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New Pimarane-Type Diterpenoid and ent-Eudesmane-Type Sesquiterpenoid from Bornean Liverwort Mastigophora diclados

Shean-Yeaw Ng , Takashi Kamada and Charles S. Vairappan

Laboratory of Natural Products Chemistry, Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia

Abstract: Three populations of Mastigophora diclados were collected from Mount Kinabalu, Mount Alab, and Mount Trus Madi. Each population yielded a total of four, four, and five secondary metabolites, respectively. A new compound, dicladoic acid (1) and the enantiomer of the known chlorantene G (8), along with six known compounds (2-7) were isolated from the MeOH extract of Bornean liverwort Mastigophora diclados. The structures of the novel metabolites were established by analyses of the spectroscopic data, including 1D NMR, 2D NMR, HRESIMS and IR. Isolated compounds shed some light into the chemosystematics of secondary metabolites in M. diclados. Herbertane-type sesquiterpenes were identified as the major metabolites in all three populations in Sabah and could be regarded as a suitable chemotaxonomical marker.

Keywords: Pimarane; diterpenoid; Mastigophora diclados; liverwort; Borneo island. © 2017 ACG Publications. All rights reserved.