Unravelling the anticancer potency of 1,2,4-triazole-N-arylamide hybrids through inhibition of STAT3: synthesis and in silico mechanistic studies

Article abstract of DOI:10.1007/s11030-020-10131-0

Abstract: The discovery of potent STAT3 inhibitors has gained noteworthy impetus in the last decade. In line with this trend, considering the proven biological importance of 1,2,4-triazoles, herein, we are reporting the design, synthesis, pharmacokinetic profiles, and in vitro anticancer activity of novel C3-linked 1,2,4-triazole-N-arylamide hybrids and their in silico proposed mechanism of action via inhibition of STAT3. The 1,2,4-triazole scaffold was selected as a privilege ring system that is embedded in core structures of a variety of anticancer drugs which are either in clinical use or still under clinical trials. The designed 1,2,4-triazole derivatives were synthesized by linking the triazole-thione moiety through amide hydrophilic linkers with diverse lipophilic fragments. In silico study to predict cytotoxicity of the new hybrids against different kinds of human cancer cell lines as well as the non-tumor cells was conducted. The multidrug-resistant human breast adenocarcinoma cells (MDA-MB-231) was found most susceptible to the cytotoxic effect of synthesized compounds and hence were selected to evaluate the in vitro anticancer activity. Four of the designed derivatives showed promising cytotoxicity effects against selected cancer cells, among which compound 12 showed the highest potency (IC₅₀ = 3.61?μM), followed by 21 which displayed IC₅₀ value of 3.93?μM. Also, compounds 14 and 23 revealed equipotent activity with the reference cytotoxic agent doxorubicin. To reinforce these observations, the obtained data of in vitro cytotoxicity have been validated in terms of ligand–protein interaction and new compounds were analyzed for ADMET properties to evaluate their potential to build up as good drug candidates. This study led us to identify two novel C3-linked 1,2,4-triazole-N-arylamide hybrids of interesting antiproliferative potentials as probable lead inhibitors of STAT3 with promising pharmacokinetic profiles. Graphic abstract: [Figure not available: see fulltext.]

Full text of DOI:10.1007/s11030-020-10131-0

Molecular Diversity
https://doi.org/10.1007/s11030-020-10131-0
ORIGINAL ARTICLE
Unravelling the anticancer potency of 1,2,4‑triazole‑N‑arylamide
hybrids through inhibition of STAT3: synthesis and in silico
mechanistic studies
Abdallah Turky1 · Ashraf H. Bayoumi1 · Farag F. Sherbiny1,2 · Khaled El‑Adl3,4 · Hamada S. Abulkhair1,5
Received: 6 July 2020 / Accepted: 6 August 2020
© Springer Nature Switzerland AG 2020
Abstract
The discovery of potent STAT3 inhibitors has gained noteworthy impetus in the last decade. In line with this trend, consid-
ering the proven biological importance of 1,2,4-triazoles, herein, we are reporting the design, synthesis, pharmacokinetic
profles, and in vitro anticancer activity of novel C3-linked 1,2,4-triazole-N-arylamide hybrids and their in silico proposed
mechanism of action via inhibition of STAT3. The 1,2,4-triazole scafold was selected as a privilege ring system that is
embedded in core structures of a variety of anticancer drugs which are either in clinical use or still under clinical trials.
The designed 1,2,4-triazole derivatives were synthesized by linking the triazole-thione moiety through amide hydrophilic
linkers with diverse lipophilic fragments. In silico study to predict cytotoxicity of the new hybrids against diferent kinds
of human cancer cell lines as well as the non-tumor cells was conducted. The multidrug-resistant human breast adenocarci-
noma cells (MDA-MB-231) was found most susceptible to the cytotoxic efect of synthesized compounds and hence were
selected to evaluate the in vitro anticancer activity. Four of the designed derivatives showed promising cytotoxicity efects
against selected cancer cells, among which compound 12 showed the highest potency (IC50 =3.61 µM), followed by 21
which displayed IC50 value of 3.93 µM. Also, compounds 14 and 23 revealed equipotent activity with the reference cytotoxic
agent doxorubicin. To reinforce these observations, the obtained data of in vitro cytotoxicity have been validated in terms of
ligand–protein interaction and new compounds were analyzed for ADMET properties to evaluate their potential to build up
as good drug candidates. This study led us to identify two novel C3-linked 1,2,4-triazole-N-arylamide hybrids of interesting
antiproliferative potentials as probable lead inhibitors of STAT3 with promising pharmacokinetic profles.
Electronic supplementary material The online version of this
article (https://doi.org/10.1007/s11030-020-10131-0) contains
supplementary material, which is available to authorized users.
* Hamada S. Abulkhair
hamadaorganic@azhar.edu.eg; habulkhair@horus.edu.eg
1
Pharmaceutical Organic Chemistry Department, Faculty
of Pharmacy, Al-Azhar University, Nasr City, Cairo 11884,
Egypt
2
Pharmaceutical Organic Chemistry Department, College
of Pharmacy, Misr University for Science and Technology
(MUST), 6th October City, Egypt
3
Department of Pharmaceutical Chemistry, Faculty
of Pharmacy, Al-Azhar University, Cairo, Egypt
4
Department of Pharmaceutical Chemistry, Faculty
of Pharmacy, Heliopolis University for Sustainable
Development, Cairo, Egypt
5
Pharmaceutical Chemistry Department, Faculty of Pharmacy,
Horus University - Egypt, International Costal Road,
New Damietta, Egypt
Vol.:(0123456789)
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Molecular Diversity
Graphic abstract
Keywords 1,2,4-Triazoles · Anticancer · STAT3 · Docking · Pharmacokinetic
in cancer [4]. Mammals contain seven types of these pro-
teins: STAT1, STAT2, STAT3, STAT4, STAT5a, STAT5b,
and STAT6 [5]. Among these seven protein types, STAT3
is a multifunctional member involved in the acute phase
response, evolution, cell progression and differentia-
tion, immunity, hematopoiesis, and even tumor survival
[6]. STAT3 proteins could be activated by cytokines and
growth factors [7]. Upon excitation by cytokines or one
of the growth factors, STAT3 is phosphorylated by spe-
cifc kinases, dimerize, and regulate gene expression by
the phosphorylated dimer [8]. While healthy cells display
transient physiologic STAT3 activation under the efect
of strict regulation by inhibitory molecules, tumor cells
depend on the constitutive stimulation of STAT3 for its
survival [9]. In addition, the ectopic expression of STAT3
alone is enough for aberrant cell transformation, given
Introduction
Cancer is characterized by an uncontrolled multiplica-
tion of abnormal cells and remains one of the top leading
causes of death worldwide. Up to date, more than 150
anticancer agents have been approved [1]. However, severe
drug toxicity and resistance of malignant tumors to clini-
cally used drugs are still major obstacles to efective chem-
otherapeutics, making the urgent need of identifying new
anticancer drugs with lower side efects and higher ef-
cacy [2]. The signal transducer and activator of transcrip-
tion (STAT) proteins are a family of cytoplasmic transcrip-
tion factors that have the ability to bind with DNA and
to induce the transcription of specifc genes [3]. Accord-
ingly, they play a crucial role in multiple cellular path-
ways and are frequently dysregulated or over-expressed
1 3

