MSc Chemistry (Organic and Analytical) SEM III Jan 2018-19 CHEMISTRY ORGANIC CHEMISTRY NATUREAL PRODUCTS AND SPECTROSCOPY Question Paper - Mumbai University | munotes

Questions asked in this paper

• Please check whether you have got the right question paper
• (2) Figures to the right indicate full marks

1. Q1 A. Attempt any two of the following: 8 marks
   • a. Explain structural features and applications of
   • i) Starch Heparin
   • b. Explain Wohl degradation studies in structural determination of lactose
   • c. Draw the structure of How will you prove the presence of following in structure of
   • d. Give the synthesis of cyanin chloride
   • B. Attempt any one of the following: 4
   • a. synthesis of Bombykol from acetylene
   • b. Give synthesis of
   • ii) Draw the structure of morphine and atropine <A. Attempt any two of the following: 8
   • a. How is longifolene synthesized form
   • b. How is phloroglucinol converted to 4,6-dimethyl benzofuranone? Draw the structure of 4-demethoxydaunomycin
   • c. What are lipids? Give its classification with suitable example
   • d. How is decalinedione prepared from resorcinol? Draw the configuration of the two enantiomers of Griseofulvin
   • A. Attempt any one of the following: 4
   • a. Write the structure of reserpine. Give the biological importance of
   • b. Write the synthesis of Triacontanol Paper Subject Code: 74796 Chemistry: Organic Chemistry Natural Products And Spectroscopy (R-2018-19)
2. Q3 <A. Attempt any two of the following: 8 marks
   • a. Using spin system notation, designate the type of spin system in the (iv)
   • b. Explain the term double resonance in NMR spectroscopy. Discuss its use in simplifying the complex NMR spectra
   • c. Calculate chemical shifts for all the aromatic carbons using incremental shifts of all the aromatic carbon atoms from the table given below for the following compounds:
   • (1) m-chloroaniline o-bromophenol
   • d. Explain long range coupling in allylic compounds and hetero aromatic
3. Q3 B. Attempt any one of the following: 4 marks
   • a. Explain the following statements:
   • (i)At the 'HNMR spectrum of N,N-dimethylformamide shows
   • (ii)At 'HNMR spectrum of methyl alcohol shows one doublet and
   • b. The following chemical shifts were observed in 'HNMR spectrum of 2,4 Match the chemical shifts with appropriate protons and justify your State whether the spectrum is First order or Second order Paper Subject Code: 74796 Chemistry: Organic Chemistry Natural Products And Spectroscopy (R-2018-19)
4. Q4 A. Attempt any two of the following: 8 marks
   • a. What is DEPT technique? Explain with suitable example how is it used to determine the number of attached hydrogens in an organic compound
   • b. Sketch and explain COSY spectrum of 3-methyl-2-butanone
   • c. What is NOE? What is its significance? Explain with suitable example
   • d. having molecular formula shows following spectral UV spectrum: no absorption above 205 nm The peak at 161 appears positive peak in DEPT-90 spectrum Assign suitable structure to the compound
5. Q4 Attempt any one of the following: 4 marks
   • a. Explain NOESY technique with suitable example
   • b. Determine the structure of a compound with molecular formula The IR , DEPT, COSY and HETCOR spectra are Paper Subject Code: 74796 Chemistry: Or ganic Chemistry Natural Products And Spectroscopy (R-2018-19) Paper Subject Code: 74796 Chemistry: Organic Chemistry Natural Products And Spectroscopy (R-2018-19)
6. Q5 Answer any four of the following: 12 marks
   • a. 1) Write a note on Amino sugars Draw the structure of Ubiquinone
   • b. i) Explain Alarm pheromones
   • ii) Write any two biological importance of porphyrins
   • c. What are insect growth regulator? Discuss the structure features of
   • d. Draw the structure of Texol. Give the applications of JH2 and JH3
   • e. How many signals you expect in the proton decoupled spectra of
   • f. the columns:
7. Q1 homotopic Paper Subject Code: 74796 Chemistry: Organic Chemistry Natural Products And Spectroscopy (R-2018-19)
   • g. State whether the following statements are true or false, justify your
   • h. the correct option:
   • (i) In the compound OH the methyl triplet CH3(d) at 6 0.9 ppm correlates NMR signal at 6 ppm in its
   • (ii) In the compound 2 4 8 C-3 carbon will be detected only in Spectrum
   • a) FTIR b) COSY (III) In the compound 4 protons give a signal at 6 2.5 ppm. It correlates with NMR signal at 6 ppm in its

Read from the scan above, so a character or two may differ. The scan is the original.