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Synthesis and Antimicrobial Activity of Some Chalcone Derivatives

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Y. Rajendra Prasad at Andhra University
Y. Rajendra Prasad
Lakshmana Rao Atmakuri
Lakshmana Rao Atmakuri
R. Rambabu
R. Rambabu
R. Rambabu
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In an effort to develop antimicrobial agents, a series of chalcones were prepared by Claisen-Schmidt condensation of appropriate acetophenones with appropriate aromatic aldehydes in the presence of aqueous solution of potassium hydroxide and ethanol at room temperature. The synthesized compounds were characterized by means of their IR, 1H-NMR spectral data and elemental analysis. All the compounds were tested for their antibacterial and antifungal activities by the cup plate method.
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ISSN: 0973-4945; CODEN ECJHAO
E-Journal of Chemistry
http://www.e-journals.net Vol. 5, No.3, pp. 461-466, July 2008
Synthesis and Antimicrobial Activity
of Some Chalcone Derivatives
Y. RAJENDRA PRASAD
*
, A. LAKSHMANA RAO and R. RAMBABU
University College of Pharmaceutical Sciences,
Andhra University,Visakhapatnam-530 003, Andhra Pradesh, India.
dryrp@rediffmail.com; Tel: +91-891-2504224
Received 28 October 2007; Accepted 20 December 2007
Abstract: In an effort to develop antimicrobial agents, a series of chalcones
were prepared by Claisen-Schmidt condensation of appropriate acetophenones
with appropriate aromatic aldehydes in the presence of aqueous solution of
potassium hydroxide and ethanol at room temperature. The synthesized
compounds were characterized by means of their IR,
1
H-NMR spectral data
and elemental analysis. All the compounds were tested for their antibacterial
and antifungal activities by the cup plate method.
Keywords: Chalcone, Synthesis, Antibacterial activity, Antifungal activity
Introduction
Chalcones are well known intermediates for synthesizing various heterocyclic compounds.
The compounds with the backbone of chalcones have been reported to possess various
biological activities such as antimicrobial
1
, anti-inflammatory
2
, analgesic
3
, antiplatelet
4
,
antiulcerative
5
, antimalarial
6
, anticancer
7
, antiviral
8
, antileishmanial
9
, antioxidant
10
,
antitubercular
11
, antihyperglycemic
12
, immunomodulatory
13
, inhibition of chemical
mediators release
14
, inhibition of leukotriene B
4
15
, inhibition of tyrosinase
16
and inhibition of
aldose reductase
17
activities. The presence of a reactive α,β-unsatutated keto function in
chalcones is found to be responsible for their antimicrobial activity. In the present
communication we report the reaction of various acetophenone derivatives with different
aromatic aldehyde derivatives to form chalcones (3
a-l
). The structures of the various
synthesized compounds were assigned on the basis of IR,
1
H-NMR spectral data and
elemental analysis. These compounds were also screened for their antimicrobial activity.
Experimental
Melting points were determined in open capillary tubes and are uncorrected. The IR spectra
were recorded in KBr on Perkin-Elmer BX Spectrophotometer. The
1
H-NMR were recorded
462 Y.RAJENDRA PRASAD et al.
in CDCl
3
on Bruker Spectrospin AV 400 MHz Spectrometer using TMS as an internal
standard. The elemental analyses were performed on Carlo Erba 1108 elemental analyzer.
The purity of the compounds was checked by TLC-using Silicagel-G (Merck). Column
chromatography was performed on Silica gel (Merck, 60-120 mesh).
General procedure for the preparation of 1-(substitutedphenyl)-3-(substituted-
phenyl)-2-propen-1-ones (3
a-l
)
A mixture of substituted acetophenones (0.01 mole) and aryl aldehydes (0.01 mole) was
stirred in ethanol (30 mL) and then an aqueous solution of potassium hydroxide (15 mL)
was added to it. The mixture was kept over night at room temperature and then it was poured
into crushed ice and acidified with dilute hydrochloric acid. The chalcone derivative
precipitates out as solid. Then it was filtered and crystallized from ethanol (Scheme 1).
CH
3
O
R
1
R
2
OHC
R
3
R
4
R
5
R
6
KOH
Room Temp., 24 hrs
R
3
R
4
O
R
1
R
2
R
5
R
6
+
(3a – l)
Scheme I
3
a
: R
1
= R
3
= R
4
= R
6
= H, R
2
= Br, R
5
= Cl
3
b
: R
1
= R
4
= R
6
= H, R
2
= Br, R
3
= R
5
= Cl
3
c
: R
1
= R
3
= R
4
= R
6
= H, R
2
= Br, R
5
= F
3
d
: R
1
= R
3
= H, R
2
= Br, R
4
= R
5
= R
6
= OCH
3
3
e
: R
1
= R
3
= R
4
= R
5
= R
6
= H, R
2
= Br
3
f
: R
1
= OH, R
2
= R
3
= R
4
= R
6
= H, R
5
= Cl
3
g
: R
1
= OH, R
2
= R
4
= R
6
= H, R
3
= R
5
= Cl
3
h
: R
1
= OH, R
2
= R
3
= R
4
= R
6
= H, R
5
= F
3
i
: R
1
= OH, R
2
= R
3
= H, R
4
= R
5
= R
6
= OCH
3
3
j
: R
1
= R
2
= OH, R
3
= R
4
= R
6
= H, R
5
= NO
2
3
k
: R
1
= R
2
= OH, R
3
= R
4
= R
5
= R
6
= H
3
l
: R
1
= OH, R
2
= R
3
= R
4
= R
6
= H, R
5
= Cl
1-(4'-Bromophenyl)-3-(4-chlorophenyl)-2-propen-1-one (3
a
)
Yield 88%; m.p. 191-193
0
C; IR (KBr, cm
-1
): 1732 (C=O), 1637 (CH=CH), 852 (C-Cl), 836
(C-Br);
1
H-NMR (CDCl
3
, δ ppm): 7.81 (1H, d, J=16 Hz, =CH-Ar), 7.34 (1H, d, J=16
Hz, -CO-CH=), 7.30-7.72 (8H, m, Ar-H). Anal. Calcd. for C
15
H
10
OclBr: C, 55.91; H, 3.11;
O, 4.97. Found: C, 55.85; H, 3.22; O, 4.79.