Molecular Diversity
its necessity for tumorigenesis [3]. Consequently, STAT3
proteins have recently emerged as an attractive therapeutic
target in the development of anticancer agents [8]. Mis-
regulation of STAT3 signaling pathway leads to its overex-
pression in diferent types of malignant cells including the
Multidrug-resistant human breast adenocarcinoma (MDA-
MB-231) [10, 11] and hepatocellular carcinoma [12, 13].
1,2,4-Triazoles are one of the extremely considerable
nitrogen-containing scafolds in the feld of medicinal chem-
istry because of their diverse biological activities, particu-
larly as anticancer [14–16]. Compounds belonging to this
class possess the ability to form a variety of non-covalent
interactions with diferent biological targets through hydro-
phobic interactions, hydrogen bonding, van der Waals
forces, and dipole–dipole interaction [17]. Some 1,2,4-tria-
zole incorporating compounds such as 3-nitro-1,2,4-tri-
azole analogue of [18F]FMISO ([18F]3-NTR, 1) are cur-
rently under clinical evaluation for management of cancer
concomitant hypoxia [18]. Also, indolyltriazolethione and
1,2,4-triazole-3-ylthioacetamide derivatives (2 and 3) dem-
onstrated signifcant antiproliferative activity in models of
MCF-7 and PC-3 cells, respectively, by activation of apopto-
sis and increasing the caspase-3 activity [19, 20]. Structural
alteration of these scafolds may result in the identifcation
of new improved chemotherapeutic agents with better phar-
macological properties.
efect [24, 25]. 1,2,4-Triazole derivatives 4 and 5 with
S-substituted acetamide moiety (Fig. 1) proved as poten-
tial cytotoxic against HT-29 and MDA-MB-231 cell
lines, respectively, [15, 22]. Furthermore, an analogous
1,3,4-oxadiazole with an amide linker (compound 6) has
been identifed as a STAT3 dimerization inhibitor [26].
Last but not least, compound 7 showed potent antican-
cer activity and has recently identifed as an inhibitor
of STAT3 signaling through direct binding with the SH
domain in melanoma cancer cells [27].
The resistance of breast cancer against chemotherapeu-
tics remains a major obstacle in the management of such
cancer type [28]. MDA-MB-231 cells have been recently
documented for their extreme multidrug resistance [28,
29]. Monotherapy for the treatment of breast cancer is
insufcient to eradicate the disease, and hence, there is an
unmet need for potent combinatorial chemotherapeutics.
Hybrid molecules with two or more diferent pharmacoph-
ores may have the potential to decrease the severity of side
efects and defeat the drug resistance. Hybrids may also
own multiple action mechanisms. It is worth noticing that
several hybrid molecules are under diferent phase clini-
cal trials for the treatment of various diseases including
those which are drug-resistant [30], revealing molecular
hybridization is a useful strategy to develop novel drugs.
Obviously, it is conceivable that molecular hybridization
of 1,2,4-triazole framework with the N-arylacetamide or
N-arylpropanamide has the potential to provide new anti-
cancer candidates with the possibility of lower toxicity
and higher efcacy.
Over the past decade, several molecules possessing
N-arylacetamide moiety have been synthesized as useful
chemotherapeutics with good cytotoxic activity [20–23].
Also, the N-arylpropanamide linker has been embedded in
many reported compounds with a remarkable anticancer
Fig. 1 Structure of representative 1,2,4-triazole and analogous oxadiazole derivatives incorporating N-arylamide moieties with potent anticancer
and STAT3 inhibitory potential
1 3

Molecular Diversity
N-arylamide linker to investigate the efect of such sub-
stitution pattern on the cytotoxicity of the designed com-
pounds. All the synthesized compounds were evaluated for
their in vitro cytotoxic activity against the chemotherapeutic
resistant human breast adenocarcinoma (MDA-MB-231).
In addition, the structure–activity relationship of the syn-
thesized compounds was illustrated based on the results of
cytotoxicity evaluation. As well, the possible underlying
mechanism of the most potent compounds was investigated
in silico to predict their binding afnity toward the active site
of STAT3 as a proposed therapeutic target of their cytotoxic
activity. MDA-MB-231 cell line was selected to evaluate the
cytotoxicity efect of new compounds after running an in
silico CLC-prediction to suggest the cytotoxicity against dif-
ferent types of cancer cells. Results of in silico cytotoxicity
prediction surprisingly showed that one of the top sensitive
cell lines to the action of our designed compounds was the
breast adenocarcinoma cell line (MDA-MB-231) which has
recently documented in a number of articles as a multid-
rug-resistant cancer cell [28]. To date, doxorubicin remains
one of the most commonly prescribed anthracyclines in the
treatment of breast cancer, including MDA-MB-231, and
hence used as a positive control. In addition, many shreds of
Rationale and structure‑based design
Based on the aforementioned facts and as a continuation of
our recent studies [31–33] on identifying new antiprolifera-
tive agents, molecular hybridization between 1,2,4-triazole
scafold and the N-arylacetamide or N-arylpropanamide
moiety was carried out in an attempt to get new anticancer
molecules with higher potency and lower toxicity. Molecular
hybridization is one of the well-established approaches in
drug design which involves the combination of pharmaco-
phores of more than one bioactive molecule [34]. This strat-
egy is expected to produce hybrid structures with improved
efcacy and lower toxicity compared to individual parent
drugs [35]. Here, inspired by the versatility of the 1,2,4-tria-
zole pharmacophoric ring scafold and the N-arylacetamide
or N-arylpropanamide moiety mentioned above, two novel
series of hybrid structures of C3-linked 1,2,4-triazole-N-ar-
ylamide hybrids were designed and synthesized by modi-
fying several structural aspects of the previously reported
STAT3 inhibitor (Fig. 2) to evaluate their anticancer activi-
ties. Diferent substitution patterns were introduced to both
the phenyl ring at C-5 of the triazole scafold and the ter-
minal aryl/heteroaryl ring attached with the hydrophilic
Fig. 2 Molecular hybridization of 1,2,4-triazole scafold with N-arylamide moieties
1 3

Molecular Diversity
evidence have recently documented for the overexpression of
STAT3 receptors in this type of cancer cells [10, 11]. Conse-
quently, MDA-MB-231 cell line was selected to conduct the
in vitro anticancer evaluation and to serve also as a model
of STAT3 receptor subtype. Finally, the pharmacokinetic
profles of the highest potent derivatives were examined to
evaluate their potential to build up as good drug candidates.
Results and discussion
Chemistry
Final target compounds of the present work were readily
achieved in four consecutive steps starting with commercially
available p-toluic and p-methoxybenzoic acids. The general
route adopted for the synthesis of the designed 1,2,4-tria-
zole derivatives is outlined in Scheme 1. Our convergent
synthesis approach starts with the preparation of N-aryl-
2-chloroacetamides and N-aryl-3-chloropropionamides
Scheme 1 Synthetic route of the designed new 1,2,4-triazole derivatives
1 3

