Scheme 8.
Reagents and conditions: (a) R3NH2, dimethyl sulfoxide (DMSO), 60 °C, 12 h; (b) Fmoc-AA-OH, HCTU/DIPEA, DMF, 4 h; (c) 20% piperidine, DMF, RT, 10 min; (d) 41, DIC/HOBt, DMF, 3 h; (e) HCOOH, 18 h.
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.