title: New methylethers of cordatolides from Calophyllum cordato-oblongum and their synthesis.
abstract: Twigs of Calophyllum cordato-oblongum Thw. have been shown to contain cordatolide A-OMe, cordatolide B-OMe, cordatolide C-OMe, cordatolide A, cordatolide B, oblongulide, cordatooblongic acid, friedelin, canophyllol, and sitosterol. Methylation of cordatolide B and the attempted methylation of cordatolide A under acidic conditions gave cordatolide B-OMe and 11,12-anhydrocordatolide. Cordatolide A-OMe, cordatolide C-OMe and 11,12-anhydrocordatolide are new compounds.
authors.affiliation: Natural Products Programme, Institute of Fundamental Studies, Kandy 20000, Sri Lanka. hrwd13@hotmail.com
authors.forename: H R W
authors.initials: HR
authors.lastname: Dharmaratne
authors.forename: G P K
authors.initials: GP
authors.lastname: Marasinghe
mesh_terms: D019380:Anti-HIV Agents / Q000138:chemical synthesis / Q000737:chemistry; D029759:Calophyllum / Q000737:chemistry*; D003374:Coumarins / Q000138:chemical synthesis / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008738:Methyl Ethers / Q000138:chemical synthesis* / Q000737:chemistry*; D008745:Methylation; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry*; D012855:Sitosterols / Q000737:chemistry; D014315:Triterpenes / Q000737:chemistry; D000094042:Lupanes
chemical_list: D019380:Anti-HIV Agents; D003374:Coumarins; D008738:Methyl Ethers; D010936:Plant Extracts; D012855:Sitosterols; D014315:Triterpenes; C025473:gamma-sitosterol; C113860:cordatolide A; C060796:friedelin; D000094042:Lupanes