Molecular Diversity
by the reaction of substituted anilines with 2-chloroace-
tylchloride or 3-chloropropionylchloride in the presence
of triethylamine [36, 37]. Substituted benzoic acids 8a, b
converted into their corresponding esters 8a, b by heating at
refux temperature in absolute ethanol containing a catalytic
amount of concentrated sulfuric acid. Nucleophilic substitu-
tion of the produced esters with hydrazine hydrate in ethanol
[38–40] was carried out to give hydrazide derivatives 10a,
b in relatively good yields and convenient purities. After-
ward, the latter hydrazide derivatives were allowed to react
with phenyl isothiocyanate under refux [41, 42] in an alco-
holic solution of potassium hydroxide to yield the potassium
salts of the prerequisite key intermediates 5-(aryl)-4-phe-
nyl-1,2,4-triazole-3-thiol (11a, b). The parent thioalcohols
of these potassium salts were readily achieved by the action
of dilute hydrochloric acid. Compounds 11a, b were fnally
coupled with the appropriate previously prepared 2-chloro-
N-arylacetamide or 3-chloro-N-arylpropanamide derivatives
in the presence of triethylamine to complete the synthesis of
target compounds 12–29 in relatively reasonable yields and
convenient purities.
expected m/z value. All the newly synthesized triazoles gave
elemental analysis data consistent with that calculated of
assigned structures. Collectively, these observations with the
disappearance of the SH signals in 1H NMR spectra of the
starting thioles 11a, b confrmed tethering the amide moiety
with triazole nucleus in the fnal compounds via S-linkage.
A reasonable mechanism for the conversion of the hydrazide
derivatives 10a, b into the corresponding 1,2,4-triazole-
3-thiols is shown in Fig. 3.
Evaluation of biological activity
Cytotoxicity assay
In order to decipher the cytotoxicity efect of new com-
pounds against diferent types of cancer cells, in silico
CLC-prediction system was used [43]. Using the appropri-
ate in silico technique helps in determining an experiment
of high efciency and reducing cost and implementation
time. Results of in silico CLC cytotoxicity prediction sur-
prisingly showed that one of the most susceptible cells to
the cytotoxic action of our designed compounds was the
multidrug-resistant human breast adenocarcinoma cell
(MDA-MB-231). Consequently, MDA-MB-231 cell line
was solely selected to conduct the in vitro anticancer eval-
uation. The in vitro anticancer activity on human breast
adenocarcinoma (MDA-MB-231) cancer cell line was per-
formed using MTT assay [44] and doxorubicin as a refer-
ence anticancer. Results of preliminary cytotoxic evaluation
Progress of chemical reactions was authenticated by
TLC methodology, and the fnal synthesized compounds
were purifed by column chromatography method. Struc-
tures and purities of new sets of 1,2,4-triazol-3-ylthio-N-ar-
ylacetamide and 1,2,4-triazol-3-ylthio-N-arylpropanamide
1
derivatives were confrmed based on their IR, LC–MS, H
NMR, and 13C NMR spectral data. Mass spectra of all the
new triazole-N-arylamide hybrid structures are characterized
by the presence of distinctive molecular ion peaks at the
Fig. 3 Proposed reaction mechanism for construction of 4H-1,2,4-triazole-3-thiol
1 3

Molecular Diversity
are shown in Table 1. The tabulated results revealed the
moderate to good cytotoxic activity of seven derivatives
with IC50 range of 3.61–17.05 µM. Compounds 12, 13, 21,
and 22 were the most potent with either equipotent or even
higher potency than that of the standard anticancer drug.
Compounds 12 and 21 showed more powerful cytotoxic-
ity efects than doxorubicin with IC50 values of 3.61 and
3.93 µM, respectively. Also, compounds 13 and 22 revealed
equipotent activity with doxorubicin against the selected
cancer cell line with IC50 value of 6.44 and 4.55 µM, respec-
tively. Higher doses (up to 87.02 µM) of derivatives 17, 24,
and 26 were needed for 50% inhibition of cell proliferation,
indicating mild activity of these derivatives.
Structure–activity relationship study
As mentioned before, the investigation of structure–activ-
ity relationship of newly synthesized triazoles as anticancer
agents is one of the main objectives of this work. SAR study
of new compounds revealed several common fndings: (1)
The nature of the substituent group at C-5 had no consider-
able impact on the activity against the tested cancer cell line.
Generally, compounds 12–20, incorporating a para-tolyl
substituent group at C-5 and compounds 21–29, incorporat-
ing para-methoxyphenyl substituent group at C-5, revealed
equipotent activity regardless of the nature of the para sub-
stituent; (2) conversely, the electronic nature of the terminal
aryl ring of lipophilic tail presented a considerable infuence
on the cytotoxicity. Compounds incorporating hydrogen
bonding acceptor fragments attached to the terminal aryl
ring displayed potent antitumor activity against the tested
cell line compared with other derivatives; (3) compounds
possessing monocyclic aryl substituent attached with the
acetamide linker at C-3 of the triazole core structure, such as
derivatives 12, 13, 15, 21, 18, 22, and 27, exhibited remark-
able and potent antitumor activity (IC50 =3.61–17.05 µM)
compared with similar compounds bearing naphthyl moie-
ties attached with the hydrophilic linkers, such as deriva-
tives 16 and 25 (IC50 values > 100 µM). Exceptionally,
2-((4-phenyl-5-(p-tolyl)-4H-1,2,4-triazol-3-yl)thio)-N-
(pyridin-2-yl)acetamide (17) is approximately twofold less
potent (IC50 =87.02 µM) against the tested cancer cell than
the analogous 2-((5-(4-methoxyphenyl)-4-phenyl-4H-1,2,4-
triazol-3-yl)thio)-N-(pyridin-2-yl)acetamide (26), which dis-
played IC50 value of 47.91 µM. Incorporation of the isosteric
pyridyl ring instead of the phenyl, as in case of 17, 18, 26,
and 27 led to slight decrease in antitumor activity (IC50 val-
ues, 17.05–77.60 μM); (4) the structure activity relation-
ships suggested that all compounds with an N-arylacetamide
moiety on C-3 position displayed better cytotoxic activity
than those substituted by N-arylpropanamide on the same
position. A summary of the structure–activity relationship
is presented in Fig. 4.
Table 1 In vitro anticancer activity of the designed 1,2,4-triazoles
against human breast adenocarcinoma (MDA-MB-231) cancer cell
line
Cpd.
R1
Ar
n
IC50 (µM)*
MDA-MB-231
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
CH3
4-BrC6H4
1
1
1
1
1
1
1
2
2
1
1
1
1
1
1
1
2
2
3.61 0.56
6.44 1.36
>100
10.96 0.65
>100
77.60 0.96
16.21 1.41
>100
CH3
4-ClC6H4
CH3
CH3
CH3
CH3
CH3
CH3
CH3
OCH3
OCH3
OCH3
OCH3
OCH3
OCH3
OCH3
OCH3
OCH3
4-CH3C6H4
4-OCH3C6H4
1-Naphthyl
2-Pyridinyl
5-Cl-pyridine-2-yl
4-BrC6H4
4-OCH3C6H4
4-BrC6H4
4-ClC6H4
4-CH3C6H4
4-OCH3C6H4
1-Naphthyl
2-Pyridinyl
5-Cl-pyridine-2-yl
4-BrC6H4
>100
3.93 0.27
4.55 0.55
>100
87.02 1.17
>100
47.91 0.72
17.05 1.01
>100
Molecular docking study
In the present work, a docking study was performed to elu-
cidate the binding modes of all the designed compounds
inside the binding pocket of the signal transducer and activa-
tor of transcription 3 (PDB ID: 6NJS). Docking study was
conducted using the MOE 2014.09 software to determine
the free energy and binding mode. Selection of the best
promising derivatives depended on both the perfect bind-
ing mode and the highest free energy of binding. The low-
est value of binding energy depicts the best conformational
position of the ligand within the active site of the target pro-
tein. Free energies of binding of all new compounds and the
4-OCH3C6H4
>100
4.50 0.26
Doxorubicin
Bold values indicate compounds with good activity and binding afnity
*Cytotoxicity was assayed by treating cells with the test compound
for 72 h and expressed as the concentration needed to inhibit 50% of
tumor cell proliferation (IC50). Data here are presented as the means
of fve independent experiments SD
1 3

