User:Benjah-bmm27/degree/3/MCG
Important functions and applications
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Hemiacetals and mutarotation
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- Hemiacetal formation
- alcohol + aldehyde → hemiacetal
- acid promotes forward reaction, base promotes reverse
- new chiral centre formed
- In monosaccharides, the new chiral centre is called the anomeric carbon
- Mutarotation of hemiacetals
- α and β anomers of monosaccharides interconvert
- α hemiacetal → aldehyde + alcohol → β hemiacetal
- In solution, glucose is:
- 36 % α-D-glucopyranose
- 63 % β-D-glucopyranose
- 0.003 % open chain aldehyde
- negligible proportions exist as α-D-glucofuranose and β-D-glucofuranose
- For glucose, 4C1 conformation preferred to 1C4 as the former has all equatorial groups, latter has all axial
Glycosylation reactions
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