Bisabolane‐Type Sesquiterpenoids from the Rhizomes of Glochidion coccineum

Abstract A novel bisabolane‐type sesquiterpenoid lactone, glochicoccin A ( 1 ), and three new norbisabolane sesquiterpenoids, glochicoccins B–D ( 2 – 4 ), together with two known norbisabolane sesquiterpenoids, phyllaemblic acid ( 5 ) and phyllaemblic acid methyl ester ( 6 ), were isolated from the rhizomes of Glochidion coccineum. Their structures were elucidated by different spectroscopic (IR, UV, NMR) and mass‐spectrometric (MS) techniques. The structure and relative configuration of 1 was confirmed by single‐crystal X‐ray diffraction ( Fig. 2 ). None of the compounds were found to exhibit cytotoxic or antioxidant activities.