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Chapter – 4 Studies on different types of reactions…..
antimalarial, 255 antiviral, 256 antitumor, 257 herbicidal 258 and also bactericidal
259, 260 activities. They are also identified as antioxidants. 261
Curcumin is a yellow pigment isolated from the rhizome of the
perennial herb Curcuma longa L (turmeric). The chemical structure of
curcumin was elucidated by Lampe et. al. 262
Curcumin has several biological activities. It possesses antiinflammatory,
antioxidant, antibacterial, antihepatotoxic, hypotensive and
hypocholesterolemic properties. 263-266 Tonneses 267 describes curcumin as a
non-toxic compound even at high dosages. It has a dual effect in oxygen
radical reactions, thus it can act as a scavenger of hydroxyl radicals or
catalyse the formation of hydroxyl radicals depending on the experimental
267, 268
conditions.
Curcumin inhibits in vitro lipid peroxide formation by liver homogenates
of oedemic mice. 269 The inflammatory response induced experimentally in
animals appeared to be corelated with disturbances of the regulation of
cellular oxidative process, as is evident from the anti-inflammatory action of
well known antioxidants. There is evidence of a parallel between the inhibition
of aedema formation in mice induced by carrageenan and the decrease in the
production of lipid peroxides in liver homogenate. 269 Modification of groups on
the terminal aromatic rings of curcumin reveals that electron donating groups
increase anti-inflammatory activity. 270 The structural similarity of chalcone like
molecules is expected to exhibit either antagonize or potentiate the biological
activity in question and therefore it was very essential to study further, the
coumarin derivatives possessing such ethylenic linkages-discussed earlier.
4.3.4 CHALCONES OF 3-ACETYL-4-HYDROXYCOUMARIN
4-hydroxycoumarin is known to give 3-substituted-4-hydroxycoumarin
derivatives on electrophilic or nucleophilic attack; acetylation of 4hydroxycoumarin
using glacial acetic acid in presence of phosphorous
oxychloride to yield 3-acetyl-4-hydroxycoumarin is one of it. Subsequent
Department of Chemistry, Saurashtra University, Rajkot – 360 005 205