LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

WD 35

M.Sc. DEGREE EXAMINATION – CHEMISTRY

SECOND SEMESTER – April 2009

          CH 2953 / 2951- CHEMISTRY OF HETEROCYCLICS AND NATURAL PRODUCTS

 

 

 

Date & Time: 27/04/2009 / 1:00 – 4:00   Dept. No.                                                   Max. : 100 Marks

 

 

 

 

PART-A                                      

Answer ALL questions.                                                                                              (10 x 2 = 20)

 

1. Write the IUPAC name of the following compounds:

 

2. Why does the electrophilic attack of pyrimidine at C-5 preferred?
3. What are alkaloids? Give an example for alkaloid does not contain nitrogen atom in the ring.
4. Mention any two functions of morphine.
5. Explain the importance of Tilden’s reagent in the elucidation of terpenoids.
6. What are diterpenoids? How is it differentiated from monoterpenoids?
7. Write a note on: Classification of hormones.
8. Draw the structure and write any two functions of cortisone.
9. What happens when anthocyanidin is fused with hot KOH?
10. How is isoflavone synthesized?

 

 

                                                                      

                                                                       PART-B                                      

Answer ANY EIGHT questions.                                                                                 (8 x 5 = 40)

 

11. Write short notes on: Spectral properties of heterocyclic compounds.
12. Orientation in nucleophilic substitution of pyridine at the 2- or 4- position is preferred. Why? Explain.
13. Explain the acidic and basic character of azoles.
14. How are alkaloids extracted from plants? Explain.
15. Explain the structure of belladine.
16. Elucidate the structure of atropine.
17. How is zinziberene synthesized? Explain.
18. Write a note on: a) Classification of terphenes       b) General characteristics of terpenoids
19. Equatorial hydroxyl and carboxyl groups of sreroids are esterified more readily than the axial groups. Why? Explain.
20. Give the structure and any two functions of oestrone and progestrone.
21. Explain the amphoterric nature of cyanidin chloride with mechanism.
22. Discuss the structure of flavonol.

 

 

 

 

 

 

 

 

PART-C                                    

Answer ANY FOUR questions.                                                                                  (4 x 10 = 40)

 

23. a) Predict the products of the following reactions:           (5×1)
24. b) How will you synthesize coumarins? (5)
25. a) How does uric acid is formed in human body? Explain. (5)
26. b) Discuss the constitution of ecgonine. (5)
27. Elucidate the structure of Morphine.
28. Discuss the structural elucidation of camphor.
29. a) Secondary axial hydroxyl groups are more readily oxidized by chromic acid than secondary equatorial hydroxyl groups in steroids. Explain. (4)
30. b) How does the IR and UV spectra used in conformational analysis of steroids? Explain with cotton effect. (6)
31. Explain the general method to determine the structure of anthocyanidin.

 

 

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