University of Delhi 2008 B.Sc Chemistry organic - xv - Question Paper

Q1. (a) discuss why Fructose is a reducing sugar. Name the rearrangement involved in the process.

(b) discuss the mechanism of Mutarotation.
(c) How is the ring size of glucose determined by oxidation with HIO4. Illustrate.
(d) How glucose is converted to fructose?

Q2. (a) Draw the more stable conformation of the subsequent and justify your ans.
i. ß-L-glucopyranose
ii. a-D-glucopyranose

(b) Mutarotation is faster in 2-hydroxypyridine as compared to that in a mixture of phenol and pyridine. discuss.
(c) discuss why fructose and glucose form the identical osazone.
(d) What is invert sugar? provide it’s systematic name.

Q3. (a) describe Surfactants and how are they classified?
(b) elaborate hard and soft syndets?
(c) elaborate non-ionic surfactants? provide their importance.
(d) discuss the mechanism of cleansing action of soaps.
(e) provide synthesis of a biodegradable anionic detergent.

Q4. (a) What is isoelectronic point? provide its significance.
(b) provide the synthesis of praline using phthalamide and malonic ester.
(c) discuss Erlenmeyer azalactone synthesis.
(d) discuss secondary structure of proteins.

Q5. (a) discuss the Edman degradation method of N-terminal amino acid determination.
(b) discuss solid-phase peptide sunthesis.
(c) Name 2 amino acids not obtained in proteins.
(d) What is denaturation of proteins?

Q6. (a) elaborate essential oils? provide 2 examples.
(b) What is isoprene rule. discuss
(c) provide a synthesis of citral.
(d) Write various geometrical isomers of citral.

Q7. (a) describe Rancidity of fats and oils and how it can be prevented?
(b) elaborate drying, nondrying and semidrying oils? discuss.
(c) elaborate phospholipids and what is their importance in biological systems?
(d) How is the degree of unsaturation of fats or oils determined?

Q8. (a) How would you convert :
i. Uric acid to theobromine
ii. Uric acid to guanine

(b) explain the structure of DNA.
(c) Write a short note on Kreb cycle.

Earning:   Approval pending.