10.1021/acs.orglett.7b01863.s001 Junfei Zhou Junfei Zhou Guanqun Zhan Guanqun Zhan Hanqi Zhang Hanqi Zhang Qihua Zhang Qihua Zhang Ying Li Ying Li Yongbo Xue Yongbo Xue Guangmin Yao Guangmin Yao Rhodomollanol A, a Highly Oxygenated Diterpenoid with a 5/7/5/5 Tetracyclic Carbon Skeleton from the Leaves of <i>Rhododendron molle</i> American Chemical Society 2017 Compound 1 ci 1B Rhododendron molle XXXI PTP diterpenoid tran single-crystal X-ray diffraction 2017-07-13 12:23:07 Journal contribution https://acs.figshare.com/articles/journal_contribution/Rhodomollanol_A_a_Highly_Oxygenated_Diterpenoid_with_a_5_7_5_5_Tetracyclic_Carbon_Skeleton_from_the_Leaves_of_i_Rhododendron_molle_i_/5203567 A novel diterpenoid with an unprecedented carbon skeleton, rhodomollanol A (<b>1</b>), and a new grayanane diterpenoid, rhodomollein XXXI (<b>2</b>), were isolated from the leaves of <i>Rhododendron molle</i>. Their structures were elucidated using comprehensive spectroscopic methods and single-crystal X-ray diffraction. Compound <b>1</b> possesses a unique <i>cis</i>/<i>trans</i>/<i>trans</i>/<i>cis</i>/<i>cis</i>-fused 3/5/7/5/5/5 hexacyclic ring system featuring a rare 7-oxabicyclo[4.2.1]­nonane core decorated with three cyclopentane units. The plausible biosynthetic pathway for <b>1</b> was proposed. Compound <b>1</b> exhibited moderate PTP1B inhibitory activity.