article published yes Yulong Jin author Pradeep K Mandal author 6a3def15-d4b4-11ef-9fa9-a24c1f545ec30000-0001-5996-956X Juntian Wu author Niklas Böcher author Ivan Huc author Sijbren Otto author Dynamic foldamers are synthetic folded molecules which can change their conformation in response to an external stimulus and are currently at the forefront of foldamer chemistry. However, constitutionally dynamic foldamers, which can change not only their conformation but also their molecular constitution in response to their environment, are without precedent. We now report a size- and shape-switching small dynamic covalent foldamer network which responds to changes in pH. Specifically, acidic conditions direct the oligomerization of a dipeptide-based building block into a 16-subunit macrocycle with well-defined conformation and with high selectivity. At higher pH the same building block yields another cyclic foldamer with a smaller ring size (9mer). The two foldamers readily and repeatedly interconvert upon adjustment of the pH of the solution. We have previously shown that addition of a template can direct oligomerization of the same building block to yet other rings sizes (including a 12mer and a 13mer, accompanied by a minor amount of 14mer). This brings the total number of discrete foldamers that can be accessed from a single building block to five. For a single building block system to exhibit such highly diverse structure space is unique and sets this system of foldamers apart from proteins. Furthermore, the emergence of constitutional dynamicity opens up new avenues to foldamers with adaptive behavior. American Chemical Society2023 eng 0002-7863 1520-5126 3670546910.1021/jacs.2c09325 14552822-2829 yes Y. Jin, P.K. Mandal, J. Wu, N. Böcher, I. Huc, S. Otto, Journal of the American Chemical Society 145 (2023) 2822–2829. Jin, Y., Mandal, P. K., Wu, J., Böcher, N., Huc, I., &#38; Otto, S. (2023). (Re-)directing oligomerization of a single building block into two specific dynamic covalent foldamers through pH. <i>Journal of the American Chemical Society</i>. American Chemical Society. <a href="https://doi.org/10.1021/jacs.2c09325">https://doi.org/10.1021/jacs.2c09325</a> Jin, Yulong, Pradeep K Mandal, Juntian Wu, Niklas Böcher, Ivan Huc, and Sijbren Otto. “(Re-)Directing Oligomerization of a Single Building Block into Two Specific Dynamic Covalent Foldamers through PH.” <i>Journal of the American Chemical Society</i>. American Chemical Society, 2023. <a href="https://doi.org/10.1021/jacs.2c09325">https://doi.org/10.1021/jacs.2c09325</a>. Jin Y, Mandal PK, Wu J, Böcher N, Huc I, Otto S. 2023. (Re-)directing oligomerization of a single building block into two specific dynamic covalent foldamers through pH. Journal of the American Chemical Society. 145(5), 2822–2829. Jin Y, Mandal PK, Wu J, Böcher N, Huc I, Otto S. (Re-)directing oligomerization of a single building block into two specific dynamic covalent foldamers through pH. <i>Journal of the American Chemical Society</i>. 2023;145(5):2822-2829. doi:<a href="https://doi.org/10.1021/jacs.2c09325">10.1021/jacs.2c09325</a> Jin, Yulong, et al. “(Re-)Directing Oligomerization of a Single Building Block into Two Specific Dynamic Covalent Foldamers through PH.” <i>Journal of the American Chemical Society</i>, vol. 145, no. 5, American Chemical Society, 2023, pp. 2822–29, doi:<a href="https://doi.org/10.1021/jacs.2c09325">10.1021/jacs.2c09325</a>. Y. Jin, P. K. Mandal, J. Wu, N. Böcher, I. Huc, and S. Otto, “(Re-)directing oligomerization of a single building block into two specific dynamic covalent foldamers through pH,” <i>Journal of the American Chemical Society</i>, vol. 145, no. 5. American Chemical Society, pp. 2822–2829, 2023. 209702026-01-11T14:41:26Z2026-01-20T07:15:32Z