1-(4'-Bromophenyl)-3-(2,4-dichlorophenyl)-2-propen-1-one (3
b
)
Yield 91%; m.p. 148-150
0
C; IR (KBr, cm
-1
): 1736 (C=O), 1632 (CH=CH), 865 (C-Cl), 835
(C-Br);
1
H-NMR (CDCl
3
, δ ppm): 7.80 (1H, d, J=16 Hz, =CH-Ar), 7.40 (1H, d, J=16
Hz, -CO-CH=), 7.35 (1H,s, Ar-H), 8.03 (2H, d, Ar-H), 7.55-7.63 (4H, m, Ar-H). Anal.
Calcd. for C
15
H
9
OCl
2
Br: C, 50.59; H, 2.52; O, 4.49. Found: C, 50.46; H, 2.49; O, 4.56.
1-(4'-Bromophenyl)-3-(4-fluorophenyl)-2-propen-1-one (3
c
)
Yield 86%; m.p. 175-177
0
C; IR (KBr, cm
-1
):1720 (C=O), 1628 (CH=CH), 838 (C-Br), 815
(C-F);
1
H-NMR (CDCl
3
, δ ppm): 7.81 (1H,d, J=16 Hz, =CH-Ar), 7.06 (1H, d, J=16
Hz, -CO-CH=), 7.30-7.74 (8H, m, Ar-H). Anal. Calcd. for C
15
H
10
ObrF: C, 59.03; H, 3.27;
O, 5.24. Found: C, 59.10; H, 3.31; O, 5.15.
1-(4'-Bromophenyl)-3-(3,4,5-trimethoxyphenyl)-2-propen-1-one (3
d
)
Yield 88%; m.p. 138-139
0
C; IR (KBr, cm
-1
): 1728 (C=O), 1636 (CH=CH), 1148 (C-OCH
3
),
842 (C-Br);
1
H-NMR (CDCl
3
, δ ppm): 7.82 (1H, d, J =16 Hz, = CH-Ar), 7. 27 (1H, d, J=16
Hz, -CO-CH=), 3.90 (9H, s, 3 x OCH
3
), 6.79 (2H, s, Ar-H), 7.58 (2H, d, Ar-H), 7.65 (2H, d, Ar-H).
Anal. Calcd. for C
18
H
17
O
4
Br: C, 57.30; H, 4.51; O, 16.98. Found: C, 57.25; H, 4.54; O, 16.85.
Synthesis and Antimicrobial Activity 463
1-(4'-Bromophenyl)-3-phenyl-2-propen-1-one (3
e
)
Yield 91%; m.p. 114-116
0
C; IR (KBr, cm
-1
):1756 (C=O), 1622 (CH=CH), 848 (C-Br);
1
H-NMR
(CDCl
3
, δ ppm): 7.82 (1H, d, J=16 Hz, =CH-Ar), 7.40 (1H, d, -CO-CH=), 7.30-7.78 (9H, m, Ar-H).
Anal. Calcd. for C
15
H
11
OBr: C, 62.73; H, 3.83; O, 5.57. Found: C, 62.75; H, 3.94; O, 5.61.
1-(2'-Hydroxyphenyl)-3-(4-chlorophenyl)-2-propen-1-one (3
f
)
Yield 82%; m.p. 154-156
0
C; IR (KBr, cm
-1
): 3435 (OH), 1647 (C=O), 1582 (CH=CH), 810
(C-Cl);
1
H-NMR (CDCl
3
, δ ppm): 7.94 (1H, d, J=16 Hz, =CH-Ar), 6.70 (1H, d, J=16
Hz, -CO-CH=), 12.80 (1H, s, C-2
'
-OH), 7.25-7.80 (8H, m, Ar-H). Anal. Calcd. for
C
15
H
11
O
2
Cl: C, 69.94; H, 4.25; O, 12.38. Found: C, 69.98; H, 4.29; O, 12.40.
1-(2'-Hydroxyphenyl)-3-(2,4-dichlorophenyl)-2-propen-1-one (3
g
)
Yield 92%; m.p. 178-180
0
C; IR (KBr, cm
-1
): 3434 (OH), 1639 (C=O), 1574 (CH=CH), 862
(C-Cl);
1
H-NMR (CDCl
3
, δ ppm): 7.82 (1H, d, J=16 Hz, =CH-Ar), 6.98 (1H, d, J=16
Hz, -CO-CH=), 12.50 (1H, s, C-2
'
-OH), 7.19 (1H, s, Ar-H), 6.87-.8.80 (6H, m, Ar-H). Anal.
Calcd. for C
15
H
10
O
2
Cl
2
: C, 61.45; H, 3.41; O, 10.92. Found: C, 61.39; H, 3.60; O, 10.80.
1-(2'-Hydroxyphenyl)-3-(4-fluorophenyl)-2-propen-1-one (3
h
)
Yield 87%; m.p. 189-191
0
C; IR (KBr, cm
-1
): 3432 (OH), 1687 (C=O), 1638 (CH=CH), 830
(C-F);
1
H-NMR (CDCl
3
, δ ppm): 7.81 (1H, d, J=16 Hz, =CH-Ar), 6.89 (1H, d, -CO-CH=),
12.70 (1H, s, C-2
'
-OH), 6.90-7.85 (8H, m, Ar-H). Anal. Calcd. for C
15
H
11
O
2
F: C, 74.38; H,
4.54; O, 13.22. Found: C, 74.40; H, 4.52; O, 13.28.
1-(2'-Hydroxyphenyl)-3-(3,4,5-trimethoxyphenyl)-2-propen-1-one (3
i
)
Yield 86%; m.p. 180-182
0
C; IR (KBr, cm
-1
): 3433 (OH), 1636 (C=O), 1570 (CH=CH),
1127 (OCH
3
);
1
H-NMR (CDCl
3
, δ ppm): 7.87 (1H, d, J=16 Hz, =CH-Ar), 7.05 (1H, d, J=16
Hz, -CO-CH=), 12.90 (1H, s, C-2
'
-OH), 3.95 (9H, s, 3 x OCH
3
), 6.91 (2H, s, Ar-H), 6.95-
7.98 (4H, m, Ar-H). Anal. Calcd. for C
15
H
18
O
5
: C, 68.78; H, 5.73; O, 25.47. Found: C,
68.72; H, 5.65: O, 25.39.
