Journal of Chemistry
3
124.98, 122.87, 116.84, 114.98; Anal. Calc.; % C, 50.28; H, 2.48
Found: % C, 50.24; H, 2.50.
Panasonic, Japan) was used to keep all cells at 37∘C during the
experiments. Before the treatment of chalcone compounds,
the viability ratios of the cells were identified by 0.4% trypan
blue. If the viability ratios were under 90%, we did not initiate
the experiments [36].
(2E)-1-(5-Bromo-1-benzofuran-2-yl)-3-(3-nitrophenyl)prop-
2-en-1-one (3c). Yield: 87%; M.p. 202–204∘C; FT-IR (KBr,
cm−1): 1666 (C=O), 1610 (C=C); 1H-NMR (400 MHz,
DMSO-d ), ppm: 8.78 (s, 1H, 5-H), 8.37–8.27 (m, 13-H, 15-H,
6
2.3.2. MTT Assay. e synthetic chalcone derivatives were
tested for their antitumor activities against different type
cancer cell lines (PC-3 and MCF-7) using 3-(4,5-dimethyl-
thiazol–2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay
method. e pale-yellow tetrazolium salt, MTT, was trans-
formed by active mitochondria to form a dark blue formazan
that was determined by a microplate reader [37]. e MTT
method provides a simple way to detect living and growing
cells without using radioactivity.
17-H), 8.13 (s, 1H, 7-H), 8.08 (d, 1H, ꢄ = 15.6 Hz, 11-H), 7.92
(d, 1H, ꢄ = 16 Hz, 10-H), 7.78–7.68 (m, 3H, 3-H, 2-H, 16-H);
13C-NMR (400 MHz, DMSO-d ): 178.73, 154.67, 154.40,
6
148.95, 141.86, 136.66, 135.70, 131.87, 130.92, 129.57, 126.59,
125.43, 124.88, 123.51, 116.85, 115.39, 114.93; Anal. Calc.; % C,
54.86; H, 2.71; N, 3.76 Found: % C, 54.90; H, 2.76; N, 3.75.
(2E)-1-(5-Bromo-1-benzofuran-2-yl)-3-[4-(dimethylamino)-
phenyl]prop-2-en-1-one (3d). Yield: 70%; M.p. 179–181∘C;
FT-IR (KBr, cm−1): 1646 (C=O), 1579 (C=C); 1H-NMR
When the cells were confluent, they were removed from
the flasks using trypsin-EDTA solution and were seeded in
(400 MHz, DMSO-d ), ppm: 8.10 (s, 2H, 5-H, 7-H), 7.78–7.56
6
3
96-well plates such that there were 15 × 10 cells in each well.
(m, 6H, 3-H, 2-H, 13-H, 17-H, 10-H, 11-H), 6.77 (d, 1H,
ꢄ = 2.8 Hz, 14-H), 6.75 (d, 1H, ꢄ = 3.6 Hz, 16-H), 3.02 (s,
6H, CH ); 13C-NMR (400 MHz, DMSO-d ): 178.52, 155.35,
e plates were incubated for 24 h at 37∘C. Afer treatment
of these cancer cells with DMSO (for positive control group)
and different concentrations (1, 5, 25, 50, and 100 ꢃM) of
chalcone compounds (D1, 3a–j) in DMSO, the cells then
3
6
154.31, 152.75, 145.69, 131.61, 131.10, 129.85, 126.24, 122.00,
116.64, 115.98, 114.83, 112.98, 112.22, 40.56–39.31; Anal. Calc.;
% C, 61.64; H, 4.36; N, 3.78 Found: % C, 61.40; H, 3.31; N,
3.80.
were incubated for 24 h at 37∘C in 5% CO humidified
2
incubator. MTT solution (0.5 mg/mL) was prepared from the
MTT stock solution in sterile PBS and was added to each
well and the plates were then incubated for 3 h afer the
incubation for 24 h with chalcone compounds. Afer that,
DMSO and the optical density of the cells were determined by
an ELISA reader (Synergy HT, USA) at 550 nm wavelength.
e averages of the absorbance values were recorded by
reading the control wells that were considered as 100%. e
values of absorbance achieved from chalcone compounds
and solvent (DMSO) added wells were proportioned to the
control values, and the percentages of cell viability were
determined. e tests were reiterated ten times at several days
[38].
