. 2020 Apr 28;25(9):2063. doi: 10.3390/molecules25092063
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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 (http://creativecommons.org/licenses/by/4.0/).
Scheme 2.
Synthetic routes to coumarins 1, 2, 4–6 and 8.