This article refers to:
Dong-Dong Zhang, Jun Yang, Ji-Feng Luo, Xiao-Nian Li, Chun-Lin Long & Yue-Hu Wang. (2017). New aporphine alkaloids from the aerial parts of Piper semiimmersum, Journal of Asian Natural Products Research, doi: 10.1080/10286020.2017.1346630
When the above article was first published online, the structures of compounds 1 and 2 were wrongly given in figure 1 on page 2. The correct structures are given below. The authors apologize for this error and any consequent inconvenience to editors and readers.
Figure 1. Structures of compounds 1 and 2.