A Small Change in Structure, a Big Change in Flexibility †
Nikolay G. Vassilev, Ivo C. Ivanov · 2023
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Description
Nikolay Vassilev and Ivo Ivanov show how swapping one atom in a small molecule can nearly double the barrier to its internal rotation. The molecule carries amide and enamide bonds, cousins of the peptide bond that shapes proteins. How stiffly those bonds twist matters for molecular machines as well as folding.
Their 2023 study measures the barriers with dynamic NMR and checks them against density functional calculations. In their lead compound the amide barrier sits near sixteen kilocalories per mole and the enamine barrier near nineteen. In a twin where one nitrogen becomes a CH group, both barriers drop to about twelve. The calculations trace the stiffness to how the end nitrogen's lone pair pours into the neighboring bond.
Catalog record
| CREATOR | Nikolay G. Vassilev, Ivo C. Ivanov |
|---|---|
| YEAR | 2023 |
| COLLECTION | PAPERS |
| FORMAT | TXT |
| FILE SIZE | 23 KB |
| VERSION | 1.0 |
| LICENSE | CC BY 4.0 |
| RIGHTS | CC BY |
| SOURCE | Europe PMC |