1-(2', 4’-Dihydroxyphenyl)-3-(4-nitrophenyl)-2-propen-1-one (3
j
)
Yield 91%; m.p. 138-140
0
C; IR (KBr, cm
-1
): 3414 (C-NO
2
), 1688 (C=O), 1640 (CH=CH),
1324 (C-NO
2
);
1
H-NMR (CDCl
3
, δ ppm): 7.87 (1H, d, J=16 Hz, =CH-Ar), 6.65 (1H, d, J=16
Hz, -CO-CH), 5.32 (1H, s, C-4
'
-OH), 7.18-7.67 (7H, m, Ar-H). Anal. Calcd. for C
15
H
11
O
5
N:
C, 63.15; H, 3.85; O, 28.07; N, 4.91. Found: C, 63.10; H, 3.91; O, 28.35; N, 4.89.
1-(2',4'-Dihydroxyphenyl)-3-phenyl-2-propen-1-one (3
k
)
Yield 65%; m.p. 158-160
0
C; IR (KBr, cm
-1
): 3100 (OH), 1720 (C=O), 1640 (CH=CH); 1H-
NMR (CDCl
3
, δ ppm): 7.93 (1H, d, J=16 Hz, =CH-Ar), 6.81 (1H, d, J=16 Hz, -CO-CH=),
5.40 (1H, s, C-4
'
-OH), 7.10-7.92 (8H,m, Ar-H). Anal. Calcd. for C
15
H
12
O
3
: C, 75.00; H,
5.00: O, 20.00. Found: C, 75.12; H, 5.09; O, 19.98.
1-(2'-Hydroxyphenyl)-3-(4-chlorophenyl)-2-propen-1-one (3
l
)
Yield 91%; m.p. 151-153
0
C; IR (KBr, cm
-1
): 3433 (OH), 1640 (C=O), 1564 (CH=CH), 824
(C-Cl);
1
H-NMR (CDCl
3
, δ ppm): 7.84 (1H, d, J=16 Hz, =CH-Ar), 6.94 (1H, d, J=16
Hz, -CO-CH=), 12.65 (1H, s, C-2
'
-OH), 6.95-7.85 (8H, m, Ar-H). Anal. Calcd. for
C
15
H
11
O
2
Cl: C, 69.94; H, 4.25; O, 12.38. Found: C, 69.59; H, 4.32; O, 12.45.
464 Y.RAJENDRA PRASAD et al
Results and Discussion
Antimicrobial activity
The newly synthesized compounds (3
a-l
) were screened for their antibacterial activity against two
gram positive bacteria viz., Bacillus pumilis, Bacillus subtilis and two gram negative bacteria viz.,
Escherichia coli, Proteus vulgaris by using cup plate method
18,19
. The agar medium was
purchased from HI media Laboratories Ltd., Mumbai, India. Preparation of nutrient broth,
subculture, base layer medium, agar medium and peptone water was done as per the standard
procedure. Discs measuring 6.25 mm in diameter were punched from Whatman No.1 filter paper.
The test compounds were prepared in different concentrations using dimethylsulfoxide. Solutions
of the test compounds were prepared by dissolving 5 mg each in 5 mL of dimethylsulfoxide at a
concentration of 1000 µg/mL. Volumes of 0.05 mL and 0.1 mL of each compound were used for
testing. The cups each of 9 mm diameter were made by scooping out medium with a sterilized
cork borer in a petri dish which was streaked with the organisms.
The solutions of each test compound (0.05 and 0.1 mL) were added separately in the
cups and petri dishes were subsequently incubated. A reference standard for both gram
positive and gram negative bacteria was made by dissolving accurately weighed quantity of
chloramphenicol (200 and 1000 µg/mL, respectively) in sterile distilled water, separately.
The incubation was carried out at 37ºC for 24h. All the experiments were carried out in
triplicate. Simultaneously, controls were maintained by employing 0.1 mL of
dimethylsulfoxide which did not reveal any inhibition. Zones of inhibition produced by each
compound was measured in mm. The results of antibacterial studies are given in Table 1.
Table 1. Antibacterial activity of chalcone derivates
Zone of inhibition (in mm)
B.pumilis B.subtilis E.coli P.vulgaris
Compound
0.05 mL
0.1 mL 0.05 mL
0.1 mL 0.05 mL
0.1 mL 0.05 mL 0.1 mL
3
a
6 8 8 10 7 9 - -
3
b
7 9 9 11 8 10 8 10
3
c
8 10 7 9 9 11 - -
3
d
12 14 11 13 13 15 - -
3
e
8 10 7 9 9 12 8 11
3
f
7 9 8 10 9 11 - -
3
g
8 10 9 11 7 9 - -
3
h
7 9 8 10 7 9 - -
3
i
9 12 8 13 11 14 - -
3
j
10 12 11 13 8 11 9 12
3
k
7 9 8 11 8 10 - -
3
l
7 9 8 10 7 9 - -
Chloramphenicol - - 16 -* 14 -* 10 -*
(-) indicates no zone of inhibition; (-*) indicates inhibition not done.
All those compounds screened for antibacterial activity were also tested for their
antifungal activity using potato-dextrose-agar (PDA) medium by same cup plate method
against Aspergillus niger, Rhizopus oryzae and Aspergillus flavus. The PDA medium was
purchased from HI media Laboratories Ltd., Mumbai, India. Preparation of nutrient broth,
subculture, base layer medium and PDA medium was done as per the standard procedure.
The solutions of test compounds were prepared by a similar procedure described under the
antibacterial activity. Each test compound (5 mg) was dissolved in 5 mL of
dimethylsulphoxide (1000 µg/mL). Volumes of 0.05 and 0.1 mL of each compound were
Synthesis and Antimicrobial Activity 465
used for testing. A reference standard drug fluconazole (200 and 1000 µg/mL respectively)
and dimethylsulphoxide as a control which did not reveal any inhibition. The experiments
were performed in triplicate in order to minimize the errors. Zone of inhibition produced by
each compound was measured in mm. The results of antifungal studies are given in Table 2.
