kimia organik

1. PHENOLIC COMPOUND =
AROMATIC COMPOUNDS
SUCIATI, S.Si, MPhil, PhD, Apt.
SUCIATI, S.Si, MPhil, PhD, Apt.

2. • Structure
• Biosynthesis
• The presence in plant
• Structure activity relationship
• Isolation
• Identifications
OUTLINE
• Structure
• Biosynthesis
• The presence in plant
• Structure activity relationship
• Isolation
• Identifications

3. • One of major group of plant constituent
• Most plant contain a carbocyclic or
heterocyclic aromatic ring with 1 or more
hydroxyl groups
• Together with chlorophyll, carotenes give
colour to plant
Aromatic compound at a glance
• One of major group of plant constituent
• Most plant contain a carbocyclic or
heterocyclic aromatic ring with 1 or more
hydroxyl groups
• Together with chlorophyll, carotenes give
colour to plant
OH
OH
HO

4. • Ranging from simple compounds to complex
structure
• water soluble (Glycosidic form), found within
plant cell (central vacuola)
• Lipophilic (O-methylation), found in cell
cytoplasma, or cell surface as wax
Aromatic compound at a glace
Phenol
• Ranging from simple compounds to complex
structure
• water soluble (Glycosidic form), found within
plant cell (central vacuola)
• Lipophilic (O-methylation), found in cell
cytoplasma, or cell surface as wax
Arbanol A from Morus alba

5. • Classified based on structural complexity and
biosynthetic origin
A) Simple Phenols ( phenol, phenolic acid and phenolic
ketones)  C6/ C6-C1, C6-C2 nucleus
B) Phenylpropanoid (coumarins, chromones, chromenes,
benzofuran, and lignan) C6 - C3 nucleus
C) Xanthones  C6-C1-C6 skeleton
D) Stilbenoids  C6-C2-C6 nucleus
E) Quinones (benzoquinone, naphthoquinone and
anthraquinone)
F) Flavonoid and Tanin  related to phenolic compound
(Discuss separately)
Classification
• Classified based on structural complexity and
biosynthetic origin
A) Simple Phenols ( phenol, phenolic acid and phenolic
ketones)  C6/ C6-C1, C6-C2 nucleus
B) Phenylpropanoid (coumarins, chromones, chromenes,
benzofuran, and lignan) C6 - C3 nucleus
C) Xanthones  C6-C1-C6 skeleton
D) Stilbenoids  C6-C2-C6 nucleus
E) Quinones (benzoquinone, naphthoquinone and
anthraquinone)
F) Flavonoid and Tanin  related to phenolic compound
(Discuss separately)

6. • Phenol (C6)
Aromatic ring with -OH substitution
• Phenolic Acids (C6-C1)
Aromatic ring with carboxyl group substitution
• Phenolic Ketones (C6-C2)
Aromatic ring with a ketone functionality
A. Simple Phenols
p-hydroquinone
• Phenol (C6)
Aromatic ring with -OH substitution
• Phenolic Acids (C6-C1)
Aromatic ring with carboxyl group substitution
• Phenolic Ketones (C6-C2)
Aromatic ring with a ketone functionality
Gallic acid
Acetophenone

7. • Monomeric form of polyphenol
• Function: component of plant tissue 
associated with lignin and melanin
• Obtain by acid hydrolysis of plant tissue
• Present in alcohol-insoluble fraction of leaves,
or alcohol-soluble fraction as glycosidic or
ester
• Free phenols are rare in nature compare to
phenolic acids
A. Simple Phenols
• Monomeric form of polyphenol
• Function: component of plant tissue 
associated with lignin and melanin
• Obtain by acid hydrolysis of plant tissue
• Present in alcohol-insoluble fraction of leaves,
or alcohol-soluble fraction as glycosidic or
ester
• Free phenols are rare in nature compare to
phenolic acids

8. Example of Phenol
p-Cresol
 Found in:
- leaves of Morus spp.
(Moraceae)
- essential oil of Pimpinella
anisum (Adas manis,
Umbelliferae)
 Used as desinfectant
Catechol
 Found in:
- Grapefruit Citrus paradisi
(Rutaceae)
- Avocado (Persea americana)
(Lauraceae)
 Convulsive agent, topical
antiseptic
 Found in:
- leaves of Morus spp.
(Moraceae)
- essential oil of Pimpinella
anisum (Adas manis,
Umbelliferae)
 Used as desinfectant
 Found in:
- Grapefruit Citrus paradisi
(Rutaceae)
- Avocado (Persea americana)
(Lauraceae)
 Convulsive agent, topical
antiseptic

