title: Synthesis and hypoglycemic activity of esterified-derivatives of mangiferin.
abstract: OBJECTIVE
  To synthesize three novel esterified-derivatives of mangiferin and evaluate their hypoglycemic activities.
  
  
  METHODS
  Acetic, propionic, and butyric anhydride were reacted with mangiferin, respectively. The hypoglycemic activity of the derivatives was evaluated using a hyperglycemic mouse model induced by streptozotocin (STZ), and the islet cells were checked by biopsy inspection.
  
  
  RESULTS
  7, 2', 3', 4', 6'-penta-acetyl-mangiferin (PAM), 3, 6, 7, 2', 3', 4', 6'-hepta-propionyl-mangiferin (HPM) and 3, 6, 7, 2', 3', 4'-hexa-butyryl-mangiferin (HBM) were synthesized and their structures were identified by MS,(1)H, (13)C NMR, and 2D NMR. These three compounds were reported for the first time. PAM group (0.5, 0.25 mmol·kg(-1)), HPM group (0.5, 0.25 mmol·kg(-1)), and HBM group (0.5, 0.25, 0.125 mmol·kg(-1)) mice showed strong hypoglycemic activity (P < 0.01); mangiferin group (1, 0.5 mmol·kg(-1)), PAM group (0.125 mmol·kg(-1)) and HPM group (0.125 mmol·kg(-1)) showed marginal hypoglycemic activity (P < 0.05); mangiferin group (0.25 mmol·kg(-1)) had the potential for a hypoglycemic effect, although it did not demonstrate that statistically. In histological examination, the islet cells of the PAM, HPM, and HBM groups could recover from the STZ damage; islet cells of the mangiferin group could recover also, but less than the esterified-derivative groups.
  
  
  CONCLUSIONS
  Derivatives could repair the damaged islet cells, and had higher lipid-solubility and stronger hypoglycemic activity than mangiferin itself. There existed a structure activity effect, and a solubility effect relationship: the larger esterification moieties, or the higher lipid-solubility, the stronger the hypoglycemic activity (no ester → acetyl → propionyl → butyryl). Esterified derivatives of mangiferin are potential compounds for new anti-diabetes drugs.
authors.affiliation: School of Pharmaceutical Sciences, Guangxi Medical University, Nanning, China.
authors.forename: Xue-Jian
authors.initials: XJ
authors.lastname: Li
authors.forename: Zheng-Cai
authors.initials: ZC
authors.lastname: Du
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.forename: Bu-Ming
authors.initials: BM
authors.lastname: Liu
authors.forename: Wen-Ji
authors.initials: WJ
authors.lastname: Hu
authors.forename: Wen-Jie
authors.initials: WJ
authors.lastname: Lu
authors.forename: Jia-Gang
authors.initials: JG
authors.lastname: Deng
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy*; D004951:Esterification; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000138:chemical synthesis* / Q000737:chemistry; D007515:Islets of Langerhans / Q000187:drug effects; D008297:Male; D051379:Mice; D015394:Molecular Structure; D044004:Xanthones / Q000008:administration & dosage* / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D007004:Hypoglycemic Agents; D044004:Xanthones; C013592:mangiferin