Five new C21 steroidal glycosides from Periploca sepium

Five new C21 steroidal glycosides, named periseosides A–E (1–5), along with six known analogues, were isolated from the root barks of Periploca sepium. Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence. All compounds were evaluated for their immunosuppressive activities.

Research highlights▶ Five new C21 steroidal glycosides were isolated from the root barks of Periploca sepium. ▶ In vitro inhibitory effects of all compounds on Con A-stimulated splenocyte proliferation were evaluated. ▶ Compounds 3, 9 and 10 exhibited moderate inhibitory activities.