Molecular Diversity
Fig. 4 Summary of SAR study of the synthesized 1,2,4-triazoles
Table 2 The binding free energies (ΔG, kcal/mol) of the target tria-
zoles and the co-crystallized ligand (SD-36) with the binding site
STAT3
para-substituents of terminal aryl rings attached with the
amide linkers. In fact, compounds other than 12, 13, 15, 18,
21, 22, and 27, which have low activity, (IC50 ≥47.91 μM)
all either do not contain hydrogen bond acceptor at para
positions in amide functional group or the linker is propana-
mide, while compounds 12, 13, 15, 18, 21, 22, and 27 (IC50
3.61–17.05 μM) have bromo, chloro, or methoxy substitu-
ents at para positions and the linker is acetamide rather than
propanamide.
Compound
ΔG (kcal/mol)
Compound
ΔG (kcal/mol)
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
−6.94
−7.14
−6.12
−6.67
−6.09
−6.07
−6.34
−6.01
−5.97
−6.98
22.
−7.09
−6.30
−6.24
−6.11
−6.32
−6.77
−6.14
−5.95
−8.25
23.
24.
25.
26.
As a result, compounds that hold a hydrogen bond accep-
tor group possess good inhibitory activity. From the in vitro
study, we suggested that the compounds 12, 13, 21, and 22
with hydrogen bond acceptor group at para-positions in
acetamide functionality display much higher activity than
other compounds. These compounds form key interactions
similar to the reported STAT3 degrader with the amino
acids Gln644, Tyr640, and Lys658. Binding modes of com-
pounds 12 and 13 in series A, as representative examples of
triazoles with hydrogen bond acceptors at the para position
of the terminal benzene ring, exhibited afnity values of
−6.94 and 7.14 kcal/mol, respectively. Obeying almost the
same interaction pattern of co-crystallized ligand SD-36,
the docked pose of 12 was stabilized by hydrogen bond of
the NH with Lys658 residue. The phenyl ring at C-5 has
involved in a sidewise arene-H interaction with Gln644 and
Tyr640 residues. Carbonyl group of compound 13 showed an
additional hydrogen bonding interaction with Tyr657 residue
(Fig. 5). Similarly, compounds 21 and 22 as representative
examples of series B showed similar binding modes with
that of SD-36, with afnity value of −6.98 and 7.09 kcal/
mol, respectively. The N-1 of triazole ring played as a hydro-
gen bond acceptor with the carboxylic group of Tyr657 and
Glu638 residues. The terminal phenyl rings formed arene-H
interactions with Lys658 and Pro639 residues.
27.
28.
29.
SD−36
Bold values indicate compounds with good activity and binding afnity
co-crystallized ligand (SD-36), a STAT3 degrader, are pre-
sented in Table 2. Binding mode of the co-crystallized ligand
SD-36 with the pocket of signal transducer and activator of
transcription 3 exhibited a binding energy of − 8.25 kcal/
mol. According to Bai et al. [45], key interactions for SD-36
degrader of STAT3 are as follows: (a) an extensive hydro-
gen bonding network between the phosphoric acid moiety of
SD-36 and the side chains of Arg609, Ser611, and Ser613;
(b) the fuorine atom of the difuoromethyl group forms a
hydrogen bond with Arg609; (c) two hydrogen bonding
interactions between the glutamine C=O and NH of SD-36
and Gln644 and Tyr640; (d) water-mediated hydrogen bonds
with the Tyr640’s OH and amide nitrogen of Lys658. From
the new compounds docked in STAT3, N-arylacetamides
with monocyclic aryl rings showed adequate spatial ori-
entations and distinct interaction patterns with the target
enzyme compared to other analyzed structures. As displayed
in Table 2, all the target compounds comprise the same
scafold (1,2,4-triazol-3-ylthio)-N-arylamide, but only the
changes are mainly in both the length of amide linkers and
Compounds 18 and 27, as examples of derivatives incor-
porating pyridyl moiety attached with acetamide linkers,
exhibited diferent virtual binding mode with that of SD-36.
Compound 18 revealed an afnity value of −6.34 kcal/mol
and showed three diferent interactions with the binding site
1 3

Molecular Diversity
Fig. 5 3D interactions of compounds 12 (upper left panel), 13 (upper right panel), 21 (lower left panel), and 22 (lower right panel) with the
active site of STAT3 (PDB ID: 6NJS)
of STAT3. These interactions involve two arene-H interac-
tions between the pyridine and triazole rings in the target
compounds and Pro639 and Tyr657 residues in STAT3,
respectively. The last interaction is in the form of a hydrogen
bond between the NH of acetamide linker with the carbonyl
oxygen of Ser636 residue.
of in vitro cytotoxicity data. These results indicated that
except for 16 and 25, all the studied triazole derivatives with
N-arylacetamide moiety revealed similar positions and ori-
entations inside the binding site of the STAT3. The intro-
duction of either a longer linker or a bulky aromatic ring,
like naphthalene, both decrease the afnity of the compound
for the STAT3 receptor. In addition, the results explain that
some of these compounds may have good binding afnities
to the receptor and the computed values refect the overall
trend. Furthermore, the present work spotlighted the triazole
moiety as an attractive scafold for obtaining potent STAT3
inhibitor.
Increasing the linker length at the C-3 position as in com-
pounds 19, 20, 28, and 29 displayed an undesirable efect
on the afnity for the receptor (Table 2). Also, replacing the
phenyl and pyridyl rings at C-3 with naphthyl moiety, as in
compounds 16 and 25, showed a similar unfavorable efect
on the afnity. In addition, the presence of such a bulky
substituent at C-3 may decrease the afnity of the last two
compounds due to failure of these compounds to accommo-
date the binding pocket of the receptor and thus the scafold
pushed out of the catalytic domain. The obtained result for
compound 16 is virtually the same as that of compound 25.
With − 6.19 kcal/mol free energy of binding, the binding
mode of 16 involves three arene-H interactions between the
triazole, phenyl, and naphthyl rings with Gln644, Tyr657,
and Glu638 residues, respectively.
Pharmacokinetic profling study
In the present study, an in silico computational study of
the representative C3-linked 1,2,4-triazole-N-arylamide
hybrids was performed for determining the surface area
and other physicochemical properties following the direc-
tions of Lipinski’s rule of fve [46]. Lipinski suggested that
the absorption of an orally administered compound is more
likely to be better if the molecule satisfes at least three of the
following rules: (1) H bond donors (OH, NH, and SH)≤5;
Collectively, the obtained results of binding free ener-
gies (ΔG) and binding studies were consistent with results
1 3

