. 2017 Jun 8;22(6):911. doi: 10.3390/molecules22060911
© 2017 by the authors.
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/).
Figure 3.
Chemical structures of compounds 23–25, 29–31.