Skip to main content
. 2017 Nov 23;39(3):492–498. doi: 10.1038/aps.2017.119

Figure 1.

Figure 1

Chemical structure of compounds. (A) Structure of naturally occurring pentacyclic triterpenes (compounds 1–13) and ursolic acid derivatives (compounds 14–15). (B) The numbering system of the chemical structure of compound 1 (ursolic acid).