Molecular Diversity
(2) H bond acceptors (N, O, and S atoms)≤10; (3) molecu-
lar weight<500; (iv) logP<5. Compounds violating more
than one of these rules could not have good bioavailability.
While the reference anticancer drug doxorubicin violated
three of Lipinski’s rules, all the highest active derivatives in
this study violated only one (LogP) except 15 which, gratify-
ingly, satisfed all the Lipinski’s rules. All derivatives have
a number of hydrogen bond acceptors between 5 and 6 and
only 1 hydrogen bond donor, and these values agree with
Lipinski’s rules.
in terms of the total clearance, a parameter related to the
bioavailability, and is signifcant in deciding dose inter-
vals. Produced data demonstrated that 15 and doxorubicin
revealed the highest total clearance values (0.143 and 0.987,
respectively), when compared to other ligands, especially
21, which showed the lowest total clearance value (−0.066).
Thus, 15 and doxorubicin could be excreted faster and con-
sequently require shorter dosing intervals. Unlike doxoru-
bicin, compound 21 showed a slower clearance rate, which
means the preference of longer dosing intervals for the later.
The last parameter analyzed in the pharmacokinetic profle
of our newly synthesized triazoles is the hepatotoxicity. As
shown in Table 3, all new ligands as well as doxorubicin
shared the drawback of hepatotoxic efects. Gratifyingly,
our designed compounds showed better tolerability (~0.88)
compared with 0.081 for doxorubicin. Finally, the oral acute
toxic doses of the designed compounds (LD50) are higher
than those of the reference drug (~ 2.80 compared with
2.40).
Also, absorption, distribution, metabolism, excretion, and
toxicity (ADMET) profles of the new synthesized 1,2,4-tri-
azole-N-arylamide hybrids were tentatively evaluated to ana-
lyze its potential to build up as good oral drug candidates.
The compound’s pharmacokinetic profle detects how it
would be absorbed, distributed, metabolized, and excreted
(ADME). While optimal binding of a drug with its therapeu-
tic protein target is critical, ensuring that it will arrive this
target in an adequate concentration to produce the biologi-
cal efect is also essential. Prediction of ADMET profles
is conducted using the pkCSM descriptors algorithm pro-
tocol [47]. Two main structural features correlate properly
with PK properties, the two-dimensional polar surface area
(PSA_2D) and the lipophilicity levels (LogP). Absorption
of a drug depends on a number of factors including mem-
brane permeability, intestinal absorption, skin permeability,
and P-glycoprotein substrate or inhibitor. Drug distribution
depends on the volume of distribution (VDss), the blood
brain barrier permeability (logBB), and CNS permeability.
Metabolism is predicted depending on the CYP models for
substrate or inhibition. Excretion is predicted based on the
total clearance and the renal OCT2 substrate. Toxicity of the
drugs is predicted depended on AMES toxicity, hERG inhi-
bition, hepatotoxicity, and skin sensitization. These param-
eters were all calculated for the highest potent triazoles
12, 13, 15, 18, 21, and 22 as well as to reference marketed
anticancer drug doxorubicin. After calculating the ADMET
properties (Table 3), we can suggest that the highest potent
derivatives have the preference of better intestinal absorption
in human over doxorubicin (90.842–93.166) compared with
62.372 in case of doxorubicin. This advantage is attributed
to the greater lipophilicity of the designed ligands, which
would make it easy to go along biological membranes [48].
Accordingly, they may have considerable good bioavailabil-
ity after oral administration in experimental testing. Analyz-
ing the CNS permeability, N-arylacetamide derivatives 12
and 13 displayed the highest ability to penetrate the CNS
(CNS permeability>−2.0), while doxorubicin is unable to
penetrate (CNS permeability<−4.0). It was also clear that
in contrast to doxorubicin, all compounds could inhibit the
cytochrome P3A4, the main cytochrome involved in drug
metabolism. This is possibly due to the higher lipophilic-
ity of our designed ligands. The excretion was evaluated
Conclusion
In the present study, we are reporting the design, synthesis,
in vitro anticancer evaluation, of 1,2,4-triazole-N-arylamide
hybrids in a model of MDA-MB-231 cell line. In silico dock-
ing and pharmacokinetic profling studies were also con-
ducted to determine the potential of new compounds to build
up as good oral drug candidates. Our target compounds were
designed based on molecular hybridization of the 1,2,4-tria-
zole scafold of [18F]3-NTR with N-arylamide moiety pre-
sented in a wide variety of anticancer agents. The possible
underlying mechanism of action of the highest active deriva-
tives was explained in terms of the in silico binding afnity
toward STAT3 receptor as a proposed potential therapeutic
target. This study led us to the identifcation of four novel
C3-linked 1,2,4-triazole-N-arylamide hybrids of interest-
ing antiproliferative activity against the multidrug-resistant
human breast adenocarcinoma cells (MDA-MB-231) at low
micromolar concentration, and probable STAT3 inhibitory
potentials. Further research is in progress to identify the
accurate mechanisms through which triazole-N-arylamide
may impact antiproliferative activity and to elucidate in
depth the structure–activity relationships after more cavern-
ous structure optimization.
Experimental section
General
Melting points were measured using electrothermal (Stuart
SMP30) apparatus and were uncorrected. Infrared spectra
1 3

Molecular Diversity
Table 3 ADMET profle of the
six most active compounds and
doxorubicin
Parameter
12
13
15
18
21
22
Dox.
Molecular properties
Molecular weight
LogP
479.403 434.952 430.533 435.94 495.402 450.951 543.525
5.73602 5.62692 4.98212 5.02192 5.4362 5.3271 0.0013
Rotatable bonds
Acceptors
Donors
6
5
1
6
5
1
7
6
1
6
6
1
7
6
1
7
6
1
5
12
6
Surface area
187.226 183.662 184.837 182.882 192.340 188.776 222.081
Absorption
Water solubility
Caco2 permeability
Intestinal abs. (human)
Skin Permeability
P-glycoprotein substrate
P-glycoprotein I inhibitor
P-glycoprotein II inhibitor
Distribution
−5.178 −5.158 −4.699 −4.377 −4.635 −4.619 −2.915
0.978
0.98
1.066
1.106
1.067
1.07
0.457
90.842 90.909 93.386 93.166 92.024 92.091 62.372
−2.736 −2.736 −2.736 −2.736 −2.736 −2.736 −2.735
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
VDss (human)
−0.038 −0.052 −0.162 0.069
−0.105 −0.118 1.647
0.23 0.23 0.215
−0.736 −0.591 −0.583 −1.379
−2.012 −2.035 −4.307
Fraction unbound (human)
BBB permeability
CNS permeability
Metabolism
0.216
0.311
−1.73
0.216
0.312
0.238
−0.42
0.238
−1.752 −2.061 −2.11
CYP2D6 substrate
CYP3A4 substrate
CYP1A2 inhibitor
CYP2C19 inhibitor
CYP2C9 inhibitor
CYP2D6 inhibitor
CYP3A4 inhibitor
Excretion
No
No
No
No
No
No
Yes
No
Yes
Yes
No
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Total clearance
Renal OCT2 substrate
Toxicity
−0.042 −0.021 0.143
0.081
No
−0.066 −0.044 0.987
No
No
No
No
No
No
AMES toxicity
No
0.893
No
Yes
0.892
No
No
0.879
No
No
0.900
No
No
0.896
No
No
0.895
No
No
0.081
No
Max. tolerated dose (human)
hERG I inhibitor
hERG II inhibitor
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Oral rat acute toxicity (LD50
)
2.899
2.901
0.088
Yes
2.921
0.367
Yes
2.795
0.297
Yes
2.913
0.057
Yes
2.914
0.068
Yes
2.408
3.339
Yes
Oral rat chronic toxicity (LOAEL) 0.078
Hepatotoxicity
Yes
Skin sensitization
T. Pyriformis toxicity
Minnow toxicity
No
0.286
No
0.286
No
0.286
No
0.286
No
0.286
No
0.286
No
0.285
−0.287 −0.141 −0.583 −1.286 −0.771 −0.625 4.412
were recorded on Pye Unicam SP 1000 IR spectrophotom-
eter at the Pharmaceutical Analytical Unit, Faculty of Phar-
macy, Al-Azhar University. 1H NMR and 13C NMR spectra
were recorded in DMSO-d6 at 300 and 100 MHz, respec-
tively, on a Varian Mercury VXR-300 NMR spectrometer
at NMR Lab, Faculty of Science, Cairo University. Chemi-
cal shifts were related to that of the solvent, and TMS was
used as an internal standard. Coupling constant and chemi-
cal shift values are mentioned in Hz and ppm, respectively.
Mass spectra and elemental analyses were carried out at
the Regional Center for Mycology and Biotechnology, Al-
Azhar University, Cairo, Egypt. The progress of reactions
was monitored with Merck silica gel IB2-F plates (0.25 mm
thickness) and was visualized under a UV lamp using
1 3

