. 2023 Dec 26;29(1):155. doi: 10.3390/molecules29010155
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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Scheme 22.
Chemical structures of spiropyrans 72–80.