(2E)-1-(5-Bromo-1-benzofuran-2-yl)-3-(2-furyl)prop-2-en-1-
one (3e). Yield: 83%; M.p. 170–172∘C; FT-IR (KBr, cm−1): 1658
(C=O), 1596 (C=C); 1H-NMR (400 MHz, DMSO-d ), ppm:
6
8.03–7.96 (m, 3H, 5-H, 7-H, 15-H), 7.74–7.62 (m, 3H, 3-H,
2-H, 11-H), 7.55–7.40 (d, 1H, ꢄ = 15.2 Hz, 10-H), 7.14 (s, 1H,
13-H), 6.71 (s, 1H, 14-H); 13C-NMR (400 MHz, DMSO-d ):
6
178.56, 154.54, 154.41, 151.34, 147.15, 131.48, 130.78, 129.65,
126.37, 118.73, 118.50, 116.72, 114.85, 114.57, 113.77; Anal. Calc.;
% C, 56.81; H, 2.86 Found: % C, 56.75; H, 2.90.
(2E)-1-(5-Bromo-1-benzofuran-2-yl)-3-(2-thienyl)prop-2-en-
1-one (3f ). Yield: 83%; M.p. 168–170∘C; FT-IR (KBr, cm−1):
1
1660 (C=O), 1602 (C=C); H-NMR (400 MHz, DMSO-d ),
6
2.4. Statistical Analyses. Quantitative data are expressed as
mean standard deviation (SD). Normal distribution was
confirmed using Kolmogorov-Smirnov test. Quantitative
data were analyzed using Kruskal-Wallis ꢅ test following
Mann-Whitney ꢆ test with Bonferroni adjustment as a post
hoc test. All ꢀ values < 0.05 were considered as statistically
significant. All analyses were done by IBM SPSS Statistics 22.0
ppm: 8.17 (s, 1H, 5-H), 8.09 (s, 1H, 7-H), 8.02 (d, 1H, ꢄ = 15.6,
11-H), 7.91–7.67 (m, 4H, 3-H, 2-H, 15-H and 13-H), 7.51 (d, 1H,
ꢄ = 15.2 Hz, 10-H), 7.23 (dd, 1H, 14-H); 13C-NMR (400 MHz,
DMSO-d ): 178.54, 154.53, 154.48, 139.86, 137.27, 134.10,
6
131.64, 131.54, 129.69, 129.36, 126.42, 120.35, 116.76, 114.90,
114.05; Anal. Calc.; % C, 56.81; H, 2.86 Found: % C, 56.75; H,
2.90.
for Windows. e log IC values were determined by using
50
% cell viability values of compounds by GraphPad Prism 6
program.
2.3. In Vitro Antitumor Activity
2.3.1. Cell Culture. e cell lines of human breast cancer
(MCF-7) and human prostate cancer (PC-3) were employed
in our study. e PC-3 and MCF-7 cell lines were retrieved
from American Type Culture Collection (ATCC). MCF-7 and
PC-3 cells were fed with DMEM medium (supplemented
with 4500 mg/L glucose, 10% FBS, 100 U/mL penicillin, and
0.1 mg/mL streptomycin added) in 75 cm2 culture flasks
and RPMI-1640 medium (supplemented 10% FBS, 100 U/mL
penicillin, and 0.1 mg/mL streptomycin added), respectively.
A humidified carbon dioxide incubator (5% CO + 95% O ;
3. Results and Discussion
e new 1-(5-bromo-1-benzofuran-2-yl)ethanone was
obtained from the reaction of 5-bromosalicylaldehyde and 1-
chloroacetone. A series of chalcones (3a–f) were synthesized
by condensation of 1-(5-bromo-1-benzofuran-2-yl)ethanone
and various aromatic aldehydes (2a–f) (Scheme 2). For the
synthesis of chalcones, the most common route is the base-
catalyzed Claisen-Schmidt reaction involving condensation
2
2