title: Di-nor- and 17-nor-pimaranes from Icacina trichantha.
abstract: Six new pimarane derivatives, including two di-nor-pimaranes (1, 2), two 17-nor-pimaranes (3, 4), and two 17-nor-(9β-H)-pimaranes (5, 6), were isolated from the tuber of Icacina trichantha. Their structures were elucidated based on spectroscopic and HRMS data. The absolute configurations of 1 and 5 were determined by single-crystal X-ray diffraction, and that of 2 was established by electronic circular dichroism data analysis. Compound 3 possesses a unique C-20 acetal moiety. This is the first report of the isolation of di-nor-(9β-H)-pimarane derivatives from Icacina plants. Compounds 5 and 6 showed moderate cytotoxicity against MDA-MB-435, MDA-MB-231, and OVCAR3 cell lines, with IC50 values of 2.91-7.60 and 1.48-3.23 μM, respectively.
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.
authors.forename: Brian
authors.initials: B
authors.lastname: Guo
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.|Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Abuja , Abuja 920001, Nigeria.
authors.forename: Monday M
authors.initials: MM
authors.lastname: Onakpa
authors.affiliation: Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Huang
authors.affiliation: Center for Biomolecular Sciences and Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago , Chicago, Illinois 60607, United States.
authors.forename: Bernard D
authors.initials: BD
authors.lastname: Santarsiero
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.
authors.forename: Wei-Lun
authors.initials: WL
authors.lastname: Chen
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University , Guangzhou 510632, People's Republic of China.
authors.forename: Xiao-Qi
authors.initials: XQ
authors.lastname: Zhang
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.|School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Swanson
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.
authors.forename: Joanna E
authors.initials: JE
authors.lastname: Burdette
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States.
authors.forename: Chun-Tao
authors.initials: CT
authors.lastname: Che
mesh_terms: D045784:Abietanes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D018360:Crystallography, X-Ray; D004354:Drug Screening Assays, Antitumor; D019684:Magnoliopsida / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D035281:Plant Tubers / Q000737:chemistry
chemical_list: D045784:Abietanes; C433018:pimarane