Carbohydrate ppt

1.cyclic structure of D-glucose

2.Mutarotation

3.Hemeacetal

4.Acetal form of glucose

5.Ring size determination

1. Presentation on Carbohydrate Presented by :- 1.S. Moshiur Rahman 2.Asraful Islam Rayhan 3.Trina Mitra 4.Amit Kumar 5.Shaharul Islam 6.Shorrowar Azom Dept. of Pharmacy JESSORE UNIVERSITY OF SCIENCE & TECHNOLOGY

2. Out line….. 1.cyclic structure of D-glucose 2.Mutarotation 3.Hemeacetal 4.Acetal form of glucose 5.Ring size determination

3. What is Carbohydrate???

4. Definition Carbohydrates are the organic molecules that are composed of elements carbon , hydrogen and oxygen. Carbohydrates have the general formula Cx(H 2 O)y . Examples:- Glucose , Fructose etc.

5. What is Glucose??

6. Glucose is a sugar with the molecular formula C 6 H 12 O 6 . It is also known as dextrose or grape sugar. With 6 carbon atoms , it is classed as a hexose , a sub-category of monosaccharides .

7. Glucose ( An aldohexose )

8. Properties of Glucose

9. Physical properties Glucose is colorless & odorless. White crystalline solid. Melting point 146 Glucose is :- - Soluble in water. - Sparingly soluble in alcohols. - Insoluble in ether. Aqueous solution of glucose is dextrorotatory .  

10. Chemical Properties of Glucose Action as a Reducing Agent :-

11. Reaction with Hydrogen Cyanide :-

12. Cyclic Structure of D-glucose

13. Cyclic Structure of D-glucose

14. Hemiacetal ???

15. Hemiacetal:- Any of a class of compounds derived from aldehydes by adding an alcohol to the carbonyl group.

16. Example of Hemiacetal

17. Acetal form of Glucose

18. The acetal (or ketal) of a sugar is called a glycoside

19. Acetal form of Glucose

20. Mutarotation

21. Mutarotation :- Mutarotationis the change in the optical rotation because of the change in the equilibrium between two anomers , when the corresponding stereocenters interconvert.

22. Optically active compound

23. Cyclic sugars show mutarotation as α and β Anomeric forms interconvert

24. anomer anomer The specific rotation of pure a -D-glucose or b -D-glucose changes over time to reach an equilibrium ( mutarotation )

25. Fig:- Equilibrium mutarotation of -D glucose & -D glucose  

26. R ing size determination. We can methylate the various OH groups, converting them into OMe . Two kinds of OH OH at anomeric carbon OH on backbone One of the backbone OH groups may be bonded to the anomeric carbon to form a ring. We seek to detect which one. First review characteristics of hemiacetals and acetals .

27. Ring sizes (furanose or pyranose) have been determined using alkylation as a key step. CH 2 O CH 3 H O H O CH 3 H H CH 3 O H O CH 3 CH O This carbon has O H instead of O CH 3 . Therefore,its O was the oxygen in the ring.

28. Conformation of the pyranose ring. Ring flips can occur. Generally the conformation with large groups equatorial dominate. Generally the CH 2 OH should be made equatorial

29. Determination of Ring Size The size of the ring can be determined from the structure of the open-chain form.