January 15, 2025, 03:36:18 AM
Forum Rules: Read This Before Posting


Topic: Determining the optical purity for a family of new amino acid derivatives  (Read 166 times)

0 Members and 1 Guest are viewing this topic.

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5724
  • Mole Snacks: +332/-24
A reviewer would like to know whether our novel amino acid salts RCH=CHCH2CH(NH2HCl)CO2H] racemized during the synthesis.  They are soluble in water/acetonitrile during LC-MS experiments and generally soluble in DMSO.  Only one is UV-active, which might make detection in LC more difficult.  I doubt that they would be soluble in a chiral NMR solvent, but I don't know.  What sorts of methods should we be thinking about?
EDT
One person suggested making Mosher amides.
« Last Edit: January 13, 2025, 01:07:22 PM by Babcock_Hall »

Offline rolnor

  • Chemist
  • Sr. Member
  • *
  • Posts: 2315
  • Mole Snacks: +156/-10
Yes, Mosher amide would be a good idea, chiral solvents are not reliable, you might not get any separation of the peaks on NMR, a chiral column and LC would require that you have the two isomers and develop a method with a chiral column I guess.

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5724
  • Mole Snacks: +332/-24
My concern with Mosher chemistry is that we have a free carboxylic acid in the molecule, which might react with the Mosher acyl chloride.

HPLC with a polysaccharide based stationary phase or with a chiral ion-pair reagent might work, but both of those are speculation on my part.  I am starting to search for examples.
« Last Edit: Yesterday at 10:21:25 AM by Babcock_Hall »

Sponsored Links