LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
B.Sc. DEGREE EXAMINATION – CHEMISTRY
SIXTH SEMESTER – APRIL 2011
CH 6610/CH 6604 – CHEMISTRY OF NATURAL PRODUCTS
Date : 09-04-2011 Dept. No. Max. : 100 Marks
Time : 9:00 – 12:00
PART – A
ANSWER ALL THE QUESTIONS (10×2=20 marks)
- How is N-methyl group identified in alkaloids?
- What happens when piperine is subjected to hydrolysis with NaOH?
- Mention the products of ozonolysis of geraniol.
- Draw the structure of vitamin-A. How is it structurally related with β-carotene?
- What are the uses of anthocyanidin.
- What are flavones?
- Name the products obtained when uric acid is oxidized with HNO3.
- Draw the structures of caffeine and theophylline.
- Name the chromophores and auxochromes present in alizarin and methyl orange.
- What are phthalein dyes? Give examples.
PART – B
ANSWER ANY EIGHT QUESTIONS (8×5=40 marks)
- a) What is isoprene rule? b) How are terpenes classified?
- Outline the synthesis of piperine.
- Establish the structure of coniine and give its synthesis.
- Elucidate the structure of menthol.
- a) What happens when camphor is i) oxidized and ii) reduced?
- b) Show that camphor is bicyclic. (3+2)
- Give any one synthesis of flavones.
- a) What are anthocyanins? What are the two components of anthocyanins?
- b) What happens when hirsutidin chloride is hydrolyzed with Ba(OH)2 ? (3+2)
- How is uric acid synthesized from urea?
- What are purines? Mention their biological importance.
- Discuss the structure of caffeine.
- Discuss briefly on the relationship between color and constitution of dyes on the basis of
resonance theory.
- What are azo dyes? Describe the preparation and applications of any one azo dye.
PART – C
ANSWER ANY FOUR QUESTIONS (4×10=40 marks)
- Establish the structure of nicotine and give its synthesis.
- Discuss the structure of citral and its synthesis.
- How will you arrive at the structure of quercetin?
- Outline the synthesis of oesterone.
- Explain the structure and synthesis of cyanidin hydrochloride.
- a) Explain the terms i) bathochromic shift ii) hypsochromic shift.
- b) How are the following compounds prepared? i) Alizarin ii) Indigo (4+6)