9. Example of Phenolic Acids
Gallic acid
 Found in:
- Caesalpinia sappan (Secang,
Caesalpiniaceae)
- Psidium guajava (Jambu,
Myrtaceae)
 Antibacterial, antiviral,
antifungal, anti-inflammatory, anti
tumour, astringent
Gentisic acid
 Found in:
- leaves and roots of Citrus spp.
(Rutaceae)
- leaves of Sesamum indicum
(Pedaliaceae)
 Antibacterial and antiviral
agents. Na salt shows analgesic
HO
HO
HO
OH
O
HO
OH
O
OH
 Found in:
- Caesalpinia sappan (Secang,
Caesalpiniaceae)
- Psidium guajava (Jambu,
Myrtaceae)
 Antibacterial, antiviral,
antifungal, anti-inflammatory, anti
tumour, astringent
 Found in:
- leaves and roots of Citrus spp.
(Rutaceae)
- leaves of Sesamum indicum
(Pedaliaceae)
 Antibacterial and antiviral
agents. Na salt shows analgesic

10. Example of Phenolic Acid
Salicylic acid
- usually found as glycoside Salicin
- In human salicin is hydrolysed to salicylic alcohol  oxidation
to form salicylic acid
- Aspirin is the synthetic form of salicylic acid
- Source of salicin: willow bark (Salix spp), poplar bark (Populus
spp) and Viburnum spp
 Analgesic and anti inflammation
Salicylic acid
OH
O
OGluc
Salicin Salicylic alcohol
Salicylic acid
- usually found as glycoside Salicin
- In human salicin is hydrolysed to salicylic alcohol  oxidation
to form salicylic acid
- Aspirin is the synthetic form of salicylic acid
- Source of salicin: willow bark (Salix spp), poplar bark (Populus
spp) and Viburnum spp
 Analgesic and anti inflammation

11. Example of Phenolic Ketones
Acetophenone/Hypnone
 Found in:
- Urtica dioica (Jelatang ayam,
Urticaceae)
 Hypnotic activity, orange odour
in perfume.
Apocynin
 Found in:
- Picrorhiza kurroa
(Scrophulariaceae)
 Antiasthmatic agent
 Found in:
- Urtica dioica (Jelatang ayam,
Urticaceae)
 Hypnotic activity, orange odour
in perfume.
 Found in:
- Picrorhiza kurroa
(Scrophulariaceae)
 Antiasthmatic agent

12. • Skeleton: 3 carbon side chain attached to phenol
• Biosynthetically derived from phenylalanine
• Divided into 2 groups: 1) Hydroxycinnamic acids
and 2) modification of C3 side chain and
hydroxycinnamic acid unit (lignan, coumarin,
chromone, chromene, benzofuran)
B. Phenylpropanoids
Cinnamic acid
OH
• Skeleton: 3 carbon side chain attached to phenol
• Biosynthetically derived from phenylalanine
• Divided into 2 groups: 1) Hydroxycinnamic acids
and 2) modification of C3 side chain and
hydroxycinnamic acid unit (lignan, coumarin,
chromone, chromene, benzofuran)
O
NH2

13. Group 1: Hydroxycinnamic acids
• Skeleton: cinnamic acid with OH substitution at
the aromatic ring
• Most common hydroxycinnamic acids in plant:
caffeic acid, p-coumaric acid, ferulic acid and
sinapic acid
 Found in:
- Green and roasted coffee beans (Coffee arabica)
- Leaves and flowers of Papaver somniferum (Papaveracea)
- Digitalis purpurea (Scrophulariaceae)
 Antibacterial, antifungal, antiviral, anti-oxidant,
analgesic, anti-inflammatory, antihepatotoxic
• Skeleton: cinnamic acid with OH substitution at
the aromatic ring
• Most common hydroxycinnamic acids in plant:
caffeic acid, p-coumaric acid, ferulic acid and
sinapic acid
Caffeic acid
 Found in:
- Green and roasted coffee beans (Coffee arabica)
- Leaves and flowers of Papaver somniferum (Papaveracea)
- Digitalis purpurea (Scrophulariaceae)
 Antibacterial, antifungal, antiviral, anti-oxidant,
analgesic, anti-inflammatory, antihepatotoxic

14. • Modification of the acid moiety in hydroxycinnamic acid
produce alcohols, such as coniferyl alcohol, p-coumaryl
alcohol
Group 2. Modification of C3 side chain
Coniferyl alcohol p- coumaryl alcohol
• Modification of the acid moiety in hydroxycinnamic acid
produce alcohols, such as coniferyl alcohol, p-coumaryl
alcohol
• Other modification of C3 side chain
Chlorogenic acid
• Found in Tea, Coffee and Cacao
• Antibacterial, antitumour,
and antioxidant
Rosmarinic acid
• Found in Rosmarinus officinalis (Rosemary)
• Antioxidant

