5. The name coumarin is derived
from the carribbean word
―coumarou‖ for the tonka tree
from which coumarin with the
characteristics aroma of new-
mown hay was isolated.
6. Unsubstituted coumarin is
widespread in nature in free form or
as glycoside.
coumarins along with its derivative
occurs abundantly in plant families
such as
umbelliferae,rutaceae,leguminaceae
,
orchidaceae,asteraceae,guttiferae,
thymelaceae and solanaceae.
7. Coumarins play role in plant
protection and are biosynthesized
―de novo‖ in stress conditions as
phytoalexins.
In low concentration they show
synergistic activity with plant growth
promoting.
8. Biological activity of coumarin is
diverse and depend on their
chemical structure.
Oldest medicine from this group
is dicoumarol ,isolated from
Melilotus alba linn. have
antithrombotic and
anticoagulative properties.
10. Coumarins occur in plants in free
form or as glycosides.
Aglycone are soluble in
petrol,benzene,ether,chloroform,
diethylether,alcohol(nonpolar
solvent)
Glycosides are soluble in water and
alcohols(polar solvent)
12. 1--simple coumarins with
substituents both in benzene ring
and pyrone ring
2--furanocoumarins with
substituents on benzene nucleus or
pyrone ring
3--pyranocoumarins with
substituents on benzene and pyrone
rings
20. COUMARIN GLYCOSIDE
Acsulin- bark of Aesculus
hippocastanum
family-Hippocastanaceae
Cichorin-flowers of Cichorium intybus
linn
family-Compositae
Daphnin-bark of Daphne mezerium
family-Thymelaceae
Fraxin-bark of Fraxinus excelsir linn.
family-Oleaceae
21. FURANOCOUMARIN
GLYCOSIDE
Khellol-seeds of Eranthis hyemalis linn
family-Ranunculaceae
Visnagin-seeds of Ammi visnaga
family-Umbelliferae
Psoralea-dried ripe fruit of Psoralea
corylifolia linn
family-Leguminaceae
23. Continous hot percolation n
Dried sample, ground in to small
particles and placed in a porous
cellulose thimble
Thimble placed in extracted
chamber followed by flask
heated with solvent and a
condenser
25. SUPERCRITICAL FLUID
EXTRACTION
Principle- supercritical fluid is applied as
an extractant
Advantages- high process speed
lack of organic solvent
possibility of coupling with
Other methods like GC,HPLC
Used for separation of furanocoumarins
from Angelica archangelica.
26. isolation
Based on lactone type of coumarin
structure
PROCEDURE—alcoholic solution of
pottassium hydroxide crashes the
lactone ring in coumarin result in
coumaric acid
After acidification these acid cyclize to
coumarin again
27. NEW METHODS OF
ISOLATION
Sublimation and fractionating
distillation in high vaccum
Crystallization from organic solvents
Distillation with water vapours
28. GENERAL CHEMICAL TEST
DRUG 3 volume propylene glycol
5 volume acetic acid
43 volume water and shake
blue fluorescence under UV light
DRUG
NaOH solution
yellow fluorescence
under UV light
29. THIN LAYER
CHROMATOGRAPHY
TLC IS used for identification of
compounds presented in plant
extract by retention parameters as
well as UV spectra taken directly
from the layer by densitometry.
33. 2-D TLC
Adsorbent-diol silica(polar bonded)
1st direction eluent-10% methanol in
water
2nd direction eluent-100% diisopropyl
ether
PRINCIPLE-coumarins are identified by
comparing retardation factors in both
directions.
34. PREPARATIVE TLC
PRINCIPLE-Components are applied in
the form of a band and
rechromatography of partly separated
fractions.
For separation of coumarins from
Heracleum sosnowskyj fruits extract is
applied as band on silanized silica
layer eluted with methanol:water(6:4).
35. UV-SPECTROSCOPY
ὰ-pyrone-300 nm
Unsubstituted coumarins-274nm and
311nm
7-hydroxycoumarins-217nm and 315-
330nm
Linear furanocoumarins-205-225nm and
240-255nm
Angular furanocoumarins-240-255nm and
260-270nm are abssent
36. SPECTRAL DATA OF
HYDROXYCOUMARINS
COUMARIN EtOH ʎmax WATER HOAc UV light BAW
AGLYCONE
coumarin 212,274,282,312 67 76 None 92
umbelliferone 210,240,325 57 60 Bright blue 89
aesculetin 230,260,303,351 28 45 Blue 79
scopoletin 229,253,300,346 29 51 Blue violet 83
daphnetin 215,263,328 61 54 Pale yellow 81
GLYCOSIDE Water BN BAW
aesculin 224,252,293,338 56 13 Clear blue 53
scopolin 227,250,288,339 64 44 mauve 53
39. ₁H-NMR SPECTROSCOPY
NMR spectra of coumarins H-3 and H-4
protons exhibits characterstics chemical shift
which distinguish different coumarin
Upfield shift of 0.17 ppm of H-3 Proton in 7-
oxygenated coumarins as compared with
coumarins is due to electron release resulting
in electron density at C-3
An oxygen at C-5 shift the resonance of H-4
downfield by 0-3 ppm due to peri effect
41. MASS SPECTROMETRY
Coumarin on electron impact gives a
strong molecular ion peak (M⁺) at m/e
146 (76%) and a base peak at m/z
118(100%) by the loss of 28 mass units
equivalent to carbon monoxide
7-hydroxy coumarin show a strong M⁺ion
at m/e 162(80%) and base peak at m/z
134 due to loss of carbon monoxide
45. REFERENCES
Harborne J.B,Phenylpropanoid,A guide
to modern techniques of plant analysis
2nd,champan and hall,New york 44-47
Kar Ashutosh ,coumarin
glycoside,pharmacognosy and
pharmacobiotechnology,new age Ltd.
New delhi 512-515
Kowalska teresa,application of tlc in
analysis of coumarin,TLC in
phytochemistry,CRC press, London 78-
84
Bhatt S.V chemistry of natural products
norosa pulisher 412-416