Mannose differs from glucose in configuration at C-2. All hydroxyl groups are equatorial in-D-glucopyranose; the hydroxyl at C-2 is axial in -D-mannopyranose.(c)The conformational depiction of-L-mannopyranose begins in the same way as that of-D-mannopyranose.L-Mannose is the mirror image ofD-mannose.To rewrite the eclipsed conformation of L-mannose in a way that permits hemiacetal forma-tion between the carbonyl group and the C-5 hydroxyl, C-5 is rotated 120°in the clockwisesense.Translating the Haworth formula into a proper conformational depiction requires that a choicebe made between the two chair conformations shown.(d)The Fischer projection formula for L-ribose is the mirror image of that for D-ribose.CHOCH2OHHHHOHOHOHd-RiboseCHOCH2OHHOHOHOHHHl-RiboseEclipsed conformation of l-ribose is
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