15. • Related to lignin (constituent of cell wall).
• Dimeric compound which contain 2 units of
phenylpropanoid and linked through the central carbon
of C3 side chain  symmetry
• Maybe undergo further Rx, e.g cyclisation, oxidation.
• Mostly isolated from wood part, only a few from root,
leaf and flower
• Maybe found in glycoside form
• Majority contain OMe group  non polar  isolated
with non polar solvent
• Neolignan: formed by unsymmetrical C-C links in the
side chain
Group 2a. Lignans
• Related to lignin (constituent of cell wall).
• Dimeric compound which contain 2 units of
phenylpropanoid and linked through the central carbon
of C3 side chain  symmetry
• Maybe undergo further Rx, e.g cyclisation, oxidation.
• Mostly isolated from wood part, only a few from root,
leaf and flower
• Maybe found in glycoside form
• Majority contain OMe group  non polar  isolated
with non polar solvent
• Neolignan: formed by unsymmetrical C-C links in the
side chain

16. • Lignin: Constituent of plant cell wall; polymer derived from
sinapyl, p-coumaroyl and coniferyl alcohol

17. Group 2a. Lignan
Phyllanthin
• Isolated from Phyllanthus niruri
(Meniran, Euphorbiaceae)
• Give bitter taste
O
O
H
H
H
H
OCH3
OCH3
H3CO
OCH3
GlcO
OGlc
Acanthoside D
• Isolated from roots Acanthopanax
sessiflorus (Korean Ginseng,
Araliaceae), Eleutherococcus
senticosus (Siberian ginseng,
Araliaceae)
• Stress-reducing activity
Phyllanthin
• Isolated from Phyllanthus niruri
(Meniran, Euphorbiaceae)
• Give bitter taste Acanthoside D
• Isolated from roots Acanthopanax
sessiflorus (Korean Ginseng,
Araliaceae), Eleutherococcus
senticosus (Siberian ginseng,
Araliaceae)
• Stress-reducing activity
O
OCH3
OCH3
O
H
H
O
O
OCH3
Burseran
• Isolated from leaves and stems of
Bursera microphylla (Elephant tree,
Burseraceae)
• Antitumour agent

18. • Contain benzene and furan rings fused together
• Derived from modification of C3 side chain of the
hydroxycinnamic acid moiety
• Structure variation: substitution with OH, OCH3, =O,
addition of another benzene ring, reduction of double
bond in furan ring, etc
• May co-occur with stillbenoids in some plants e.g
Morus spp.
• Distribution: Moraceae, Myrtaceae, Compositae,
Rosaceae and some lichens
Group 2b. Benzofuran
• Contain benzene and furan rings fused together
• Derived from modification of C3 side chain of the
hydroxycinnamic acid moiety
• Structure variation: substitution with OH, OCH3, =O,
addition of another benzene ring, reduction of double
bond in furan ring, etc
• May co-occur with stillbenoids in some plants e.g
Morus spp.
• Distribution: Moraceae, Myrtaceae, Compositae,
Rosaceae and some lichens

19. Group 2b. Benzofuran
Tremetone Dehydrotremetone Toxol
• Tremetone and dehydrotremetone are isolated from
Eupatorium urticaefolium (Compositae)
•Toxol is isolated from Haplopappus heterophyllus (Compositae)
• All 3 compounds are toxic to gold fish, and responsible for milk
sickness in human  causing by
consumption of the plant by cow  pass on to the milk
• Tremetone and dehydrotremetone are isolated from
Eupatorium urticaefolium (Compositae)
•Toxol is isolated from Haplopappus heterophyllus (Compositae)
• All 3 compounds are toxic to gold fish, and responsible for milk
sickness in human  causing by
consumption of the plant by cow  pass on to the milk
Indonesia E. riparium

20. Group 2b. Benzofuran
O
HO
OCH3
OH
CH3
H3C
CH3
Mulberrofuran A
Moracin A
O
OH
HO
OH
Albafuran A
O
OH
OCH3
H3CO
O
O
CH3
H
H
H
Albanol A
• All compounds were isolated from Morus Alba
(Mulberry, Moraceae)
• All compounds showed antifungal activity, except
Albanol A which gave hypotensive activity

21. Group 2b. Benzofuran
O
OH
OCH3
H3CO
O
O
CH3
OH
H
HO
OH
H
H
Albanol A Mulberrofuran C
• Albanol A isolated from Morus Alba (Mulberry,
Moraceae)  hypotensive
• Mulberrofuran C isolated from Morus bombycis
(Moraceae)  hypotensive activity
The same Genus can have similar
metabolites or maybe the same metabolites
 Similar structure can have similar
bioactivity
Morus alba = white mulberry

22. • Isolated from several lichens, e.g
Usnea, Ramalina, Evernia, Parmelia,
Lecanora and Cladonia spp
• Antituberculosis, but not effective
against fungi
• Exist in (-) and (+) forms
Group 2b. Benzofuran
O
OH
H3C
HO
O
CH3
O
CH3
O
OH
H3C
Usnic Acid
(-) form
Usnea
• Isolated from several lichens, e.g
Usnea, Ramalina, Evernia, Parmelia,
Lecanora and Cladonia spp
• Antituberculosis, but not effective
against fungi
• Exist in (-) and (+) forms Ramalina

