title: New Formyl Phloroglucinol Meroterpenoids from the Leaves of Eucalyptus robusta.
abstract: Seven new formyl phloroglucinol meroterpenoids (FPMs), namely eucalrobusones J-P (1-7), as well as three known ones (8-10) were isolated from the leaves of Eucalyptus robusta. Their structures were elucidated by spectroscopic data analysis, and their absolute configurations were determined by applications of the Snatzke's helicity rule and the electron circular dichroism (ECD) calculation. These FPMs are diverse in coupling patterns between phloroglucinol and sesquiterpenoid units, forming novel polycyclic ring systems. Compound 1 possesses a new carbon skeleton that a 1-oxaspiro[5.6]dodecane core is formed through C-14 rather than C-4 of the aromadendrane moiety. Compound 2 features a novel 6/7/5 ring-fused 6-oxabicyclo[3.2.2]nonane skeleton. Compounds 3-5 are rare aristolane-based FPMs. By forming different oxo bridges, compound 3 is the first sample of FPM with benzo-dihydrofuran structure, and compound 4 possesses a novel 6/6/6/6/3-fused pentacyclic skeleton. Compounds 1, 6, and 8 exhibited significant antifungal activities against Candida glabrata with MIC50values of 2.57, 1.95, and 2.49 μg/mL, respectively.
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, People' s Republic of China.
authors.forename: Zhi-Chun
authors.initials: ZC
authors.lastname: Shang
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, People' s Republic of China.
authors.forename: Ming-Hua
authors.initials: MH
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, People' s Republic of China.
authors.forename: Rui-Huan
authors.initials: RH
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, People' s Republic of China.
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, People' s Republic of China.
authors.forename: Ling-Yi
authors.initials: LY
authors.lastname: Kong
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D041221:Candida glabrata / Q000254:growth & development*; D005052:Eucalyptus / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D013729:Terpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D000935:Antifungal Agents; D013729:Terpenes