Synthesis and Structural Analysis of 5-Deoxy-5-C-(hydroxyphosphinyl)-D-xylo- and -glucopyranoses

Treatment of 3-O-acetyl-5-deoxy-5-C-(diethoxyphosphinyl)-1,2-O-isopropylidene-α-D-xylofuranose (1c) with sodium dihydrobis(methoxyethoxy)aluminate, followed by the action of mineral acid and hydrogen peroxide, gave 5-deoxy-5-C-(hydroxyphosphinyl)-D-xylopyranose (4a). The 3-O-benzyl derivative 4c was similarly obtained from the corresponding 3-O-benzyl-α-D-xylofuranose lb. Diazotization of 3-O-acetyl-6-amino-5,6-dideoxy-5-C-(dimethoxyphosphinyl)-1,2-O-isopropylidene-α-D-glucofuranose (12), followed by hydrolysis and then treatment with chlorotriphenylmethane in pyridine, afforded the corresponding 5-deoxy-6-O-triphenylmethyl derivative 17. Similar ring enlargement of 17 exclusively yielded 5-deoxy-5-C-(hydroxyphosphinyl)-D-glucopyranose. The structures of these phosphorus sugar analogues were established on the basis of mass and 400-MHz₁H NMR spectra of the per-O-acetyl-5-deoxy-5-C-(methoxyphosphinyl) derivatives 6–9 and 21–25.