23. • Aromatic lactones derived from cyclization of Lactones
of hydroxycinnamic acid
• Also occur in glycosidic form
• Grouped into 3 class:
1) Simple coumarins, e.g umbelliferone and esculetin
2) Furanocoumarin, e.g Psoralen
3) Pyranocoumarin, e.g decursinol
Group 2c. Coumarin
• Aromatic lactones derived from cyclization of Lactones
of hydroxycinnamic acid
• Also occur in glycosidic form
• Grouped into 3 class:
1) Simple coumarins, e.g umbelliferone and esculetin
2) Furanocoumarin, e.g Psoralen
3) Pyranocoumarin, e.g decursinol

24. • Aromatic lactones derived from cyclization of Lactones
of hydroxycinnamic acid
• Also occur in glycosidic form
• Grouped into 3 class:
1) Simple coumarins, e.g umbelliferone and esculetin
2) Furanocoumarin, e.g Psoralen
3) Pyranocoumarin, e.g decursinol
Group 2c. Coumarin
• Aromatic lactones derived from cyclization of Lactones
of hydroxycinnamic acid
• Also occur in glycosidic form
• Grouped into 3 class:
1) Simple coumarins, e.g umbelliferone and esculetin
2) Furanocoumarin, e.g Psoralen
3) Pyranocoumarin, e.g decursinol

25. • Simple coumarin normally substituted with OH at C-6 and
C-7  hydroxycoumarin
• Hydroxycoumarin and its glycoside usually found in higher
plants.
• So far 100 families contain coumarin/hydroxycoumarin
• Mostly has antifungal and/or antibacterial activity
• Example of hydroxycoumarin with O-Glc is Cichoriin,
isolated from the flowers of a number of plant including
Artemisia (Compositae); showed antifeedant activity
Group 2c. Coumarin
Coumarin Hydroxycoumarin
(named Esculetin)
Cichoriin
• Simple coumarin normally substituted with OH at C-6 and
C-7  hydroxycoumarin
• Hydroxycoumarin and its glycoside usually found in higher
plants.
• So far 100 families contain coumarin/hydroxycoumarin
• Mostly has antifungal and/or antibacterial activity
• Example of hydroxycoumarin with O-Glc is Cichoriin,
isolated from the flowers of a number of plant including
Artemisia (Compositae); showed antifeedant activity

26. • Furan + Coumarin  Furanocoumarin
• Occurs in fruit and roots of mainly Umbelliferae,
Rutaceae, but also found in Compositae, Leguminosae,
Moraceae, Solanaceae etc
• Antifungal agent in Compositae and Umbelliferae
• More biologically active than simple coumarin
• Showed toxicity to insect, mammals and human such as
aflatoxin
• Other furanocoumarins are allergenic
Group 2c. Coumarin
• Furan + Coumarin  Furanocoumarin
• Occurs in fruit and roots of mainly Umbelliferae,
Rutaceae, but also found in Compositae, Leguminosae,
Moraceae, Solanaceae etc
• Antifungal agent in Compositae and Umbelliferae
• More biologically active than simple coumarin
• Showed toxicity to insect, mammals and human such as
aflatoxin
• Other furanocoumarins are allergenic

27. Isopimpinelin
• Found in several plant including
Pimpinella spp (Umbelliferae) and
Citrus aurantifolius (Jeruk lemon,
Rutaceae)
• Antituberculosis, antifungal, and
toxicity in snail.
Group 2c. Coumarin
Psoralen
• Found in the seed Psoralea spp
(Leguminosae), wood of
Xanthoxyllum flavum (Rutaceae)
• Antituberculosis, also showed
photosensitising activity 
allergenic together with UV light
Linear furanocoumarin:
6,7 disubstitutions
Isopimpinelin
• Found in several plant including
Pimpinella spp (Umbelliferae) and
Citrus aurantifolius (Jeruk lemon,
Rutaceae)
• Antituberculosis, antifungal, and
toxicity in snail.
Psoralen
• Found in the seed Psoralea spp
(Leguminosae), wood of
Xanthoxyllum flavum (Rutaceae)
• Antituberculosis, also showed
photosensitising activity 
allergenic together with UV light

28. Aflatoxin B1
• Found in Aspergillus flavus and A.
parasiticus (Ascomycetes)
• Extremely toxic and carcinogenic to
animal and humans by affecting
DNA, RNA and protein synthesis as
well as lipid metabolism
Group 2c. Coumarin
O O
O
O
O
OCH3
H
H
Pimpinellin
• Found in Pimpinella saxifraga
(Umbelliferae) and Artemisia
canariensis (Compositae)
• Antituberculosis
Angular furanocoumarin:
7,8 disubstitutions
Aflatoxin B1
• Found in Aspergillus flavus and A.
parasiticus (Ascomycetes)
• Extremely toxic and carcinogenic to
animal and humans by affecting
DNA, RNA and protein synthesis as
well as lipid metabolism
Pimpinellin
• Found in Pimpinella saxifraga
(Umbelliferae) and Artemisia
canariensis (Compositae)
• Antituberculosis

