title: Four phragmalin orthoesters from the Chinese mangrove Xylocarpus granatum.
abstract: Four new 8,9,30-phragmalin orthoesters (1-4), along with six related known compounds, namely xyloccensins O-S (5-9) and V (10), were isolated and characterized from the twigs and leaves of the Chinese mangrove Xylocarpus granatum. The structures of the new compounds were determined on the basis of extensive spectroscopic analysis and by comparison with those of related known compounds in the literature. The absolute configuration of xyloccensin Q (7) was revised as its enantiomer by X-ray diffraction analysis employing graphite monochromated Cu Kα radiation (λ=1.54178 Å) with a Flack parameter of -0.04 and was further secured by a time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculation. Consequently, the absolute configurations of xyloccensins O (5), P (6), R (8), S (9), and V (10) were all corrected as their corresponding enantiomers, respectively. Xyloccensin S (9) exhibited inhibitory activity against protein tyrosine phosphatase 1B, a potential drug target for the treatment of type II diabetes and obesity, with an IC50 value of 8.72 µg/mL.
authors.affiliation: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Zhen-Fang
authors.initials: ZF
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China.
authors.forename: Ling-Yi
authors.initials: LY
authors.lastname: Kong
authors.affiliation: Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary.
authors.forename: Tibor
authors.initials: T
authors.lastname: Kurtán
authors.affiliation: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Hai-Li
authors.initials: HL
authors.lastname: Liu
authors.affiliation: Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Mándi
authors.affiliation: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.affiliation: Syngenta Jealott's Hill International Research Centre, Berkshire, United Kingdom.
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Gu
authors.affiliation: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Yue-Wei
authors.initials: YW
authors.lastname: Guo
mesh_terms: D018360:Crystallography, X-Ray; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D004952:Esters / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D020128:Inhibitory Concentration 50; D036701:Limonins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D029582:Meliaceae / Q000737:chemistry*; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000037:antagonists & inhibitors
chemical_list: D004952:Esters; D036701:Limonins; C000593079:phragmalin; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1