A new diterpenoid from the leaves of Phyllanthus acidus

A new diterpenoid, phyllane C (1), along with three known compounds, ovoideal E (2), spruceanol (3), and fluacinoid B (4) were isolated from the leaves of Phyllanthus acidus growing in Thailand. The structures were determined by analysis of their MS and NMR data as well as by comparison with literature values. DFT-NMR chemical shift calculations and subsequent DP4/DP4+ probability methods were applied to define the relative configuration of 1. Compound 3 showed a weak cytotoxicity against K562 cell line (IC₅₀ 41.9 ± 2.31 µg/mL).