29. • Pyran + Coumarin  Pyranocoumarin
• Some pyranocoumarins also loosing the double bond
• Like furanocoumarin occurs in fruit and roots of mainly
Umbelliferae, Rutaceae, but also found in Compositae,
Leguminosae, Moraceae, Solanaceae etc
• Antifungal agent in Compositae and Umbelliferae
Group 2c. Coumarin
• Pyran + Coumarin  Pyranocoumarin
• Some pyranocoumarins also loosing the double bond
• Like furanocoumarin occurs in fruit and roots of mainly
Umbelliferae, Rutaceae, but also found in Compositae,
Leguminosae, Moraceae, Solanaceae etc
• Antifungal agent in Compositae and Umbelliferae

30. Group 2c. Coumarin
Seselin
 Found in:
-Seseli indicum (Umbelliferae)
- Foeniculum vulgare (Adas,
Umbelliferae)
- Roots of Citrus aurantium
(Rutaceae)
 Antifungal activity
Xanthyletin
Found in:
- Bark of Xanthoxyllum americanum
(Rutaceae)
- Wood of Citrus aurentifolia
(Rutaceae)
Antitumour and antibacterial
Seselin
 Found in:
-Seseli indicum (Umbelliferae)
- Foeniculum vulgare (Adas,
Umbelliferae)
- Roots of Citrus aurantium
(Rutaceae)
 Antifungal activity
Xanthyletin
Found in:
- Bark of Xanthoxyllum americanum
(Rutaceae)
- Wood of Citrus aurentifolia
(Rutaceae)
Antitumour and antibacterial
F. vulgare

31. • Chromone: benzopyrone, aromatic ring fused with pyrone ring.
• Related to flavonoid
• Chromene: benzopyran, aromatic ring fused with pyran ring
Group 2d. Chromone and Chromene
Coumarin
Chromene
Chromone
• Chromone: benzopyrone, aromatic ring fused with pyrone ring.
• Related to flavonoid
• Chromene: benzopyran, aromatic ring fused with pyran ring

32. Group 2d. Chromone and Chromene
Khellin
• Furanochromone
• found in the seed of Ammi
visnaga (Umbelliferae)
• vasodilator for angina pectoris
O
CH3
CH3
H3CO
R
Procene 1, R = H
Procene 2, R = OCH3
• Chromene
• Found in Ageratina aromatica
(Compositae)
•Insecticidal activity, antijuvenile
hormone in insect
Khellin
• Furanochromone
• found in the seed of Ammi
visnaga (Umbelliferae)
• vasodilator for angina pectoris
• Chromene
• Found in Ageratina aromatica
(Compositae)
•Insecticidal activity, antijuvenile
hormone in insect

33. • C6-C1-C6 skeleton
• Biosynthetically related to flavonoid
• Found in the free state, either as trihydroxy (3x OH),
tetrahydroxy (4xOH), or maybe methylated (CH3)
• Maybe glycosilated
• Hydroxyxanthones mainly found in Gentianaceae and
Guttiferae (roots and leaves)
• Bioactivity reported: antitumour, antimicrobial,
antiinflammatory
C. Xanthones
• C6-C1-C6 skeleton
• Biosynthetically related to flavonoid
• Found in the free state, either as trihydroxy (3x OH),
tetrahydroxy (4xOH), or maybe methylated (CH3)
• Maybe glycosilated
• Hydroxyxanthones mainly found in Gentianaceae and
Guttiferae (roots and leaves)
• Bioactivity reported: antitumour, antimicrobial,
antiinflammatory

34. C. Xanthones
O
O OH
OH
OH
H3CO
Bellidifolin
• Found in Gentiana lactea and
Swertia chirata (Gentianaceae)
• Tuberculostatic agent,
antihepatotoxic and strong
mutagenic activity againts
Salmonella typhimurium
O
O OH
OH
OH
HO
Demethylbellidifolin
• Found in:
-aerial part of Gentiana lactea
as glycoside
-Gentiana campestris
(Gentianaceae)
• weak mutagenic activity
againts Salmonella
typhimurium
Bellidifolin
• Found in Gentiana lactea and
Swertia chirata (Gentianaceae)
• Tuberculostatic agent,
antihepatotoxic and strong
mutagenic activity againts
Salmonella typhimurium
Demethylbellidifolin
• Found in:
-aerial part of Gentiana lactea
as glycoside
-Gentiana campestris
(Gentianaceae)
• weak mutagenic activity
againts Salmonella
typhimurium

