (6). To a solution of 5 (8 g) in ethyl acetate (150 ml) and triethyl amine (4.5 ml), palladium (10%) on carbon (3 g) was added, and the mixture was stirred under hydrogen until the calculated amount of hydrogen had been absorbed.…”

“…It has recently been reported by Fleet et al 6 ) that sugar lactones had considerable potential for a short-sequence preparation of polyhydroxylated piperidines and piperidones. Therefore, the present study was designed to synthesize 3 from o-gulono-l,4-lactone by an analogous procedure to that reported by Fleet et al 6 ) 2,3-0-Isopropylidene-o-gulono-l,4-lactone (4), which could be readily prepared from commercially available o-gulono-I,4-lactone, was treated 7 ) with carbon tetra bromide and triphenylphosphine to afford 6-bromo-6-deoxy-2,3-0-isopropylidene-o-gulono-l,4-lactone (5). Hydrogenolysis of5 in the presence of palladium on carbon and triethylamine gave 6-deoxy-2,3-0-isopropylidene-o-gulono-l,4-lactone (6).…”

“…Therefore, the present study was designed to synthesize 3 from o-gulono-l,4-lactone by an analogous procedure to that reported by Fleet et al 6 ) 2,3-0-Isopropylidene-o-gulono-l,4-lactone (4), which could be readily prepared from commercially available o-gulono-I,4-lactone, was treated 7 ) with carbon tetra bromide and triphenylphosphine to afford 6-bromo-6-deoxy-2,3-0-isopropylidene-o-gulono-l,4-lactone (5). Hydrogenolysis of5 in the presence of palladium on carbon and triethylamine gave 6-deoxy-2,3-0-isopropylidene-o-gulono-l,4-lactone (6). Esterification of the remaining free hydroxyl group in 6 with trifiuoromethanesulfonic anhydride and pyridine gave 6-deoxy-2,3-0-isopropylidene-5-0-triftuoromethanesulfonyl-o-gulono-l,4-lactone (7), which, when reacted with sodium azide in DMF, afforded the inverted azidolactone (8) via an SN2 pathway.…”