. 2015 Dec 17;20(12):22565–22577. doi: 10.3390/molecules201219856
© 2015 by the authors.
Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons by Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
Figure 1.
Chemical structure of compounds 1–7.