Caseatardies A-K, eleven undescribed clerodane diterpenoids isolated from Casearia tardieuae and their anti-inflammatory activity.

A phytochemical investigation to obtain bioactive substances as lead compounds or agents for anti-inflammatory led to the obtainment of eleven previously undescribed clerodane diterpenoids, named caseatardies A-K (1 − 11), and four known clerodane diterpenoids (12 – 15) from the twigs and leaves of Casearia tardieuae. The structural elucidation of these clerodane diterpenoids was based on 1D and 2D-NMR spectroscopy (COSY, HSQC, HMBC and ROESY) as well as high resolution mass spectrometry (HR-ESI-MS). The relative configurations were defined by ROESY correlations. The anti-inflammatory activity of all the isolated compounds was screened and compound 15 decreased LDH level in a dose-dependent manner, showing IC 50 value of 2.89 μM. [Display omitted] • Eleven new clerodane diterpenoids with conjugated diene side chain at C-9 were isolated from Casearia tardieuae. • The compound 15 showed potent inhibitory activity against pyroptosis by blocking NLRP3 inflammasome activation. • Their structures were established by elucidated by 1D, 2D-NMR and HR-ESI-MS analyses. [ABSTRACT FROM AUTHOR]