Abstract:To investigate diterpenoids from the aerial parts of Andrographis paniculata (Burm. f.) Nees, three new ent-labdane diterpenoids, namely 19-norandrographolides A–C (compounds 1–3), were isolated from the ethanolic extract of A. paniculata. Their structures were established by HRESIMS and NMR spectral data in combination with X-ray crystallographic analysis.（*Author for correspondence. Tel (Fax): +86 (0)20 8522 1559; E-mail:
chywc@yahoo.com.cn）