Molecular Diversity
diferent solvent systems as mobile phases. Reagents and
starting benzoic acid derivatives, hydrazine hydrate, phe-
nyl isothiocyanate, chloroacetyl chloride, chloropropionyl
chloride, 2-aminopyridine, 5-chloropyridine-2-amine, and
aniline derivatives were purchased from Aldrich chemical
company and were used as received. 2-Chloro-N-arylacet-
amides and 3-chloro-N-arylpropanamdedes were prepared
following reported procedures [25, 39]. Compounds 11a,
b were synthesized according to the direction of reported
procedures [16, 27, 49].
Anal. Calc. for C23H19BrN4OS (M.W.=479): C, 57.63; H,
4.00; N, 11.69; Found: C, 57.75; H, 4.14; N, 11.80%.
N‑(4‑Chlorophenyl)‑2‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑tria-
zol‑3‑yl)thio)acetamide (13) White solid (0.36 g, 83%);
mp = 235–237 °C; IR (KBr) νmax cm−1: 3428 (NH), 3078
(CH aromatic), 2961 (CH aliphatic), 1676 (C=O), 1520
General procedures for synthesis
of N‑aryl‑3‑((4‑phenyl‑5‑(aryl)‑4H‑1,2,4‑triazol‑3‑yl)
thio)acetamide/propenamide derivatives (12–29)
1
(C=C); H NMR (DMSO-d6) δ: 10.49 (brs, 1H, NH),
7.60 (d, J = 8.4 Hz, 2H), 7.55 (t, J = 8.4 Hz, 1H), 7.41 (d,
J=9.6 Hz, 2H), 7.36 (d, J=8.8 Hz, 2H), 7.23 (t, J=8.0 Hz,
2H), 7.15 (d, J=7.2 Hz, 2H), 7.13 (d, J=7.2 Hz, 2H), 4.17
(s, 2H, SCH2), 2.26 (s, 3H, CH3); 13C NMR (DMSO-d6) δ:
165.5, (C=O), 154.4, (triazole C-5), 151.6, (triazole C-3),
151.1, (N-phenyl C-1), 148.0, (NH-phenyl C-1), 139.5,
(NH-phenyl C-4), 138.2, (phenyl C-1, C-4), 133.8, (NH-
phenyl C-3, C-5), 130.0, (phenyl C-3, C-5), 125.3, (NH-
phenyl C-2, C-6), 123.6, (N-phenyl C-3, C-5), 120.6, (phe-
nyl C-2, C-6), 119.6, (N-phenyl C-4), 113.3, (N-phenyl C-2,
C-6), 36.7, (SCH2), 20.7, (CH3); MS (m/z, %): 434 (M+,
8.84%), 436 (M+2, 2.061%). Anal. Calc. for C23H19ClN4OS
(M.W.=454): C, 63.51; H, 4.40; N, 12.88; Found: C, 62.51;
H, 4.47; N, 13.01%.
As displayed in Scheme 1, the appropriate 5-(aryl)-4-phenyl-
4H-1,2,4-triazole-3-thiol derivatives 11a, b (0.001 mol) was
suspended in a solution of triethylamine (0.025 mol) in DMF
(30 mL). The right 2-chloro-N-arylacetamide or 3-chloro-
N-arylpropanamide derivative (0.011 mol) was added, and
the reaction mixture was heated to 90 °C for 8 h with con-
tinuous stirring. After the reaction was completed (moni-
tored by TLC), the mixture was allowed to cool and to stand
overnight. Later, after adding distilled cold water (100 mL),
the obtained solid products were collected through fltration,
washed with three potions of cold water (100 mL each) to
remove the side salt product triethylammonium chloride,
dried, crystallized from ethanol, and fnally purifed by
using column chromatography technique using hexane–ethyl
acetate as an eluent to aford pure 1,2,4-triazole derivatives
(12–29) in reasonable yields.
2‑((4‑Phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑triazol‑3‑yl)thio)‑N‑(p‑tolyl)
N‑(4‑Bromophenyl)‑2‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑tria-
acetamide (14) White solid (0.28 g, 68%); mp = 227–
229 °C; IR (KBr) νmax cm−1: 3422 (NH), 3070 (CH aro-
matic), 2988 (CH aliphatic), 1670 (C=O), 1461 (C=C);
1H NMR (DMSO-d6) δ: 10.23 (brs, 1H, NH), 7.55 (d,
J=1.6 Hz, 2H), 7.54 (t, J=2.0 Hz, 1H), 7.45 (d, J=7.6 Hz,
2H), 7.43 (d, J=8.4 Hz, 2H), 7.41 (t, J=3.6 Hz, 2H), 7.22
(d, J = 8.0 Hz, 2H), 7.10 (d, J= 8.8 Hz, 2H), 4.15 (s, 2H,
SCH2), 2.26 (s, 6H, 2CH3); 13C NMR (DMSO-d6) δ: 170.6,
(C=O), 154.3, (triazole C-5), 151.0, (triazole C-3), 144.2,
(N-phenyl C-1), 139.4, (NH-phenyl C-1), 133.8, (phenyl
C-4, N-phenyl C-4), 132.7, (phenyl C-1), 130.0, (NH-phenyl
C-3, C-5), 129.9, (phenyl C-3, C-5), 129.3, (N-phenyl C-3,
C-5), 128.5, (N-phenyl C-4), 127.7, (N-phenyl C-2, C-6),
127.5, (NH-phenyl C-2, C-6), 123.7, (phenyl C-2, C-6),
38.5, (SCH2), 21.1, (CH3), 20.7, (CH3); MS (m/z, %): 414
(M+, 3.12%). Anal. Calc. for C24H22N4OS (M.W. = 414):
zol‑3‑yl)thio)acetamide (12) White solid (0.35 g, 73%);
mp = 242–244 °C; IR (KBr) νmax cm−1: 3431 (NH), 3012
(CH aromatic), 2984 (CH aliphatic), 1675 (C=O), 1556
(C=C); 1H NMR (DMSO-d6) δ: 10.49 (brs, 1H, NH), 7.55–
7.40 (m, 9H), 7.23–7.13 (m, 4H), 4.17 (s, 2H, SCH2), 2.26
(s, 3H, CH3); 13C NMR (DMSO-d6) δ: 166.4, (C=O), 154.3,
(triazole C-5), 151.7, (triazole C-3), 151.3, (N-phenyl C-1),
148.2, (NH-phenyl C-1), 139.5, (phenyl C-4, N-phenyl C-4),
138.3, (phenyl C-1), 133.8, (NH-phenyl C-3, C-5), 130.0,
(phenyl C-3, C-5), 129.9, (N-phenyl C-3, C-5), 129.1, (NH-
phenyl C-4), 127.7, (N-phenyl C-2, C-6), 127.2, (NH-phenyl
C-2, C-6), 123.6, (phenyl C-2, C-6), 36.8, (SCH2), 20.8,
(CH3); MS (m/z, %): 479 (M+, 1.15%), 481 (M+2, 0.91%).
1 3