Table 2. Antifungal activity of chalcone derivates
Zone of inhibition (in mm)
A.niger R.oryzae A.flavus Compound
0.05 mL 0.1 mL 0.05 mL 0.1 mL 0.05 mL 0.1 mL
3
a
10 14 9 13 8 11
3
b
6 8 7 10 8 10
3
c
6 8 7 9 6 8
3
d
7 9 8 11 - -
3
e
6 8 7 9 - -
3
f
6 8 7 11 8 9
3
g
7 9 8 9 6 8
3
h
7 8 9 10 7 8
3
i
6 8 7 9 8 9
3
j
6 8 7 9 - -
3
k
6 8 7 9 6 7
3
l
8 9 8 10 6 9
Fluconazole
25 -* - - - -
(-) indicates no zone of inhibition; (-*) indicates inhibition not done.
The screening results revealed that the compounds 3
a-l
showed significant antimicrobial
activity. In particular compounds 3
b
, 3
e
and 3
j
only showed mild inhibitory action on
P.vulgaris. Compounds 3
b
, 3
d
and 3
i
have shown significant activity on B.pumilis, B.subtilis
and E.coli. Compound 3
a
(R = 4-chlorophenyl) have shown high potency especially against
A.niger and R.oryzae. Compounds 3
d
, 3
e
and 3
j
have not shown any inhibition against
A.flavus. All the organisms employed at a concentration of 1000 µg/mL (0.01 mL dose
level) showed considerable antibacterial and antifungal activities and are comparable to that
of standard drugs chloramphenicol and fluconazole, respectively.
Conclusion
Compounds with electron releasing groups such as methoxy and hydroxyl showed better
antibacterial activity than the others not having such groups. Compounds having
pharmacophores such as, chloro, dichloro and fluoro groups have exhibited more antifungal
activity on all the three fungi than the others. These results suggest that the chalcone
derivatives have excellent scope for further development as commercial antimicrobial
agents. Further experiments were needed to elucidate their mechanism of action.
Acknowledgements
The authors are thankful to The Head, Sophisticated Instrumentation Facility, Indian
Institute of Science, Bangalore for providing elemental analysis and to The Vice-President,
Laila Impex, Vijayawada for providing IR and
1
H-NMR spectra.
466 Y.RAJENDRA PRASAD et al
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International Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
... Spin multiplicities were singlet, triplet, multiplet, doublet of doublets, and triplet. Chalcone 1 was produced via a conventional method 13 . ...
... BM-01 was obtained by combining the α-carbon of chalcone 1 with a secondary amine (NH) group (Fig. S1). Chalcone 1 was prepared according to a method mentioned previously 13 . The structural characteristics of BM-01 were ascertained through NMR and IR spectroscopy. ...
... The synthesis and characterization of the pyrazole-derived molecule BM-01 were conducted using spectroscopy ( 1 H, 13 C NMR, ATR-IR). Subsequently, its corrosion inhibition on carbon steel was assessed using a HCl solution (1 M). ...
Design, synthesis, and evaluation of a pyrazole-based corrosion inhibitor: a computational and experimental study
Article
Full-text available
  • Oct 2024
By employing a synergistic blend of experimental and theoretical methodologies, we investigated the corrosion inhibition efficacy of a synthesized pyrazole derivative (BM-01) in a solution of hydrochloric acid (1 M). We utilized molecular dynamics (MD) simulations, scanning electron microscopy (SEM), density functional theory (DFT), complexation, plus electrochemical impedance spectroscopy (EIS). We conducted weight loss (WL) measurements from 298 to 328 K. Inhibition efficacy reached a maximum at a BM-01 concentration of 10⁻³ M, achieving 90.0% (EIS), 90.40% (WL), and 90.38% (potentiodynamic polarization (PDP)). SEM unveiled the shielding of the carbon-steel surface from acid-induced damage by BM-01. The Langmuir adsorption isotherm exhibited a robust fit with a low sum of squares, standard deviation, and a high correlation coefficient. PDP findings indicated that BM-01 acted as a mixed-type inhibitor, predominantly favoring the cathodic process, suggesting potential corrosion-mitigation properties. Theoretical analyses involving DFT, MD simulations, and radial distribution function were conducted to postulate a mechanism and identify an inhibitory layer. Theoretical outcomes aligned closely with experimental data, thereby reinforcing the validity of our findings.
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... 2024, 25, 9718 2 of 21 ment [11]. Halogenated chalcones, while not naturally occurring, can be synthesized through the Claisen-Schmidt condensation [8,9,12]. The promising strategy for the glycosylation of chalcones can be the use of microbial enzymes-among others-as well as whole-cell biotransformation using filamentous fungi as biocatalysts [13,14]. ...
... chlorflavonin, exhibited strong antituberculosis potential with (MIC90 1.56 μM) and was superior to streptomycin treatment [11]. Halogenated chalcones, while not naturally occurring, can be synthesized through the Claisen-Schmidt condensation [8,9,12]. The promising strategy for the glycosylation of chalcones can be the use of microbial enzymes-among others-as well as whole-cell biotransformation using filamentous fungi as biocatalysts [13,14]. ...
... Chalcones and dihydrochalcones may occur in the form of glycosides, making them more stable and soluble in water, which improves their biodistribution and storage in plants [5][6][7]. Introducing a chlorine atom into the chalcone structure may enhance its bioactivity., including antibacterial properties [8][9][10]. When a chlorine atom is introduced onto ring B of 2 ′ -hydroxychalcone, it enhances its antituberculosis activity against strain Mycobacterium tuberculosis H37Rv [9]. ...
