title: Structural Revisions of a Class of Natural Products: Scaffolds of Aglycon Analogues of Fusicoccins and Cotylenins Isolated from Fungi.
abstract: The reisolation and structural revision of brassicicene D is described, and inspired us to reassign the core skeletons of brassicicenes C-H, J and K, ranging from dicyclopenta[a,d]cyclooctane to tricyclo[9.2.1.0(3,7)]tetradecane using quantum-chemical predictions and experimental validation strategies. Three novel, highly modified fusicoccanes, brassicicenes L-N, were also isolated from the fungus Alternaria brassicicola, and their structures were unequivocally established by spectroscopic data, ECD calculations, and crystallography. The reassigned structures represent the first class of bridgehead double-bond-containing natural products with a bicyclo[6.2.1]undecane carbon skeleton. Furthermore, their stabilities were first predicted with olefin strain energy calculations. Collectively, these findings extend our view of the application of computational predictions and biosynthetic logic-based structure elucidation to address problems related to the structure and stability of natural products.
authors.affiliation: Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Yongbo
authors.identifier: http://orcid.org/0000-0001-9133-6439
authors.initials: Y
authors.lastname: Xue
authors.affiliation: Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Guang
authors.initials: G
authors.lastname: Du
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Wang
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Junjun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Chinese Academy of Sciences, Kunming, China.
authors.forename: Xiao-Nian
authors.initials: XN
authors.lastname: Li
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Guangmin
authors.initials: G
authors.lastname: Yao
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Zengwei
authors.initials: Z
authors.lastname: Luo
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China. zhangyh@mails.tjmu.edu.cn.
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D001688:Biological Products / Q000737:chemistry*; D003461:Crystallography; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification; D005658:Fungi / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure
chemical_list: D001688:Biological Products; D004224:Diterpenes; D006027:Glycosides; C423222:cotylenin A; C007808:fusicoccin
keywords: NMR spectroscopy; computational chemistry; natural products; structure elucidation; terpenoids