Figure 2.
(a) Key NOESY correlations of compound 1; (b) 1H–1H COSY and key HMBC correlations of compound 4; (c) Key NOESY correlations of compound 4.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.