Antimicrobial Activity of Chalcones with a Chlorine Atom and Their Glycosides
Article
Full-text available
Chalcones, secondary plant metabolites, exhibit various biological properties. The introduction of a chlorine and a glucosyl substituent to the chalcone could enhance its bioactivity and bioavailability. Such compounds can be obtained through a combination of chemical and biotechnological methods. Therefore, 4-chloro-2′-hydroxychalcone and 5′-chloro-2′-hydroxychalcone were obtained by synthesis and then glycosylated in two filamentous fungi strains cultures, i.e., Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5. The main site of the glycosylation of both compounds by I. fumosorosea KCH J2 was C-2′ and C-3 when the second strain was utilized. The pharmacokinetics of these compounds were predicted using chemoinformatics tools. Furthermore, antimicrobial activity tests were performed. Compounds significantly inhibited the growth of the bacteria strains Escherichia coli 10536, Staphylococcus aureus DSM 799, and yeast Candida albicans DSM 1386. Nevertheless, the bacterial strain Pseudomonas aeruginosa DSM 939 exhibited significant resistance to their effects. The growth of lactic acid bacteria strain Lactococcus acidophilus KBiMZ 01 bacteria was moderately inhibited, but strains Lactococcus rhamnosus GG and Streptococcus thermophilus KBM-1 were completely inhibited. In summary, chalcones substituted with a chlorine demonstrated greater efficacy in inhibiting the microbial strains under examination compared to 2′-hydroxychalcone, while aglycones and their glycosides exhibited similar effectiveness.
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... The interest in the study of chalcones arises from their potent biological activity, including antioxidant, anticancer, anti-inflammatory, antiviral, antibacterial, and antifungal, among many others [13]. Previous research using structure-activity relationship (SAR) studies has shown that the antifungal activity against phytopathogenic fungi of a series of synthetic and natural chalcones is related to the presence of methoxy and hydroxyl groups in their molecular structure [14][15][16]. ...
... In fact, among the 137 chalcones analyzed in the mentioned study, those containing 3,4-methylenedioxy motifs in the A ring were active even when they did not have substituents in the B ring. The synthetized 3,4-methylenedioxychalcone derivatives with better antifungal activity in terms of the inhibition of conidia germination (C, D, and F) share the presence of methoxyl groups on the B ring of the chalcone at the C-3 and C-4 positions, coinciding with other studies that indicate the methoxyl substitutions as a key for the bioactivity of chalcones [14,39,40]. Compound A also showed MIC values of <10 µg/mL. ...
The Effect of 3′,4′-Methylenedioxychalcone Derivatives on Mycelial Growth and Conidial Germination of Monilinia fructicola: An In Silico and In Vitro Study
Article
Full-text available
  • May 2025
Monilinia fructicola causes brown rot on a wide variety of stone fruits, causing several losses in the field and during storage of fruits. Due to the diverse biological activity of chalcones and their derivatives, they have emerged as a promising alternative for controlling phytopathogenic fungi. The aim of this study was to synthesize 3′,4′-methylenedioxychalcone derivatives and evaluate their in vitro inhibitory effect on mycelial growth and the conidial germination of M. fructicola. Additionally, a molecular docking study and the prediction of lipophilicity were carried out to investigate their chemical behavior. The results showed that compound F exhibited the most potent antifungal activity, with EC50 and MIC values of 20.61 µg/mL and <10 µg/mL for mycelial growth and conidial germination, respectively, presenting an adequate lipophilicity (Log p values = 2.79), which would allow proper diffusion through the fungal cell membrane. The in silico study revealed a great number of interactions between compound F and the different active sites of the succinate dehydrogenase enzyme, suggesting a favorable interaction with a binding energy score value of −6.9 kcal/mol, similar to CBE, the native ligand of this enzyme. These types of compounds could provide preventive protection in various stone and other crops.
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... They participate in various chemical reactions and are valuable in the synthesis of a range of heterocyclic compounds [14]. Chalcone serves as a prevalent scaffold in numerous biologically active compounds [15]. Chalcones demonstrated a range of biological and pharmacological activities, including antimicrobial, analgesic, anti-inflammatory, antimalarial, antiviral, and anticancer effects [16][17][18][19][20][21]. ...
Synthesis, Characterization, and Docking Studies of Some New Chalcone Derivatives to Alleviate Skin Damage Due to UV Light
Article
Full-text available
Increasing cases of sunburn is one of the serious problems across the globe. In this connection, there is an urgent requirement for some effective sun screening agents. In the search for the same, nanoemulsions of some new synthesized and characterized chalcone derivatives were prepared and evaluated in vitro and in vivo. In order to meet the said objective, in the first step, vanillin was reacted with 4-aminoacetophenone in the presence of 15% sodium hydroxide and ethanol to synthesize the target compounds (C-1 to C-5). Progress of reaction was monitored using thin-layer chromatography (TLC). The crystals of purified compounds were characterized using spectroscopic techniques such as Infrared (IR) spectroscopy, ¹H-NMR spectroscopy, ¹³C-NMR, and mass spectrometry. We prepared the nanoemulsions of the final compounds (C-1 to C-5) and subsequently evaluated them for in vitro sun protection factor activity. The concentration of the nanoemulsions, consistently ranging from 0.88 to 0.91 mg/mL across all formulations, demonstrated a high degree of consistency. The range of particle size varied from approximately 172 to 183 nm, with low polydispersity index values (approximately 0.11 to 0.15). The negative zeta potentials recorded for all the formulations (ranging from −35.87 mV to −39.30 mV) showed that the nanoemulsions are electrostatically stable enough to keep them from sticking together. The pH values of the nanoemulsions ranged narrowly from approximately 5.00 to 5.16, which indicated the compatibility of emulsion with biological systems and the potential to reduce irritation or instability during administration. The viscosity of the nanoemulsions varied between 2.00 and 2.12 cP. In silico studies were performed using MMP-I and MMP-2 as target receptors. For in vitro SPF evaluation, the Mansur equation was employed. COLIPA guidelines were compiled for in vivo SPF evaluation. The nanoemulsions derived from compounds C-3 and C-4, designated as C-3NE and C-4NE, were more effective as anti-aging agents. Findings suggested the possible scope of further synthesis of newer synthetic derivatives of chalcones for furfur development nanoemulsions for better SPF activity.
