The FT IR spectra were recorded on a vector 22 instrument. UV
was recorded on Unicam Helos BVI 14 model No. 053925. The 1
H-
and 13C NMR spectra as well as 2D NMR spectra (COSY, HMQC, and
HMBC) were recorded on a Bruker AMX 500 MHz and 100 MHz
NMR (Avance) instruments using the UNIX data solvent. EI MS
spectra were recorded on a Finnigan MAT 312. FAB mass
measurements were performed on Jeol JMS HX 110 mass
spectrometer using glycerol as the matrix. HREI MS was carried
out on Jeol JMS 600 mass spectrometer. Column chromatography
was carried out on silica gel (M and N), 70–230 mesh. Thin layer
chromatography (TLC) was performed on pre-coated silica gel
plates (DC-Alufolien 60 F254 of E. Merck) and spots were located
by using methanolic KOH spraying reagent.