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Updated: May 10, 2026

Dithranol as a Matrix for Matrix Assisted Laser Desorption/Ionization Imaging on a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer
Published on: November 26, 2013
Micranthanone A, a new diterpene with an unprecedented carbon skeleton from Rhododendron micranthum
Mengke Zhang1, Yan Zhu, Guanqun Zhan
1Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology , Wuhan 430030, Hubei, P. R. China, School of Chemistry and Chemical Engeering, Taishan Medical University , Tai-An 271016, Shandong, P. R. China, and Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou 350002, Fujian, P. R. China.
Abstract:
A new diterpene with an unprecedented carbon skeleton, micranthanone A (1), two new grayanane diterpenoids bearing an unusual 5,6-(3,4-dihydroxylbenzylidene acetal) motif, rhodomicranols A (2) and B (3), and three known grayanane diterpenoids (4-6) were isolated from Rhododendron micranthum. Their structures were elucidated by spectroscopic analyses, calculated ECD, and single-crystal X-ray diffraction. The in vitro immunomodulatory activities of 1-6 were evaluated, and a plausible biogenetic pathway for 1 is proposed.
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