Three New Diterpenoids From Phyllanthus emblica Roots: Structure and Anti‐HIV Activity

Abstract

ABSTRACT Three undescribed aromatic diterpenoids ( 1–3 ), were isolated from the roots of Phyllanthus emblica and structurally characterized. Compounds 1 and 2 are cleistanthane‐type diterpenoids, and the latter possesses a rare 4,5‐ seco ‐20(10→5)‐ abeo ‐ ent ‐cleistanthane scaffold with an acetenyl at C‐14. Compound 3 was elucidated as a new podocarpane trinorditerpenoid. The structural elucidation, including absolute configuration determination, was achieved through comprehensive spectroscopic analysis (nuclear magnetic resonance, mass spectrometry, ultraviolet, and infrared) combined with time‐dependent density functional theory‐based electronic circular dichroism calculations. Compound 2 showed potential activity against HIV‐1 Bal PsV infection with an IC 50 value of 3.30 µM.