[Norovirus]

Good afternoon,

In chemical peptide synthesis, I read that DCC serves to "activate" the free carboxylic acid by converting it to a good ester-type leaving group. The free amine of the next amino acid attacks the activated carboxyl group to form an amide bond.

I recently came across the use of racemization-suppressing reagents like HOBt and K-Oxyma during amide bond formation involving DCC between two amino acids.

How exactly does HOBt and K-Oxyma suppress racemization?

Does it have something to do with forming a less reactive ester compared to the one generated when DCC is used?

Thank you for taking the time to read my post.

[orgopete]

How exactly does HOBt and K-Oxyma suppress racemization?

Does it have something to do with forming a less reactive ester compared to the one generated when DCC is used?

That's how I see it. The alpha hydrogens of an acid chloride are notoriously easy to lead to racemization. I'm expecting everything else is an attempt to balance reactivity vs racemization.