Block

Flavonoids (Table 8). The families of the Hamamelidae (sensu Takhtajan 1969) can be envisaged, from the point of view of the flavonoid evidence, to belong to several groups. One group is void of (or extremely poor in) flavones and dihydroflavones. Thus constituting probably (see above) the most primitive one, it is listed at the top of Table 8. Only two families agree with block 1 in lacking compounds with vic-trihy-droxylated B-rings. The other two already possess such compounds (in form of myricetin), as do practically all families of the Hamamelidae. In the next six families the vic-trihydroxylation is even extended to catechins (GC). Additionally, here flavones and dihydroflavones are common and diversified, reaching biflavones in the Casuarinaceae. Other flavonoids include dihydrochalcones in the Betulaceae and Myricaceae and isoflavonoids in the Fagaceae and Myricaceae.

The relationship of the remaining families is more difficult to perceive. Placement of the Platanaceae into the previous groups, though consistent with the absence of O-methyl derivatives, is inconsistent with the occurrence of C-prenyl flavonoids. Prenylation of flavonoids is an extremely common phenomenon

Table 7. Polyketides and other types of Magnoliidae

Biosynthetic precursors Other

Acetate Acetate Acetate

Pyruvate Pyruvate

Cinnamate Cinnamate Cinnamate

Table 7. Polyketides and other types of Magnoliidae

Biosynthetic precursors Other

Acetate Acetate Acetate

Cinnamate Cinnamate Cinnamate

MYRI

Acp Air

y-Lac

Acp Air Sti

MAGN

ANNO

Ake Aky

y-Lac

a-Pyr Ami

MONI

Pip

LAUR

รป>Ake 0>Aky

y-Lac &Lac

a-Pyr

HIMA

Gal

TRIM

Pip

CANE

Ami

WINT

Ind

CHLO

Ami

PIPE

Ami

a-Pyr Ami

Ami

ARIS

a-Pyr Ami

a-Pyr

LARD

Ant

BERB

Ant

RANU

Pan

PHYT

Sti

Acylphloroglucinols Acp, alkylresorcinols Arl, alkenes Ake, alkynes Aky, indolizidine alkaloids Ind, amides Ami, pyrones Pyr, lactones Lac, galbulimima alkaloids Gal, piptoside Pip, anthraquinones Ant, protoanemonin Pan, stilbenes Sti.

Table 8. Flavonoid types of Hamamelidae

Fiavones

Flavonols

Flavanones

Flava-nonols

Flavans -3-OH

Flavans Anthocy-3,4- anidins di-OH

Other

EUPT

KQog

C

+

TROC

KQ5Q

T

+

MYRO

KQM

C

+

CERC

KQM

AM AR

C

+

RHOI

KQM

PLAT A Los

K Q M G6 G8 og cm o.

a cp P cm op cp

PART

+

Dhccmcp

HAMA A L eg

KQMog

TAR

CGCog

CD

+

BETU CALA6L6

G K Q M og om oa

P N E 5N og

P P6 om

CGCog

C

+

C68 7A68 og om cm

om cm

FAGA A 5A og cm om

K Q M K8 og om oa

NE eg

T ARog

C GC A oa

PCD

+ D og oa

[

JUGL A A6 og

K Q M og om

+

Dhclsfeg

MYRI Com

G K Q M og om

P T2' om cp

PToa

C GC C-G om

+ D-G oa

CASU A.A8.8'A.A.6.0.4'

KQMog

T P

C GC C-G oa

+

Dhccm

MORA A L A2' 5A2' L2' L6'G KQM 5G K2' Q2'

P N N2' 5N2'

PTAR

+

+

Isf cp

7L6' eg om op cp

og om o2m op cp

op cp

AR2' og

CANN A L 7L eg og cp

KQMog

N omcp

+

URTI AL

K Q M og om

+

ULMA ALTogcgomoa

K Q M og eg om

Tog

AR eg om

C

+

CECR

KQ

BARB

kq

Table 9. Phenolic types of Hamamelidae

Gallate derivatives

Diaryl-heptanoids

Neoligans KABO

Stilbenoids

Benzophe-nones and xanthones

CERC G GGG GH GHA Ber om

RHOI G GG

PLAT

HAMA G GG GGOG

GGOG GGesG HH FAGA G GG GGG GOG GGOG GesG GesGesG GesGOG GanGanG GP GGP G GS JUGL G GG +

EUPT TROC MYRO

CERC G GGG GH GHA Ber om

RHOI G GG

PLAT

HAMA G GG GGOG

GGOG GGesG HH FAGA G GG GGG GOG GGOG GesG GesGesG GesGOG GanGanG GP GGP G GS JUGL G GG +

MORA

CANN

URTI

ULMA

CECR

BARB

Addenda to Table 9

1. Gallate-derived units usually bound to polyhydroxylated co-units:

HO 0

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