RESUMEN
Objective: To investigate the chemical constituents in the whole plant of Lycopodium japonicum, native to Suizhou city, Hubei province for the first time. Methods: The compounds were isolated and purified by a combination of silica gel, ODS, and Sephadex LH-20 column chromatography and prep-HPLC. Their chemical structures were established by their physicochemical properties and spectral data. Results: Eight pentacyclic triterpenoids have been isolated and characterized from the methanol extract of the whole plant, they are 21-episerratenediol (1), serratenediol (2), α-onocerin (3), serrat-14-en-3β, 21β, 24-triol (4), 3β, 21α- dihydroxyserrat-14-en-16-one (5), lycoclavanol (6), lyclaninol (7), and 3α, 21β, 24-trihydroxyserrat-14-en-16-one (8). Conclusion: Compounds 1-8 are all serretene triterpenoids, the characteristic chemical constituents in the plants of genus Lycopodium L. Compound 5 is isolated from this plant for the first time.