First 2-hydroxy-3-methylbut-3-enyl substituted xanthones isolated from plants: structure elucidation, synthesis and antifungal activity.
Two new 2-hydroxy-3-methylbut-3-enyl substituted xanthones, (+/-)-caledol 1 and (+/-)-dicaledol 2 were isolated from a dichloromethane extract of the leaves of Calophyllum caledonicum (Clusiaceae). Compounds 1 and 2 are the first 2-hydroxy-3-methylbut-3-enyl substituted xanthones isolated from natural source. Their structures were elucidated by means of combined analytical methods including HRFABMS, 1D and 2D NMR spectroscopies and also confirmed by total synthesis using biomimetic ortho-prenylphenols photooxygenation (1O2) as a key step. The antifungal activity against Aspergillus fumigatus is reported.
Oger
Jean-Michel
JM
SONAS, UFR des Sciences Pharmaceutiques et Ingénierie de la Santé, 16 Bd Daviers, F-49100 Angers, France. jean-michel.oger@univ-angers.fr
Morel
Cécile
C
Helesbeux
Jean-Jacques
JJ
Litaudon
Marc
M
Séraphin
Denis
D
Dartiguelongue
Caroline
C
Larcher
Gérald
G
Richomme
Pascal
P
Duval
Olivier
O
D001232:Aspergillus fumigatus / Q000187:drug effects; D029759:Calophyllum / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
D044004:Xanthones; C479405:caledol; C479406:dicaledol