Cardiac glycosides from Streblus asper with potential antiviral activity.

Ten undescribed cardiac glycosides, strasperosides A-J, together with twelve known analogues, were isolated from Streblus asper Lour. Their structures were elucidated on the basis of spectroscopic analysis, electronic circular dichroism data, and chemical methods. These cardiac glycosides showed diversity in steroid skeleton and sugar moiety.

Dimeric sesquiterpenoids and anti-inflammatory constituents of Sarcandra glabra.

Three novel dimeric sesquiterpenoids named sarglanoids A-C (1-3), two undescribed monomeric sesquiterpenoids named sarglanoids D (4) and E (5), and seven known compounds (6-12), were isolated and characterized from Sarcandra glabra. Compound 1 represents the first heterodimeric sesquiterpenoid composed of a eudesmane and an eremophilane moiety. Compound 2 possesses two eremophilane monomers featuring an undescribed dimerization pattern.

Dimeric clerodane diterpenoids and antiviral constituents of Dodonaea viscosa.

Three unprecedented dimeric clerodane diterpenoids, dodovisdimers A-C (1-3), along with six known clerodane monomers (4-9), were isolated from Dodonaea viscosa. Compounds 1-3 may be biosynthetically formed via an intermolecular Diels-Alder [4+2] cycloaddition between the coexisting monomers 4-7. The structures of these clerodanes were characterized by spectroscopic techniques, X-ray crystallographic study, and ECD calculations.