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... Chalcones shows activity mainly because of an enone pharmacophore in their structures. 5,6 The chalcone core is made up of two aromatic rings joined by a three-carbon aliphatic chain. 7 These ketones are α,β-unsaturated and comprise of two aromatic rings with distinct substituents. ...
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... Chalcone are made up of open chain flavonoids it contains two aromatic or heteroaromatic moiety are fused by a three carbons having α β unsaturated carbonyl structure (Balaji H. Jawale, et al., 2017;Patange, 2008) [1,28] . The existence of a sensitive α, β unsaturated carbonyl moiety in chalcones is well known to be accountable for its antimicrobial effects (Prasad YR, et al., 2008) [28] . In present times a number of chalcones have been investigated for its cytotoxic, insecticidal, antiviral, enzyme inhibitory, anticancer chemo preventive and mutagenic effects (Won SJ, et al., 2005;Yu DC, et al., 1982) [26,27] . ...
Synthesis and spectroscopic studies of manganese (II) Iron (III) Cobalt (II), Nickel (II) and Copper (II) complexes with oxygen donor chalcone ligand
Article
  • Jun 2024
Selected first transition metals like Manganese (II) Iron (III) Cobalt (II), Nickel (II) and Copper (II) complexation with substituted Dehydroacetic acid Chalcone have been prepared and characterized by spectral and analytical technique's. H 1 NMR scans propose decent contribution of trans hydrogen in CH=CH α β unsaturated moiety this is sign of chalcone formation. Electronic absorption spectral data's of metal coordination compounds moved towards lower or higher wavelength, which confirm the coordination of the Chelato to metal ion which shows the charge transfer band. The prepared Chalcone act as a bidentate ligand for the complexation reaction with Cu(II), Ni(II), Co(II), Mn(II) and Fe(III) ions. Powder X-ray diffractograms studies of the coordination compounds shown that [Fe(C17H16O7)2(H2O)2] and [Mn(C17H16O7)2(H2O)2] are Hexagonal crystal arrangement, whereas Monoclinic crystal arrangement for [Co(C17H16O7)2(H2O)2], [Ni(C17H16O7)2(H2O)2] and [Cu(C17H16O7)2(H2O)2] with P/2 type lattice.
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... The screening of antimicrobial activity of 2-chloro-2′-hydroxychalcone (3), 3-chloro-2′-hydroxychalcone (5), their 2′-O-β-d-(4″-O-methyl)-glucopyranosides (3a and 5a) and 2′-hydroxychalcone (6) revealed that an introduction of a chlorine atom into the flavonoid structure increased their inhibitory effect againt E. coli 10,536, S. aureus DSM 799, P. aeruginosa DSM 939, and C. albicans DSM 1386. A similar effect was observed in the work of Prasad et al., in which chalcones with pharmacophores such as chloro, bromo, and fluoro groups exhibited h antimicrobial and antifungal potential 10 . Likewise, the introduction of a chlorine or bromine atom positively affected the action of pyrazine-based chalcones, which showed anti-staphylococcal and anti-enterococcal activity 60 . ...
Synthesis, fungal biotransformation, and evaluation of the antimicrobial potential of chalcones with a chlorine atom
Article
Full-text available
  • Jul 2024
Chalcones are intermediate products in the biosynthesis of flavonoids, which possess a wide range of biological properties, including antimicrobial and anticancer activities. The introduction of a chlorine atom and the glucosyl moiety into their structure may increase their bioavailability, bioactivity, and pharmacological use. The combined chemical and biotechnological methods can be applied to obtain such compounds. Therefore, 2-chloro-2′-hydroxychalcone and 3-chloro-2′-hydroxychalcone were synthesized and biotransformed in cultures of two strains of filamentous fungi, i.e. Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5 to obtain their novel glycosylated derivatives. Pharmacokinetics, drug-likeness, and biological activity of them were predicted using cheminformatics tools. 2-Chloro-2′-hydroxychalcone, 3-chloro-2′-hydroxychalcone, their main glycosylation products, and 2′-hydrochychalcone were screened for antimicrobial activity against several microbial strains. The growth of Escherichia coli 10,536 was completely inhibited by chalcones with a chlorine atom and 3-chlorodihydrochalcone 2′-O-β-d-(4″-O-methyl)-glucopyranoside. The strain Pseudomonas aeruginosa DSM 939 was the most resistant to the action of the tested compounds. However, chalcone aglycones and glycosides with a chlorine atom almost completely inhibited the growth of bacteria Staphylococcus aureus DSM 799 and yeast Candida albicans DSM 1386. The tested compounds had different effects on lactic acid bacteria depending on the tested species. In general, chlorinated chalcones were more effective in the inhibition of the tested microbial strains than their unchlorinated counterparts and aglycones were a little more effective than their glycosides.
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Apigenin Bioisosteres: Synthesis and Evaluation of their Antioxidant, Antimicrobial, and Anticancer Activities
Research
  • Oct 2024
  • LETT ORG CHEM
A novel series of Apigenin bioisosteres [1(4-chlorophenyl)-3-phenyl prop-2-ene-1-one] non-cyclic derivatives (4a-4c) and [7-hydroxy-2-phenyl-4H-chromen-4-one] cyclic derivatives (9a- 9d) were synthesized. The newly synthesized apigenin bioisosteres were confirmed using UV, IR, NMR, and mass spectroscopic methods. The antioxidant, antibacterial, and anti-cancer activities of all newly synthesized compounds were assessed using the DPPH free radical scavenging capacity, disc diffusion method, and in vitro MTT assay on the human breast cancer MCF-7 cell line. Almost all the synthesized apigenin bioisosteres had greater antioxidant and antimicrobial activity than standard Apigenin. Out of seven compounds (4a-4c and 9a-9d), five compounds were found to exhibit notable antiproliferative activity on the breast cancer cell line (MCF-7), whereas two compounds, 9c and 9d, did not show notable activity. Our analysis suggests that synthesized Apigenin bioisosteres function as prospective antioxidant, antimicrobial, and anticancer agents.
