2
of 11
HOSNY ET AL.
The wide applications of isoniazid and thiosemi-
carbazide derivatives prompted us to synthesize and
2.3 | Deconvolution analysis of IR spectra
study the cytotoxicity of N‐ethyl‐2‐isonicotinoylhydra-
IR spectra deconvolution analyses were carried out using
[9]
[14]
zine‐1‐carbothioamide,
N‐(2‐isonicotinoyl hydrazine
Peak Fit program.
The spectra were corrected for the
[10]
carbonothioyl)benzamide, 2‐isonicotinoyl‐N‐phenylhy-
dark current noises and background. The Gaussian peaks
exhibited the best‐fitted data and the full width at half
maximum, the intensity and position were adjusted auto-
matically on the basis of the minimization of the devia-
[
11]
drazine‐1‐carboxamide
and N‐benzoyl‐2‐isonicotinoyl-
[
12]
hydrazine‐1‐carboxamide
ligands and some of their
metal complexes.
[15,16]
Thus, on continuation to the efforts of looking for new
derivatives of isonicotinic thiosemicarbazides with
promising anti‐cancer activity, this work presents the
synthesize and characterization of a new ligand, 2‐
isonicotinoyl‐N‐phenylhydrazine‐1‐carbothioamide and
its metal complexes. To shed some light on the possible
applications, the cytotoxicity and the optical band gap
were tested. The ligand has very strong cytotoxicity
against both HCT‐116 and HEPG‐2 cell lines. Further-
more, the present compounds, are semi‐conductors.
tions between experimental and simulated spectrum.
2.4 | Synthesis of the ligand
Phenylisothiocyanate (0.01 mol) was added to
isonicotinic hydrazide (0.01 mol) in 20 mL absolute etha-
nol dropwise and the reaction mixture was refluxed for
1
hr. White crystals were isolated after cooling to room
temperature; filtered off, washed with ethanol and dried
in air. Yield: 85%, m.p.: 184 °C.
2
2
| EXPERIMENTAL
.1 | Reagents
2
.5 | Synthesis of the metal complexes
To 30 ml hot ethanolic solution of the ligand (0.01 mol),
equivalent amounts(0.01 mol) of Co (II), Cu (II), Ni (II)
or Zn (II) acetates in 25 ml absolute ethanol were added
dropwise with constant stirring. The reaction mixtures
were refluxed for 2 hr, where colored precipitates were
isolated on reflux. The precipitates were filtered off,
washed successfully with ethanol, ether and dried at
room temperature. Elemental analysis data and colors
for the complexes are given in Table 1.
Phenylisothiocyanate (98.0%) and isonicotinic hydrazide
(99.0%) were purchased from Sigma‐Aldrich. Co (II), Cu
(II), Ni (II) and Zn (II) acetate salts were purchased from
Merck. Colorectal (HCT‐116) and Hepatocellular (HePG‐
) carcinoma were obtained from ATCC. The reagents,
Fetal Bovine serum purchased from GIBCO, UK. RPMI‐
640 medium, MTT and 5‐fluorouracil were obtained
from Sigma.
2
1
2.2 | Measurements
2.6 | Cytotoxicity assay
The carbon and hydrogen contents were determined by
Perkin‐Elmer model 2400 CHN analyzer. The metals con-
tent were determined volumetrically using suitable indi-
The cell lines, HePG‐2 and HCT‐116, were used to deter-
mine the inhibitory effects of the compounds on cell
growth using the MTT assay. This colorimetric assay is
based on the conversion of the yellow tetrazolium
bromide (MTT) to a purple formazan derivative by mito-
chondrial succinate dehydrogenase in viable cells. Cell
lines were cultured in RPMI‐1640 medium with 10% fetal
bovine serum. Antibiotics added were 100 units/ml Pen-
icillin and 100 μg/ml Streptomycin at 37 °C in a 5% CO2
incubator. The cell lines were seeded in a 96‐well plate at
[13]
cators.
The magnetic susceptibilities were measured
using a Sherwood Scientific magnetic balance. Molar
conductivities were determined on an YSI model 32 con-
ductivity bridge. The FT‐IR spectra were recorded, as KBr
discs, on a Thermo‐Nicolet IS10 spectrometer. Electronic
spectra measurements were carried out on Unicam UV/
Vis., spectrometer UV2 using1 cm Silica cells. The NMR
1
13
4
H and C spectra of the ligand and its Zn (II) complex
a density of 1.0x10 cells/well at 37 °C for 48 hr under 5%
were recorded on Bruker Ascend 400 MHz. ESR spectra
of the Cu (II) complex were measured at room tempera-
ture using Brucker E 500 ESR spectrometer (9.808 GHz,
CO . After incubation, different concentration of the
2
compounds under investigation were added to the cells
and incubated for 24 hr. After 24 h treatment, 20 μl of
MTT solution at 5 mg/ml added and incubated for 4 hr.
Dimethyl sulfoxide (DMSO), 100 μL, is added into each
well to dissolve the purple formazan formed. The colori-
metric assay recorded at absorbance of 570 nm using a
1
2
00 kHz field modulation) from 480 to 6480 Gauss in a
mm quartz capillary. The thermal analysis (TG) were
carried out using Shimadzu model 50 at heating rate
0 °C/min and the nitrogen flow rate 20 ml/min.
1