CYCLIZATION OF D-XYLO-HEXOS-5-ULOSE A CHEMICAL SYNTHESIS OF SCYLLO-INOSITOLS AND MYO-INOSITOLS FROM D-GLUCOSE

The recently described 3-O-benzyl-1,2-O-isopropylidene-α-D-xylo-hexofuranos-5-ulose (1) serves as a convenient precursor for the preparation of D-xylo-hexos-5-ulose (3). While dicarbonyl sugar 3 was obtained only in amorphous form, its structure was confirmed through reduction to D-glucitol and L-iditol. On treatment with dilute alkali, 3 readily undergoes an intramolecular aldol condensation to give 2,4,6/3,5-pentahydroxycyclohexanone (6, myo-inosose-2). The identity of 6 was confirmed through its reduction to a mixture of scyllo-and myo-inositols (7 and 8). Chromatographic evidence indicates that dilute alkali converts 6 in part into DL-2,3,5/4,6-pentahydroxycyclohexanone (9 and 10). The conversion of 3 into 6 constitutes a step in the chemical synthesis of myo-inositol from D-glucose-the second such synthesis to be reported. The cyclization of 3 to 6 closely resembles a step in a postulated biosynthesis of 8. © 1969, American Chemical Society. All rights reserved.