Fig. 4.
Reagents and conditions used in the synthesis of XXI–XXIII derivatives: (a) dioxane, pyridine, HoBt, DCC, 1 h at 0°C, 6 h at rt; (b) amino acid, N-ethylmorphaline, 12 h at rt.
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.