Indian Forest Service (Mains), Chemistry optional · 2023 · Paper II
Q7(f). Sanger determination of the N terminus
Question
Give the mechanism for N-terminal amino-acid detection using Sanger reagent.
Answer in brief
1-Fluoro-2,4-dinitrobenzene labels the free N-terminal amino group by SNAr; complete hydrolysis then releases the identifiable DNP-amino acid.
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CoversSanger reagentFDNBN-terminal analysisSNAr mechanismDNP-amino acid
All parts of Question 7
- 7(a) Photochemistry of a rigid aryl ketone5 marks
- 7(b) Sequential anionic polymerization5 marks
- 7(c) Neoprene and chloroprene5 marks
- 7(d) Why polymers have average molar masses5 marks
- 7(e) Two unsaturated ester isomers5 marks
- 7(f) Sanger determination of the N terminus5 marks
- 7(g) Chemical-shift separation in Hz5 marks
- 7(h) Hydration of phenylacetylene5 marks