Page 10 - phytochemistry I - PharmD Clinical

 The configuration of sugars is designated by the symbols D & L.
 Monosaccharides are designated as D & L on the basis of the configuration

of the highest numbered asymmetric carbon, D if the -OH is on the right and
L if the -OH is on the left.
 The symbols d and I or (+) and (-) are used to designate sign of rotation of
plane-polarized light.
 Monosaccharides existing in the form of heterocycles are classified with
respect to the size of the ring system i.e. 6-membered ring structures
considered to be related to pyran are called pyranoses, and the 5 -
membered ring structures related to furan are called furanoses. This type
of nomenclature can be applied to oligosaccharides and glycoside
derivatives, e.g. maltose can be named 4-D-glucopyranose-α-D-
glucopyranoside, sucrose is 1-α D-glucopyranosyl-β-D-fructofuranoside,
and lactose is 4-D- glucopyranosyl-β-D-galactopyranoside

Carbohydrates of Medicinal and Pharmaceutical Importance

 Many pharmaceutical products contain carbohydrates and their derivatives as
therapeutic agents or as pharmaceutic necessities.

Sugar alcohols

 These compounds are closely related to carbohydrates, so it is
traditional to classify them as carbohydrate derivatives, i.e. sugar
alcohols

 The hexahydroxy alcohols, sorbitol (glucitol), mannitol and galactitol
(dulcitol) are natural products widely distributed in plants, they are
reduction products of the corresponding aldohexoses, glucose,
mannose and galactose, respectively.

Sorbitol (D-glucitol)

Occurrence:
 Sorbitol is naturally abundant in many rosaceous fruits such as the ripe

berries of sorbus aucuparia (Rosaceae).
 It is prepared synthetically by the catalytic hydrogenation or by electrolytic

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