which afforded several fractions, which were pooled based on
their analytical TLC results. The fractions obtained with the mixture of
n-hexane−EtOAc (92:8 v/v) were further chromatographed with a
gradient elution using a mixture of n-hexane−CHCl3 (88:12 and 86:14
v/v) to afford two fractions, labeled as MKF1 and MKF2. Fraction
MKF1 was subjected to preparative TLC (PTLC) using n-hexane−
CHCl3 (85:15 v/v) as the mobile phase in order to purify compound 2
(6 mg, Rf = 0.76, 0.003%).