Molecular Diversity
C, 69.54; H, 5.35; N, 13.52; Found: C, 69.58; H, 5.51; N,
13.57%.
(M.W.=450): C, 71.98; H, 4.92; N, 12.44; Found: C, 72.05;
H, 5.00; N, 12.46%.
N‑(4‑Methoxyphenyl)‑2‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑tri-
2 ‑ ( ( 4 ‑ P h e n y l ‑ 5 ‑ ( p ‑ t o l y l ) ‑ 4 H ‑ 1 , 2 , 4 ‑ t r i a z o l ‑ 3 ‑ y l )
thio)‑N‑(pyridin‑2‑yl)acetamide (17) White solid (0.28 g,
71%); mp=238–240 °C; IR (KBr) νmax cm−1: 3420 (NH),
3026 (CH aromatic), 2856 (CH aliphatic), 1667 (C=O),
1533 (C=C); 1H NMR (DMSO-d6) δ: 10.49 (brs, 1H, NH),
7.58 (d, J=8.2 Hz, 2H), 7.54 (d, J=9.6 Hz, 1H), 7.51 (d,
J=9.6 Hz, 1H), 7.42 (t, J=8.2 Hz, 1H), 7.28 (t, J=8.2 Hz,
1H), 7.23 (t, J=8.2 Hz, 2H), 7.21 (d, J=7.2 Hz, 2H), 7.15
(d, J=7.4 Hz, 2H), 7.10 (t, J=7.4, 1H), 4.18 (s, 2H, SCH2),
2.29 (s, 3H, CH3); 13C NMR (DMSO-d6) δ: 168.8, (C=O),
144.8, (triazole C-5), 139.3, (Pyridyl C-2), 138.9, (triazole
C-3), 134.8, (Pyridyl C-6), 134.8, (N-phenyl C-1), 134.4,
(Pyridyl C-4), 132.3, (phenyl C-1), 129.5, (phenyl C-4),
129.0, (phenyl C-3, C-5), 127.5, (N-phenyl C-3, C-5), 124.0,
(N-phenyl C-4), 123.6, (N-phenyl C-2, C-6), 120.5, (phe-
nyl C-2, C-6), 120.2, (Pyridyl C-5), 117.5, (Pyridyl C-3),
37.5, (SCH2), 20.8, (CH3); Anal. Calc. for C22H19N5OS
(M.W.=401): C, 65.82; H, 4.77; N, 17.44; Found: C, 65.93;
H, 4.80; N, 17.48%.
azol‑3‑yl)thio)acetamide (15) White solid (0.33 g, 77%);
mp = 223–225 °C; IR (KBr) νmax cm−1: 3431 (NH), 3056
(CH aromatic), 2945 (CH aliphatic), 1680 (C=O), 1440
(C=C); 1H NMR (DMSO-d6) δ: 9.83 (brs, 1H, NH), 7.52 (d,
J=3.0 Hz, 2H), 7.48 (d, J=9.3 Hz, 1H), 7.44 (d, J=9.3 Hz,
2H), 7.25 (d, J=8.1 Hz, 2H), 7.15 (t, J=8.1 Hz, 2H), 6.87
(d, J = 9.3 Hz, 2H), 6.84 (d, J= 9.3 Hz, 2H), 3.71 (s, 2H,
SCH2), 2.82 (s, 3H, OCH3), 2.27 (s, 3H, CH3); 13C NMR
(DMSO-d6) δ: 168.4, (C=O), 160.1, (triazole C-5), 155.1,
(triazole C-3), 151.1, (N-phenyl C-1), 134.0, (NH-phenyl
C-1), 132.1, (phenyl C-4, N-phenyl C-4), 129.9, (phenyl
C-1), 129.8, (NH-phenyl C-3, C-5), 129.3, (phenyl C-3,
C-5), 127.7, (N-phenyl C-3, C-5), 120.5, (N-phenyl C-4),
118.9, (N-phenyl C-2, C-6), 114.0, (NH-phenyl C-2, C-6),
113.7, (phenyl C-2, C-6), 55.2, (OCH3), 35.8, (SCH2), 21.8,
(CH3); MS (m/z, %): 430 (M+, 10.29%). Anal. Calc. for
C24H22N4O2S (M.W. = 430): C, 66.96; H, 5.15; N, 13.01;
Found: C, 66.99; H, 5.19; N, 13.12%.
N‑(5‑Chloropyridin‑2‑yl)‑2‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4
N‑(Naphthalen‑1‑yl)‑2‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑tri-
‑triazol‑3‑yl)thio)acetamide (18) White solid (0.32 g, 74%);
mp = 239–241 °C; IR (KBr) νmax cm−1: 3419 (NH), 3029
(CH aromatic), 2886 (CH aliphatic), 1666 (C=O), 1531
(C=C); 1H NMR (DMSO-d6) δ: 10.38 (brs, 1H, NH), 7.56
(d, J = 2.1 Hz, 2H), 7.54 (d, J = 3.9 1H), 7.48 (d, J = 8.4,
1H), 7.44 (t, J=3.3, 1H), 7.42 (t, J=3.3 Hz, 2H), 7.40 (d,
J = 4.5 Hz, 2H), 7.36 (d, J = 3.9 Hz, 2H), 7.12 (t, J = 8.1,
1H), 4.18 (s, 2H, SCH2), 2.24 (s, 3H, CH3); 13C NMR
(DMSO-d6) δ: 168.7, (C=O), 144.8, (triazole C-5), 139.3,
(Pyridyl C-2), 138.9, (triazole C-3), 134.8, (Pyridyl C-6),
134.8, (N-phenyl C-1), 134.4, (Pyridyl C-4), 132.4, (phe-
nyl C-1), 129.6, (phenyl C-4), 129.0, (phenyl C-3, C-5),
127.5, (N-phenyl C-3, C-5), 124.0, (N-phenyl C-4), 123.7,
(N-phenyl C-2, C-6), 120.4, (phenyl C-2, C-6), 120.1, (Pyri-
dyl C-5), 117.6, (Pyridyl C-3), 37.6, (SCH2), 21.0, (CH3);
azol‑3‑yl)thio)acetamide (16) White solid (0.31 g, 69%);
mp = 231–233 °C; IR (KBr) νmax cm−1: 3451 (NH), 3031
(CH aromatic), 1674 (C=O), 1553 (C=C); 1H NMR
(DMSO-d6) δ: 10.32 (brs, 1H, NH), 7.79–7.42 (m, 10H),
7.25 (d, J=4.0 Hz, 2H), 7.15 (d, J=4.0 Hz, 2H), 4.33 (s,
2H, SCH2), 2.27, (s, 3H, OCH3); 13C NMR (DMSO-d6) δ:
170.2, (C=O), 155.5, (triazole C-5), 149.6, (triazole C-3),
145.3, (N-phenyl C-1), 137.2, (N-phenyl C-1), 134.4, (phe-
nyl C-4), 134.3, (naphthyl-C-4a), 131.1, (phenyl C-4),
129.2, (phenyl C-3, C-5), 128.6, (N-phenyl C-3, C-5), 128.3,
(N-phenyl C-6), 127.6, (naphthyl C-3), 127.4, (phenyl C-2,
C-6), 126.6, (N-phenyl C-2, C-6), 126.1, (naphthyl C-7),
125.7, (naphthyl C-8), 124.6, (naphthyl C-8a), 121.9, (naph-
thyl C-4), 107.2, (naphthyl C-2), 40.8, (SCH2), 22.3 (CH3);
MS (m/z, %): 450 (M+, 8.09%). Anal. Calc. for C27H22N4OS
1 3

