Hexose

A hexose is a monosaccharide with six carbon atoms.

Related Topics:
Monosaccharide - Carbon

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They either have an aldehyde functional group in position 1 (aldohexoses), or a ketone functional group in position 2 (ketohexoses).

Related Topics:
Aldehyde - Functional group - Ketone

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The aldohexoses have four chiral centres ("asymmetric carbon atoms") and so 16 different stereoisomers are possible. Of these, only 3 occur in nature - D-glucose, D-galactose and D-mannose. The D/L configuration is based on the orientation of the hydroxyl radical at position 3, and does not refer to the direction of optical activity.

Related Topics:
Stereoisomer - Hydroxyl - Optical activity

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The eight D-aldohexoses are:

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CH=O CH=O CH=O CH=O

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