35. C. Xanthones
Other structure modifications
Mangiferin
(C-glycoside)
- Isolated from Mango leaves
(Mangifera indica)
- As Antioxidant, antiviral,
anticancer, analgesic,
hepatoprotective, antidiabetic.
α-Mangosteen
- Isolated from pericarp of
Garcinia mangostana
(Manggis)
- As Antioxidant,
antidiabetic.
Mangiferin
(C-glycoside)
- Isolated from Mango leaves
(Mangifera indica)
- As Antioxidant, antiviral,
anticancer, analgesic,
hepatoprotective, antidiabetic.
Norswertianolin
(O-glycoside)

36. • Aromatic compound with C6-C2-C6 skeleton (two
benzene ring connected with an alkene)
• Exist in several structure modifications
• Divided into 2 major groups:
1) Stilbenes and bibenzyl
2) Phenanthrenes and dihydro phenanthrene
D. Stilbenoids
• Aromatic compound with C6-C2-C6 skeleton (two
benzene ring connected with an alkene)
• Exist in several structure modifications
• Divided into 2 major groups:
1) Stilbenes and bibenzyl
2) Phenanthrenes and dihydro phenanthrene

37. • Occur in free state or glycosidic form
• Commonly found in:
- Orchid bulb (normal and when infected by fungi as
phytoalexin)
- Hearthwood of Pinus spp, Eucalyptus  resistance to
fungal attack due to the presence of this aromatic
compound
D. Stilbenoids
• Occur in free state or glycosidic form
• Commonly found in:
- Orchid bulb (normal and when infected by fungi as
phytoalexin)
- Hearthwood of Pinus spp, Eucalyptus  resistance to
fungal attack due to the presence of this aromatic
compound

38. Stilbene and Bibenzyl
D. Stilbenoids
Stilbene Bibenzyl
Dihydroresveratrol
Found in:
 Morus spp (Moraceae)
Dioscorea bulbifera (Dioscoreaceae)
as phytoalexin
Antifungal, antibacterial
Oxyresveratrol
Found in:
 Morus alba, Artocarpus lakoocha
(Moraceae)
Antifungal

39. Phenanthrene and Dihydrophenanthrene
D. Stilbenoids
Phenanthrene Dihydrophenanthrene
Dihydroresveratrol
Found in:
 Loroglossum hircinum
(Orchidaceae)
as phytoalexin
Antifungal
Isobatatasin I
Found in:
 Dioscorea rotunda
(Dioscoreaceae)
Antifungal

40. D. Stilbenoids
Which one
Stilbene?
Bibenzyl?
Phenanthrene?
Dihydrophenanthrene?
Question
Which one
Stilbene?
Bibenzyl?
Phenanthrene?
Dihydrophenanthrene?

41. QUINONE
• Polycyclic aromatic compounds in which one hexane
ring contains two p-substitution carbonyl group
• Usually attached to another benzene ring with
or without OH substitution
• Polycyclic aromatic compounds in which one hexane
ring contains two p-substitution carbonyl group
• Usually attached to another benzene ring with
or without OH substitution
O
O

42. QUINONE
• Quinone give colour ranging from yellow to almost black
In plant give little contribution to plant colour  because
quinone present in bark, hearthwood, root or elsewhere in
which their present are hidden by other pigments
In Fungi  quinone provide colour
e.g. Culture of Penicillium is pigmented by anthraquinone
• Quinones also found in: Marine organisms, such as Sponge,
Sea Urchin
• Ranging from lipophilic (Non polar)  Polar
Non Polar: alkylated or substitution with isoprenyl group
Polar: Glycosilation (Glc) or hydroxylation (OH)
• Quinone give colour ranging from yellow to almost black
In plant give little contribution to plant colour  because
quinone present in bark, hearthwood, root or elsewhere in
which their present are hidden by other pigments
In Fungi  quinone provide colour
e.g. Culture of Penicillium is pigmented by anthraquinone
• Quinones also found in: Marine organisms, such as Sponge,
Sea Urchin
• Ranging from lipophilic (Non polar)  Polar
Non Polar: alkylated or substitution with isoprenyl group
Polar: Glycosilation (Glc) or hydroxylation (OH)

43. QUINONE
Example of alkylated/isoprenylated quinone
Geranylbenzoquinone
Emodin 8-Glucoside
O
O
OGlc OH
CH3

44. • Based on structure and molecular weight
1) Benzoquinones
2) Naphthoquinones
3) Anthraquinones
Classification of Quinones
• Based on structure and molecular weight
1) Benzoquinones
2) Naphthoquinones
3) Anthraquinones

