Isolation of Meliacins from Chisocheton Paniculatus Hiern, their Chemical Transformations to New Limonoids and Screening for Antifungal Activity

Paniculatin (1) (6α-acetoxyazadirone) and Paniculatol (2) (dihydroxycompound of 6α-acetoxyazadirone) are two naturally occurring meliacins have been isolated from the fruits and wood of chisocheton paniculatus Hiern. Chemical transformations of paniculatin and paniculatol gave 2-aminothiazolo [4,5-d] [1,2,20,21,22,23-hexahydro] paniculatin (4a), 2aminothiazolo [4,5-d] [6α,7α-dihydroxy-1,2,20,21,22,23-hexahydro] paniculatin (4b), Dialdehyde (5), 3-hydroxy paniculatol (6), Dialdehyde 7, 2methyloxazolo [4,5-d][1,2,20,21,22,23-hexahydro] paniculatin(9a), 2methyloxazolo [4,5-d][ 6α,7α –dihydroxy-1,2,20,21,22,23-hexahydro] paniculatin(9b). Antifungal activity of the above compounds and their derivatives are reported here. The structures of the new compounds have been elucidated on the basis of elemental analysis and spectral data.