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1. This question is about the chemistry of sugars e.g. glucose,which naturally exists as a mixture of the a and Bß forms,64% and 36% respectively. a. What is the stereochemical

relationship between these two molecules? (1 mark) b. Such mixtures can be represented by using a wavy bond at the carbon centre (s) in question:HO Cl is referred to as the anomeric carbon. On treating glucose with HBr, only the anomeric carbon is brominated, and none of the others. The main reason for this is that the intermediate formed can be stabilized by a particular means. Propose the mechanism for this bromination reaction, and below it show how the intermediate is stabilized by drawing structures. (8 marks) c. Is the product ratio maintained at 64:36 a:B? Or has it changed? If it has changed, what is the new ratio and why?(3 marks) d. Glycosylation is a chemical process of substituting the anomeric position with some other molecule, starting from the bromide e.g. Propose a reasonable synthesis of the molecule below,indicate all relevant reaction condition(s), and show the mechanism for the process: (4 marks)

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