45. Benzoquinones
Skeleton
• Some benzoquinone involve in photosynthesis and cellular
respiration
Group 1. Plastoquinone, e.g plastoquinone-9
Group 2. Ubiquinone, e.g Ubiquinone-10
• These group of benzoquinones are distributed in trace
amount in all green plants
• Some benzoquinone involve in photosynthesis and cellular
respiration
Group 1. Plastoquinone, e.g plastoquinone-9
Group 2. Ubiquinone, e.g Ubiquinone-10
• These group of benzoquinones are distributed in trace
amount in all green plants
O
O
CH3
CH3
H3CO
H3CO
10
Ubiquinone-10 Plastoquinone-9

46. Naphthoquinone
Skeleton
• Structure ranging from simplest one with one hydroxy
substitution to the skeleton  complex such as isoprenyl
substitution and dimeric form
• Characteristic: dark pigment
example: henna plant (Lawsonia inermis)  produced
pigment (lawsone)  hair dye or skin art, also used on the
nails of Egyptian mummies
O
O
• Structure ranging from simplest one with one hydroxy
substitution to the skeleton  complex such as isoprenyl
substitution and dimeric form
• Characteristic: dark pigment
example: henna plant (Lawsonia inermis)  produced
pigment (lawsone)  hair dye or skin art, also used on the
nails of Egyptian mummies
Lawsone = henna
To release this compound
from the leaves 
smashed together with
mild acidic solution

47. Naphthoquinone
Lapachol
Isopentenyl side chain
• Isolated from Haplophragma adenophyllum
(Bignoniaceae), Hibiscus tiliaceus (Malvaceae)
and several other plants.
•Antitumour activity, cytotoxic (high dose),
immunostimulator (low dose)
• The isopentenyl side chain play important role
in antitumour activity. Modification to the side
chain  loss or reduce activity
• Isolated from Haplophragma adenophyllum
(Bignoniaceae), Hibiscus tiliaceus (Malvaceae)
and several other plants.
•Antitumour activity, cytotoxic (high dose),
immunostimulator (low dose)
• The isopentenyl side chain play important role
in antitumour activity. Modification to the side
chain  loss or reduce activity

48. Naphthoquinone
Example of dimeric
naphthoquinone
(Binaphthoquinone)
O
H3C
CH3
Example of ortho
naphthoquinone
Isodiospyrin
• Isolated from stem bark of Diospyros
usambarensis
• Antifungal and cytotoxic
O
OH
O
O
HO
Hibiscoquinone A
• Isolated from heartwood of
Blue mahoe Hibiscus elatus
and H. tiliaceus (Malvaceae)
• Natural dye in plant, bluish
grey and red of hearthwood

49. Anthraquinones
Skeleton
• Largest group of plant quinone
• Structure modification: Substitution with OH group, Dimer
• Usually occurs as O-glycoside or C-glycoside
• Red or purple colour pigment rather than yellow
• Known as dye for textile e.g. from Rubia tinctora
• Main anthraquinone containing plants: Cassia spp.
(Leguminoceae), Rubia spp (Rubiaceae), Aloe spp
(Liliaceae).
• Most of Anthraquinone shows laxative effect
O
O
• Largest group of plant quinone
• Structure modification: Substitution with OH group, Dimer
• Usually occurs as O-glycoside or C-glycoside
• Red or purple colour pigment rather than yellow
• Known as dye for textile e.g. from Rubia tinctora
• Main anthraquinone containing plants: Cassia spp.
(Leguminoceae), Rubia spp (Rubiaceae), Aloe spp
(Liliaceae).
• Most of Anthraquinone shows laxative effect

50. Anthraquinones
Sennoside A
• Isolated from leaves of Cassia senna , fruit C. angustifolia
(Leguminosae) and rhizome Rheum palmatum (Polygonaceae)
•Dimeric form of antharaquinone
• Used for treatment of chronic constipation  strong laxative
• the aglycone form unabsorbed in the body
• the anthrone form  cause laxative effect by increasing
peristaltic action and inhibition of water and electrolyte
resorption in intestinal mucosa
Sennoside A
• Isolated from leaves of Cassia senna , fruit C. angustifolia
(Leguminosae) and rhizome Rheum palmatum (Polygonaceae)
•Dimeric form of antharaquinone
• Used for treatment of chronic constipation  strong laxative
• the aglycone form unabsorbed in the body
• the anthrone form  cause laxative effect by increasing
peristaltic action and inhibition of water and electrolyte
resorption in intestinal mucosa

51. Anthraquinones
Aloe-Emodin
• Found in leaves Cassia senna
and some Aloe spp.
• Chatartic and antileukaemic
activity, anti bacteria
• Help to protect teak wood from
termite
• Also found as C-glycoside
compound (Barbaloin) in Aloe
spp (e.g A.vera)
• Commercially used as purgative
Barbaloin O
O
O
O
OH
OH
SMe
OH
OH
HO
Urdamycinone B
- Isolated from Streptomyces sp
(sponge Xestospongia sp)
-Inhibit Plasmodium falciparum K1
strain and Mycobacterium
tuberculosis
Aloe-Emodin
• Found in leaves Cassia senna
and some Aloe spp.
• Chatartic and antileukaemic
activity, anti bacteria
• Help to protect teak wood from
termite
• Also found as C-glycoside
compound (Barbaloin) in Aloe
spp (e.g A.vera)
• Commercially used as purgative
Urdamycinone B
- Isolated from Streptomyces sp
(sponge Xestospongia sp)
-Inhibit Plasmodium falciparum K1
strain and Mycobacterium
tuberculosis

