Dimeric Proanthocyanidins from the Roots of Ephedra sinica

Abstract

Two new dimeric proanthocyanidins, ephedrannin B (2) and mahuannin E (4), along with two known congeners, ephedrannin A (1) and mahuannin D (3), were isolated from the roots of Ephedra sinica Stapf. Based on NMR, MS, and CD analysis, the structures of the new compounds were deduced to be 5,7,4′-trihydroxyflavan-[4(α)→8,2(α)→O→7]-kaempferol (2) and 5,7,4′-trihydroxyflavan-[4(β)→8,2(β)→O→7]-epi-afzelechin (4). The compounds 1 – 4 were evaluated for cytotoxicity against three tumor cell lines (SGC-7901, HepG2, and HeLa), and 2 was found to be significantly active.

Key words

Ephedra sinica Stapf - Ephedraceae - proanthocyanidins - ephedrannin B - mahuannin E - cytotoxicity

References

• 1 Ding L, Shi S, Cui J, Wang S, Wang Z. Advances in research of chemical constituents and pharmacological activities of Ephedra. .  Zhong Guo Zhong Yao Za Zhi. 2006;  31 1661-4
• 2 Hikino H, Takahashi M, Konno C. Structure of ephedrannin A, a hypotensive principle of Ephedra roots.  Tetrahedron Lett. 1982;  23 673-6
• 3 Tamada M, Endo K, Hikino H, Kabuto C. Structure of ephedradine A, a hypotensive principle of Ephedra roots. Tetrahedron Lett 1979: 873-6
• 4 Tamada M, Endo K, Hikino H. Structure of ephedradine B, a hypotensive principle of Ephedra roots.  Heterocycles. 1979;  12 783-9
• 5 Konno C, Tamada M, Endo K, Hikino H. Structure of ephedradine C, a hypotensive principle of Ephedra roots.  Heterocycles. 1980;  14 295-8
• 6 Hikino H, Ogata M, Konno C. Structure of ephedradine D, a hypotensive principle of Ephedra roots.  Heterocycles. 1982;  17 155-8
• 7 Hikino H, Ogata K, Konno C, Sato S. Hypotensive actions of ephedradines, macrocyclic spermine alkaloids of Ephedra roots.  Planta Med. 1983;  48 290-3
• 8 Hikino H, Ogata M, Konno C. Structure of feruloylhistamine, a hypotensive principle of Ephedra roots.  Planta Med. 1983;  48 108-10
• 9 Hikino H, Koso Y, Ogata M, Konno C, Aisaka K, Kubota H. et al . Pharmacological actions of analogues of feruloylhistamine, an imidazole alkaloid of Ephedra roots.  Planta Med. 1984;  50 478-80
• 10 Tamada M, Endo K, Hikino H. Maokonine, hypertensive principle of Ephedra roots.  Planta Med. 1978;  34 291-3
• 11 Hikino H, Shimoyama N, Kasahara Y, Takahashi M, Konno C. Structures of mahuannin A and B, hypotensive principles of Ephedra roots.  Heterocycles. 1982;  19 1381-4
• 12 Kasahara Y, Shinomiya N, Konno C, Hikino H. Structure of mahuannin C, a hypotensive principle of Ephedra roots.  Heterocycles. 1983;  20 1741-4
• 13 Kasahara Y, Hikino H. Structure of mahuannin D, a hypotensive principle of Ephedra roots.  Heterocycles. 1983;  20 1953-6
• 14 Rawat M SM, Prasad D, Joshi R K, Pant G. Proanthocyanidins from Prunus armeniaca roots.  Phytochemistry. 1999;  50 321-4