Hapmnioides A–C, Rearranged Labdane-Type Diterpenoids from the Chinese Liverwort <i>Haplomitrium mnioides</i>

Many exceptional labdane-type diterpenoids have been exclusively found in liverworts, which serve as taxonomic molecules or play important ecological roles in interactions among organisms. Three unprecedented labdane-type diterpenoids hapmnioides A (<b>1</b>), B (<b>2</b>), and C (<b>3</b>) formed through cascade rearrangement from the Chinese liverwort <i>Haplomitrium mnioides</i> are reported. Their structures were established by comprehensive spectroscopic analysis coupled with single-crystal X-ray diffraction, and their anti-inflammatory activities were also preliminarily tested