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Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
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Thio-NHS esters are non-innocent protein acylating reagents
Weibing Liu1,2, Aziz Khan1,3, Yana Demyanenko1
1The Rosalind Franklin Institute, Harwell Oxfordshire, UK.
Nature Communications
|July 2, 2025
Summary
N-Hydroxysuccinimide (NHS) esters, vital for bioconjugation, can undergo ring-opening side reactions. This unintended modification, forming unstable N-succinamide derivatives, impacts antibody-drug conjugates and structural analyses.
Area of Science:
- Chemical Biology
- Biochemistry
- Organic Chemistry
Background:
- N-Hydroxysuccinimide (NHS) esters are crucial reagents in bioconjugation.
- Their utility depends on selective reaction of the activated acyl group over the imidic acyl moiety.
Purpose of the Study:
- To investigate potential side reactions of NHS esters.
- To understand the chemoselectivity of NHS esters in complex biological systems.
Main Methods:
- Systematic structural modification of NHS esters to alter reactivity.
- Ultra-rapid screening using tandem mass spectrometry to detect unknown modifications.
- Lysine profiling in complex proteomes.
Main Results:
- Ring-opening of NHS esters to form N-succinamide derivatives is a significant side reaction.
- The extent of this side reaction is site-dependent and can occur on the same protein substrate.
- Unintended, unstable linkages are formed in bioconjugates.
Conclusions:
- The chemoselectivity of NHS esters is not absolute.
- Re-evaluation of commercial NHS ester reagents is warranted.
- Previous conclusions drawn from NHS ester applications may need reconsideration.
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