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Green Synthesis and Characterization of 4'-Hydroxy-4-Nitro Chalcone using Grinding Techniques
Article
Full-text available
  • Jul 2024
p>The challenge of developing environmentally friendly synthesis methods for biologically active compounds remains a significant focus in green chemistry. This study aimed to synthesize 4'-hydroxy-4-nitro chalcone from 4-hydroxyacetophenone and 4-nitrobenzaldehyde using a grinding technique and then characterize the synthesized compounds. The 4'-hydroxy-4-nitro chalcone was synthesized via the Claisen-Schmidt grinding method for 45 minutes at room temperature. The grinding results were extracted with chloroform. The formed crystals were tested for purity by thin-layer chromatography (TLC), and further purification was carried out by recrystallization. The synthesized chalcone was characterized using FTIR, 1H-NMR , and 13C-NMR spectroscopy. The chalcone was also tested for antibacterial activity using the disc diffusion method against Staphylococcus aureus and Escherichia coli . The results showed that 4'-hydroxy-4-nitro chalcone could be successfully synthesized from 4-hydroxyacetophenone and 4-nitrobenzaldehyde using the grinding technique, yielding orangish-white crystals with a 70.63% yield and a melting point of 173°C. Purity was confirmed by TLC, and structural characterization was achieved through FTIR, 1H-NMR and 13C-NMR spectroscopy. Antibacterial testing revealed that the synthesized chalcone produced a clear zone diameter of 9.27 mm against S. aureus and 27.88 mm against E. coli . These results indicate that the compound has relatively strong antibacterial activity against E. coli and relatively weak activity against S. aureus . This study demonstrates the effectiveness of the green synthesis method and provides valuable insights into the antibacterial properties of 4'-hydroxy-4-nitro chalcone</p
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Synthesis of Antiparasitic Licorice Chalcones
Article
  • Mar 1995
  • BIOORG MED CHEM LETT
A simple, inexpensive high yield method for preparation of echinatin and licochalcone C is described. Echinatin inhibits the growth of Leishmania parasites in concentrations, in which the proliferation of lymphocytes is only slightly affected, indicating that the compound might be used for treatment of leishmaniasis.
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Structure–activity relationship studies on chalcone derivatives
Article
  • Jan 2003
  • BIOORGAN MED CHEM
Some chalcones exert potent anti-inflammatory activities. 2′,5′-Dialkoxychalcones and 2′,5′-dihydroxy-4-chloro-dihydrochalcone inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)/interferon-γ (IFN-γ)-activated N9 microglial cells and in LPS-activated RAW 264.7 macrophage-like cells have been demonstrated in our previous reports. These compounds also suppressed the inducible NO synthase (iNOS) expression and cyclooxygenase-2 (COX-2) activity in RAW 264.7 cells. In an effort to continually develop potent anti-inflammatory agent, a series of chalcones were prepared by Claisen–Schmidt condensation of appropriate acetophenones with appropriate aromatic aldehyde and then evaluated their inhibitory effects on the activation of mast cells, neutrophils, macrophages, and microglial cells. Most of the 2′,5′-dihydroxychaclone derivatives exhibited potent inhibitory effects on the release of β-glucuronidase and lysozyme from rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP)/cytochalasin B (CB). Some chalcones showed potent inhibitory effects on superoxide anion generation in rat neutrophils in response to fMLP/CB. Compounds 1 and 5 exhibited potent inhibitory effects on NO production in macrophages and microglial cells. Compound 11 showed inhibitory effect on NO production and iNOS protein expression in RAW 264.7 cells. The present results demonstrated that most of the 2′,5′-dihydroxychaclones have anti-inflammatory effects. The potent inhibitory effect of 2′,5′-dihydroxy-dihydrochaclones on NO production in LPS-activated macrophage, probably through the suppression of iNOS protein expression, is proposed to be useful for the relief of septic shock.
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Antimalarial Alkoxylated and Hydroxylated Chalones: Structure−Activity Relationship Analysis
Article
  • Oct 2001
Chalcones with 2‘,3‘,4‘-trimethoxy, 2‘,4‘-dimethoxy, 4‘-methoxy, 4‘-ethoxy, 2‘,4‘-dihydroxy, and 4‘-hydroxy groups on ring B were synthesized and evaluated in vitro against Plasmodium falciparum (K1) in a [3H] hypoxanthine uptake assay. The other ring A was quinoline, pyridine, naphthalene, or phenyl rings with electron-donating or electron-withdrawing substituents of varying lipophilicities. Trimethoxy 6 and 27, dimethoxy 7, 8, 29, and methoxy 31 analogues had good in vitro activities (IC50 < 5 μM). 3-Quinolinyl ring A derivatives were well represented among the active compounds. Hydroxylated chalcones were less active than the corresponding alkoxylated analogues. When evaluated in vivo, 8 and 208 were comparable to chloroquine in extending the lifespan of infected mice. Multivariate data analysis showed that in vitro activity was mainly determined by the properties of ring B. Quantitative structure−activity relationship models with satisfactory predictive ability were obtained for various B ring chalcones using projections to latent structures. A model with good predictability was proposed for 19 active chalcones. Size and hydrophobicity were identified as critical parameters.
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ChemInform Abstract: Synthesis and Activity of a New Series of Chalcones as Aldose Reductase Inhibitors.
Article
  • Nov 1998
  • EUR J MED CHEM
A new series of chalcone derivatives has been synthesized and tested in vitro in order to assess their ability to inhibit aldose reductase enzyme (ALR2) and their specificity towards the target enzyme with respect to other oxidoreductases, such as aldehyde reductase, sorbitol dehydrogenase, and glutathione reductase. All the compounds display affinity for ALR2. The X-ray crystal structure of 1-(2,4-dihydroxyphenyl)-3-(2-methoxyphenyl)propen-1-one was determined.