52. Detection of Phenolic Compounds
Colour reaction:
FeCl3 1% in H2O or EtOH  give green, red,
purple, blue or black (This method, rarely used
now)
Thin layer Chromatography (TLC)
- UV active (short wavelength e.g 254 nm)
- spray with Vanilin-HCl or Vanilin-H2SO4 give
certain colour, e.g simple phenols give red colour
- quinon is pigment  can be detected from the
colour
- spray with DNP reagent give orange colour
(Carbonyl group)
Colour reaction:
FeCl3 1% in H2O or EtOH  give green, red,
purple, blue or black (This method, rarely used
now)
Thin layer Chromatography (TLC)
- UV active (short wavelength e.g 254 nm)
- spray with Vanilin-HCl or Vanilin-H2SO4 give
certain colour, e.g simple phenols give red colour
- quinon is pigment  can be detected from the
colour
- spray with DNP reagent give orange colour
(Carbonyl group)

53. Detection of Phenolic Compounds
UV spectra
Spesific bathochromic shifts in alkali e.g Coumaric
acid in EtOH gave λmaks 227 and 310 nm  in
EtOH + NaOH  λmaks 335 nm
Nuclear Magnetic Resonance
1H NMR signals around 7 ppm  from the
aromatic moiety
13C NMR signal around 170-200 ppm  from the
carbonyl group
UV spectra
Spesific bathochromic shifts in alkali e.g Coumaric
acid in EtOH gave λmaks 227 and 310 nm  in
EtOH + NaOH  λmaks 335 nm
Nuclear Magnetic Resonance
1H NMR signals around 7 ppm  from the
aromatic moiety
13C NMR signal around 170-200 ppm  from the
carbonyl group

54. Separation of Phenolic Compounds
Depend on the polarity of compounds
Polar: phenolic compound with glycoside or with
OH substitution
Non Polar: Free Phenols

55. Separation of plant phenolics
by GC is possible but limited
for volatile and termal stable
compounds
For non volatile compounds
 Methyl, acetate or more
common Trimethylsilyl
derivatives should be made
Separation of plant phenolics
by GC is possible but limited
for volatile and termal stable
compounds
For non volatile compounds
 Methyl, acetate or more
common Trimethylsilyl
derivatives should be made

56. Separation of coumarins by Liquid Chromatography

57. Example of 1H NMR Spectrum of simple phenol
Solvent
CDCl3
Syringaldehyde
2
1
1
1
2
Solvent
CDCl3

58. Example of UV Spectrum of xanthone
258
283
318
337
Du et al, J. Nat. Prod., 2010, 73 (8), pp 1422–1426
Puniceaside A

59. Example of IR Spectrum of xanthone
Du et al, J. Nat. Prod., 2010, 73 (8), pp 1422–1426
C=O stretching
OH stretching

60. Example of 1H NMR Spectrum of xanthone
Aromatic region
Du et al, J. Nat. Prod., 2010, 73 (8), pp 1422–1426
Aromatic region
Glucose region

61. Example of 13C NMR Spectrum of xanthone
Du et al, J. Nat. Prod., 2010, 73 (8), pp 1422–1426

62. Further reading
1) Hostettmann, K. et al. Handbook of Chemical and
Biological Plant Analytical Methods, Volume I and II,
2014, Chichester: John Wiley&Sons.
2) Hostettmann, K and Marston, A. Preparative
Chromatography Techniques-Application in natural
product isolation, 1998, 2nd Edition, Lausanne:
Springer.
3) Harborne, J.B; Baxter, H; Moss, G.P, Phytochemical
Dictionary: A Handbook of bioactive compounds from
plants, 1999, London: Taylor&Francis.
4) Pengelly, A, The Constituent of Medicinal Plants, 2nd
edition, 2004, Cambridge: CABI publishing
1) Hostettmann, K. et al. Handbook of Chemical and
Biological Plant Analytical Methods, Volume I and II,
2014, Chichester: John Wiley&Sons.
2) Hostettmann, K and Marston, A. Preparative
Chromatography Techniques-Application in natural
product isolation, 1998, 2nd Edition, Lausanne:
Springer.
3) Harborne, J.B; Baxter, H; Moss, G.P, Phytochemical
Dictionary: A Handbook of bioactive compounds from
plants, 1999, London: Taylor&Francis.
4) Pengelly, A, The Constituent of Medicinal Plants, 2nd
edition, 2004, Cambridge: CABI publishing