(Solved): Question 8 a) [3 marks] 9) The structure of B-D-glucopyranose is shown below in the Haworth project ...

Question 8 a) [3 marks] 9) The structure of B-D-glucopyranose is shown below in the Haworth projection. To the right of the structure draw B-D-glucopyranose in the chair conformation [1 mark] CH,OH H -O OH H OH H OH H H OH B-D-glucopyranose Chair conformation 4) Explain why the B-form of D-glucopyranose is more stable than the o-anomeric form. You may wish to refer directly to the structure above [1 mark] iii) Draw the open chain form of D-glucose in the Fischer projection [1 mark] b) [2 marks] Carbohydrates used to be considered as only important as an energy source (e.g. starches) or as mechanical supports (e.g. cellulose), but over the last 15 years, their biological relevance has become much more recognised, including in cellular recognition processes. The wide range of functions carbohydrates possess is believed to relate to their great structural diversity. Using an aldohexose as the scaffold, describe and illustrate three structural diversity features available. Hint you may want to consider stereochemistry, hemiacetal and acetal formation. Question 8 a) [3 marks] i) The structure of B-D-glucopyranose is shown below in the Haworth projection. To the right of the structure draw B-D-glucopyranose in the chair conformation [1 mark]. CH?OH -O, OH H OH H OH H H OH B-D-glucopyranose Chair conformation ii) Explain why the B-form of D-glucopyranose is more stable than the a-anomeric form. You may wish to refer directly to the structure above [1 mark]. Draw the open chain form of D-glucose in the Fischer projection [1 mark]. iii) b) [2 marks] Carbohydrates used to be considered as only important as an energy source (e.g. starches) or as mechanical supports (e.g. cellulose), but over the last 15 years, their biological relevance has become much more recognised, including in cellular recognition processes. The wide range of functions carbohydrates possess is believed to relate to their great structural diversity. Using an aldohexose as the scaffold, describe and illustrate three structural diversity features available. Hint: you may want to consider stereochemistry, hemiacetal and acetal formation.