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Synthesis and Anti‐inflammatory Effect of Chalcones
Article
  • Feb 2000
  • J PHARM PHARMACOL
The process of degranulation of mast cells and neutrophils contributes to inflammatory disorders. Activation of microglial cells and macrophages is believed to be involved in inflammatory, infectious and degenerative diseases of the CNS. Combining the potent inhibition of chemical mediators released by the degranulation of mast cells or neutrophils and from the activated microglial cells or macrophages, would lead to a promising antiinflammatory agent for the treatment of peripheral and central inflammation. A series of chalcone derivatives have been reported to have potent anti-inflammatory activity. In an effort to continually develop potent anti-inflammatory agents, novel series of chalcones, 2′-hydroxy- and 2′,5′-dihydroxychalcones were synthesized and their inhibitory effects on the activation of mast cells, neutrophils, microglial cells and macrophages were evaluated in-vitro. The chalcones were prepared by Claisen-Schmidt condensation of appropriate acetophenones with an appropriate aromatic aldehyde. The alkoxychalcones were prepared with appropriate hydroxychalcones and alkyl iodide and the dihydroxychalcones were prepared by hydrogenation of an appropriate chalcone with Pd/C. Almost all of the hydroxychalcones exhibited potent inhibitory effects on the release of β-glucuronidase and lysozyme from rat neutrophils stimulated with formyl-Met-Leu-Phe/cytochalasin B (fMLP/CB). Of the hydroxychalcones, compound 1 was the most potent inhibitor of the release of β-glucuronidase (IC50=1.6 ± 0.2 μM) and lysozyme (IC50=1.4 ± 0.2 μM) from rat neutrophils stimulated with fMLP/CB. Almost all of the 2′,5′-dialkoxychalcones exhibited potent inhibitory effects on nitric oxide (NO) formation from murine microglial cell lines N9 stimulated with lipopolysaccharide (LPS). Of these, compound 11 showed the greatest effect (IC50=0.7 ± 0.06 μM). The present results demonstrated that most of the chalcone derivatives have an anti-inflammatory effect. The inhibitory effects of dialkoxychalcones, 10–12 on inflammation are probably not due to the inhibition of mast cells and neutrophil degranulation, but are mediated through the suppression of NO formation from N9 cells.
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Synthesis and screening of a combinatorial library of naphthalene substituted chalcones: inhibitors of leukotriene B41NCL Communication No. 6453.1
Article
  • Jul 1999
  • BIOORGAN MED CHEM
A combinatorial mini library of naphthalene substituted chalcones has been prepared by solution phase chemistry. Screening of these mixtures for leukotriene B4 inhibitory activity using human whole blood assay (HWBL) afforded a lead compound, 1-(6-butoxy-2-naphthyl)-3-(4-nitrophenyl)-prop-2-en-1-one (K4A3) with an IC50 value of 18.5 microM.
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Antioxidant and Prooxidant Actions of Prenylated and Nonprenylated Chalcones and Flavanones in Vitro
Article
  • Oct 2000
Prenylated flavonoids found in hops and beer, i.e., prenylchalcones and prenylflavanones, were examined for their ability to inhibit in vitro oxidation of human low-density lipoprotein (LDL). The oxidation of LDL was assessed by the formation of conjugated dienes and thiobarbituric acid-reactive substances (TBARS) and the loss of tryptophan fluorescence. At concentrations of 5 and 25 microM, all of the prenylchalcones tested inhibited the oxidation of LDL (50 microg protein/ml) induced by 2 microM copper sulfate. The prenylflavanones showed less antioxidant activity than the prenylchalcones, both at 5 and 25 microM. At 25 microM, the nonprenylated chalcone, chalconaringenin (CN), and the nonprenylated flavanone, naringenin (NG), exerted prooxidant effects on LDL oxidation, based on TBARS formation. Xanthohumol (XN), the major prenylchalcone in hops and beer, showed high antioxidant activity in inhibiting LDL oxidation, higher than alpha-tocopherol and the isoflavone genistein but lower than the flavonol quercetin. When combined, XN and alpha-tocopherol completely inhibited copper-mediated LDL oxidation. These findings suggest that prenylchalcones and prenylflavanones found in hops and beer protect human LDL from oxidation and that prenylation antagonizes the prooxidant effects of the chalcone, CN, and the flavanone, NG.
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Chalcones from Chinese liquorice inhibit proliferation of T cells and production of cytokines
Article
  • Apr 2002
  • INT IMMUNOPHARMACOL
Licochalcone A (LicA), an oxygenated chalcone, has been shown to inhibit the growth of both parasites and bacteria. In this study, we investigated the effect of LicA and four synthetic analogues on the activity of human peripheral blood mononuclear cell proliferation and cytokine production. Four out of five chalcones tested inhibited the proliferation of lymphocytes measured by thymidine incorporation and by flow cytometry. The production of pro- and anti-inflammatory cytokines from monocytes and T cells was also inhibited by four of five chalcones. Furthermore, intracellular detection of cytokines revealed that the chalcones inhibited the production rather than the release of the cytokines. Taken together, these results indicate that LicA and some analogues may have immunomodulatory effects, and may thus be candidates not only as anti-microbial agents, but also for the treatment of other types of diseases.
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Analgesic and antiinflammatory effects of chalcones isolated from Myracrodruon Urundeuva Allem??o
Article
  • Apr 2003
  • PHYTOMEDICINE
The present work showed analgesic and antiinflammatory activities from a fraction containing three dimeric chalcones (chalcone enriched fraction - CEF), isolated from the stem-bark ethyl acetate extract of Myracrodruon urundeuva Allemao (Anacardiaceae). M. urundeuva is a popular medicinal plant used widely in Northeast Brazil, mainly as a topical female genital tract antiinflammatory. We observed that the CEF (5 and 10 mg/kg body wt., i.p. or p.o.) inhibited acetic acid-induced abdominal contractions in mice. In the formalin test, the CEF (5 and 10 mg/kg body wt.) was more effective intraperitoneally and inhibited predominantly the second phase of response. Naloxone reversed this effect, indicating an involvement of the opioid system. The CEF (10 and 20 mg/kg body wt.) also increased the reaction time to thermal stimuli in the hot-plate test in mice, after i.p. but not after p.o. administration. In the carrageenan-induced paw edema test in mice, the CEF (20 and 40 mg/kg body wt.) decreased paw volume significantly, after i.p. administration 2-4 hours after carrageenan injection. The CEF (40 mg/kg body wt.) was also active orally during the same period of time. The present work is the first report on peripheral and central analgesic effects and antiinflammatory activity of natural dimeric chalcones.
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