The Geography of Phytochemical Races

4.4 South Pacifi c 201
Table 4.5 Occurrence of fl avonoids in Eucryphia (from Bate-Smith, 1967)
Flavonoidb Chilean speciesa Australian speciesa COR GLU MOO MIL LUC
Caryatin + + − − −
Azaleatin 3-Gal − + − − −
Azaleatin 3-DiGlc + + − − −
Azaleatin 3-GalAra + − − − −
Unidentifi ed fl avanone + + − − −
Quercetin 3-Gal + + − + −
Quercetin 3-Rhm + + − − −
Quercetin 3-DiGly + + − − −
Quercetin 3-TriGly − − + − −
Dihydroquercetin 3-Glyc − − − + −
Kaempferol 3,7-DiMe − − − − +
Unidentifi ed fl avan + + − − −
a COR = E. cordifolia; GLU = E. glutinosa; MOO = E. moorei; MIL = E. milliganii; LUC = E. lucida.
b Gal = galactose; Glc = glucose; Ara = arabinose; Rhm = rhamnose; DiMe = dimethyl (ether).
c Dihydrokaempferol and dihydroquercetin were subsequently reported from E. cordifolia
(Tschesche et al., 1979).
relationship. By contrast, the two Tasmanian and single Australian species studied
exhibited extremely simple fl avonoid profi les showing none of the “specialized”
compounds present in the Chilean species. This conclusion has had to be tempered
somewhat by more recent research involving the Chilean species. Tschesche et al.
(1979) identifi ed the 3-O-rhamnosides of dihydroquercetin and dihydrokaempferol
from E. cordifolia. In a more recent paper, dihydroquercetin 3-O-xyloside
[350], caryatin 7-O-glucoside [351], and jaceidin 5-O-glucoside (jaceidin is 5,7,4′trihydroxy-3,6,3′-trimethoxyfl
avone) [352] were obtained from twigs of E. glutinosa
(Sepulveda-Boza et al., 1993).
The most recent contribution to the chemistry of Eucryphia came from the work
of Wollenweber et al. (2000) who, not surprisingly, examined the fl avonoid components
of glandular exudates of all members of genus, which in the present view
comprises seven species. The tables appear to be completely turned with this subset
of Eucryphia fl avonoids. In contrast to the richness of profi les exhibited by the
Chilean taxa with regard to their polar components, their exudate chemistries are
by far the simplest seen in the genus; E. cordifolia afforded a single compound,
apigenin-7,4′-dimethyl ether [353], and only in trace amounts. The other South
American species, E. glutinosa, yielded only two compounds, apigenin-7,4′-dimethyl
ether and luteolin-7,4′-dimethyl ether [354]. Apigenin-7,4′-dimethyl ether was
also detected in the two Tasmanian species and in the two mainland species,
such as E. jinksii and E. moorei. The richest arrays of aglycones came from the
two Tasmanian species with a profi le based on O-methylated derivatives of apigenin,
luteolin, kaempferol, and quercetin, 17 in E. lucida, and 13 in E. milliganii.
Eucryphia jinksii exhibited a somewhat simpler profi le, based as well on both fl avones
and fl avonols, but clearly distinguished from all other species in the genus
by the capacity to make the 8-oxygenated fl avones isoscutellarein-8,4′-dimethyl