(II) Aloesin
Aloesin (2-acetonyl-8-D-glucopyranosyl-7-hydroxy-
5-methylchromone) was a glycosylated chromone isolated
from the aloe plant(60) and its structure was rather similar
to flavonols (Figure 4). It modulated melanogenesis via
competitive inhibition of tyrosinase(61). Combined treatment
of aloesin and arbutin seemed to show synergistic
effects by respectively non-competitive and competitive
tyrosinase inhibition(62).