Total synthesis of munchiwarin, a triprenylated chalcone from Crotalaria medicagenia.
An efficient method is developed for the synthesis of the modified triprenylated chalcone, munchiwarin (1), isolated from the roots of Crotalaria medicagenia. The synthesis of 1 utilizes a Claisen-Schmidt condensation between 2,4-dihydroxy-3,5-C-diprenyl acetophenone and 4-methoxy benzaldehyde in the presence of Ba(OH)2 to yield the unusual chalcone 5 that contains a nine-membered ether ring. Further prenylation of 5 with 1-bromo-3-methylbut-2-ene and its subsequent demethylation with BBr3 gave munchiwarin (1).
Narender
T
T
Division of Medicinal and Process Chemistry, Central Drug Research Institute, Lucknow-226 001 U.P, India. tnarender@rediffmail.com
Reddy
K Papi
KP
Shweta
Srivastava
Kumkum
K
Mishra
D K
DK
Puri
S K
SK
D047188:Chalcones / Q000138:chemical synthesis / Q000737:chemistry*; D029864:Crotalaria / Q000737:chemistry*
D047188:Chalcones; C526353:munchiwarin