All starting materials, reagents were obtained from commercial
suppliers and were used without further purification. Standard
eugenol used in this research was obtained from Merck, Column
chromatography was performed using silica gel 60 (Merck) with the
indicated solvents. Thin-layer chromatography was performed using
0.25 mm silica gel plates (Merck) and monitored by UV lamp at
wavelength 254 nm or visualized with KMnO4
.
1
H and 13C NMR
spectra were recorded on either a Bruker AVANCE III 400 MHz
Spectrometer as solutions in deuteriochloroform (CDCl3
). 1
H NMR
data were reported in the order of chemical shift, multiplicity (s,
singlet; d, doublet; t, triplet; m, multiplet and/or multiple resonances),
number of protons, and coupling constant in hertz (Hz).