Five new compounds from the stems of Ephedra equisetina.

Five new compounds were identified from the stems of Ephedra equisetina Bunge. Their structures were elucidated by spectroscopic methods, involving UV, IR, NMR spectrum and HRESIMS analyses. The absolute configuration of compound 2 was proved by comparing their experimental and calculated ECD spectrum. The vitro bioactive assay of all compounds suggested that compound 1 , 3 , 4 , 5 and 6 may have potential anti-asthmatic activities. five undescribed compounds were isolated from the stems of E. equisetina and assessed for its antiasthma activities. [Display omitted] • Five compounds were isolated from the stems of E. equisetina. • Their structures were elucidated by NMR and mass spectrometry. • The absolute configurations were deduced by interpretation of ECD. • The antiasthma activities of all the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]