Molecular Diversity
MS (m/z, %): 435 (M+, 1.17%), 437 (M+2, 0.47%). Anal.
Calc. for C22H18ClN5OS (M.W. =435): C, 60.62; H, 4.16;
N, 16.07; Found: C, 60.64; H, 4.19; N, 16.12%.
123.6, (phenyl C-2, C-6), 56.8 (OCH3), 33.3, (CH2CO),
29.4, (SCH2), 21.3, (CH3); MS (m/z, %): 493 (M+, 3.12%).
Anal. Calc. for C25H24N4O2S (M.W. = 444): C, 67.55; H,
5.44; N, 12.60; Found: C, 67.63; H, 5.48; N, 12.64%.
N‑(4‑Bromophenyl)‑3‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑tria-
N‑(4‑Bromophenyl)‑2‑((5‑(4‑methoxyphenyl)‑4‑phenyl‑4H‑
zol‑3‑yl)thio)propanamide (19) White solid (0.34 g, 69%);
mp = 242–244 °C; IR (KBr) νmax cm−1: 3424 (NH), 3042
(CH aromatic), 2935 (CH aliphatic), 1693 (C=O), 1537
(C=C); 1H NMR (DMSO-d6) δ: 10.11 (brs, 1H, NH), 7.52
(d, J=2.4 Hz, 2H), 7.23–6.84 (m, 11H), 3.41 (t, J=6.3, 2H,
SCH2), 2.84 (t, J =6.6, 2H, CH2CO), 2.27 (s, 3H, CH3);
13C NMR (DMSO-d6) δ: 169.5, (C=O), 154.3, (triazole
C-5), 151.0, (triazole C-3), 144.2, (N-phenyl C-1), 139.4,
(NH-phenyl C-1), 133.8, (phenyl C-4), 132.7, (phenyl C-1),
130.0, (NH-phenyl C-3, C-5), 129.9, (phenyl C-3, C-5),
129.3, (N-phenyl C-3, C-5), 129.1, (N-phenyl C-4), 128.5,
(N-phenyl C-2, C-6), 127.7, (NH-phenyl C-2, C-6), 127.5,
(NH-phenyl C-4), 123.7, (phenyl C-2, C-6), 36.8, (SCH2),
20.8, (CH3); MS (m/z, %): 493 (M+, 3.12%), 495 (M + 2,
2.91%). Anal. Calc. for C24H21BrN4OS (M.W. = 493): C,
58.42; H, 4.29; N, 11.35; Found: C, 58.44; H, 4.32; N,
11.39%.
1,2,4‑triazol‑3‑yl)thio)acetamide (21) White solid (0.36 g,
1
74%); mp = 243–245 °C; H NMR (DMSO-d6) δ: 10.56
(brs, 1H, NH), 7.56–7.48 (m, 5H), 7.41 (d, J=8.4 Hz, 2H),
7.36 (d, J=8.8 Hz, 2H), 7.28 (d, J=8.0 Hz, 2H), 6.90 (d,
J=8.4 Hz, 2H), 4.16 (s, 2H, SCH2), 3.72 (s, 3H, OCH3); 13
C
NMR (DMSO-d6) δ: 164.9, (C=O), 155.3, (triazole C-5),
151.6, (triazole C-3), 133.7, (N-phenyl C-1), 131.9, (NH-
phenyl C-1), 130.0, (phenyl C-3, C-5), 129.9, (N-phenyl C-3,
C-5), 128.5, (phenyl C-1, C-4), 127.8, (N-phenyl C-2, C-6),
127.6, (NH-phenyl C-2, C-6), 126.5, (N-phenyl C-4),120.6,
(phenyl C-2, C-6), 113.9, (NH-phenyl C-4), 55.1, (OCH3),
36.8, (SCH2); MS (m/z, %): 494 (M+, 0.8%). Anal. Calc. for
C23H19BrN4O2S (M.W.=494): C, 55.76; H, 3.87; N, 11.31;
Found: C, 55.88; H, 3.89; N, 11.36%.
N‑(4‑Chlorophenyl)‑2‑((5‑(4‑methoxyphenyl)‑4‑phenyl‑4H‑1,2,
N‑(4‑Methoxyphenyl)‑3‑((4‑phenyl‑5‑(p‑tolyl)‑4H‑1,2,4‑tria-
4‑triazol‑3‑yl)thio)acetamide (22) White solid (0.36 g, 80%);
mp=239–241 °C; 1H NMR (DMSO-d6) δ: 10.50 (brs, 1H,
NH), 7.61–7.54 (m, 5H), 7.42 (d, J=8.4 Hz, 2H), 7.38 (d,
J=8.8 Hz, 2H), 7.28 (d, J=8.8 Hz, 2H), 6.90 (d, J=8.8 Hz,
2H), 4.16 (s, 2H, SCH2), 3.72 (s, 3H, OCH3); 13C NMR
(DMSO-d6) δ: 165.6, (C=O), 153.4, (triazole C-5), 161.0,
(phenyl C-4), 151.8, (triazole C-3), 137.7, (N-phenyl C-1),
134.6, (NH-phenyl C-1), 133.4, (phenyl C-3, C-5), 130.2,
(N-phenyl C-3, C-5), 130.0, (N-phenyl C-4 & phenyl C-1),
129.6, (N-phenyl C-2, C-6), 128.7, (NH-phenyl C-2, C-6),
127.5, (N-phenyl C-4),127.0, (phenyl C-2, C-6), 125.3,
(NH-phenyl C-4), 56.1, (OCH3), 36.7, (SCH2); MS (m/z,
%): 452 (M+2, 0.98%), 452 (M+, 157%). Anal. Calc. for
C23H19ClN4O2S (M.W.=450): C, 61.26; H, 4.25; N, 12.42;
Found: C, 61.29; H, 4.27; N, 12.48%.
zol‑3‑yl)thio)propanamide (20) White solid (0.29 g, 66%);
mp = 226–228 °C; IR (KBr) νmax cm−1: 3431 (NH), 3059
(CH aromatic), 2945 (CH aliphatic), 1680 (C=O), 1515
(C=C); 1H NMR (DMSO-d6) δ: 9.83 (brs, 1H, NH), 7.52 (d,
J=8.1 Hz, 2H), 7.22 (d, J=8.1 Hz, 2H), 7.14 (d, J=8.1 Hz,
2H), 7.10–6.84 (m, 7H), 3.39 (t, J =6.9, 2H, SCH2), 2.79
(t, J =6.9, 2H, CH2CO), 3.71 (s, 3H, OCH3); 13C NMR
(DMSO-d6) δ: 169.4, (C=O), 154.2, (triazole C-5), 151.0,
(triazole C-3), 144.1, (N-phenyl C-1), 139.3, (NH-phenyl
C-1), 133.7, (phenyl C-4), 132.7, (phenyl C-1), 130.1, (NH-
phenyl C-3, C-5), 129.8, (phenyl C-3, C-5), 129.3, (N-phenyl
C-3, C-5), 129.0, (N-phenyl C-4), 128.4, (N-phenyl C-2,
C-6), 127.7, (NH-phenyl C-2, C-6), 127.4, (NH-phenyl C-4),
1 3

Molecular Diversity
2‑((5‑(4‑Methoxyphenyl)‑4‑phenyl‑4H‑1,2,4‑triazol‑3‑yl)
2‑((5‑(4‑Methoxyphenyl)‑4‑phenyl‑4H‑1,2,4‑triazol‑3‑yl)
thio)‑N‑(p‑tolyl)acetamide (23) White solid (0.30 g, 70%);
mp = 219–221 °C; IR (KBr) νmax cm−1: 3431 (NH), 3081
(CH aromatic), 2964 (CH aliphatic), 1680 (C=O), 1523
(C=C); 1H NMR (DMSO-d6) δ: 10.26 (brs, 1H, NH), 7.55–
7.42 (m, 7H), 7.29 (d, J=8.0 Hz, 2H), 7.12 (d, J=7.6 Hz,
2H), 6.90 (d, J=8.0 Hz, 2H), 4.16 (s, 2H, SCH2), 3.72 (s,
3H, OCH3), 2.24 (s, 3H, CH3); 13C NMR (DMSO-d6) δ:
165.6, (C=O), 153.5, (triazole C-5), 151.8, (phenyl C-1),
137.7, (triazole C-3), 134.6, (N-phenyl C-1), 133.5, (NH-
phenyl C-1), 130.3, (phenyl C-3, C-5), 130.1, (N-phenyl
C-3, C-5), 129.6, (phenyl C-4), 128.8, (N-phenyl C-2, C-6),
127.6, (NH-phenyl C-2, C-6), 127.0, (N-phenyl C-4), 125.3,
(phenyl C-2, C-6), 120.6, (NH-phenyl C-4), 56.3, (OCH3),
36.7, (SCH2), 20.6, (CH3); MS (m/z, %): 430 (M+, 10.81%).
Anal. Calc. for C24H22N4O2S (M.W. = 430): C, 66.96; H,
5.15; N, 13.01; Found: C, 67.06; H, 5.18; N, 13.07%.
thio)‑N‑(naphthalen‑1‑yl)acetamide (25) White solid
(0.32 g, 70%); mp=227–229 °C; 1H NMR (DMSO-d6) δ:
10.34 (brs, 1H, NH), 7.56–7.49 (m, 8H), 7.42 (d, J=8.4 Hz,
4H), 7.28 (d, J=8.8 Hz, 2H), 6.90 (d, J=9.2 Hz, 2H), 4.17
(s, 2H, SCH2), 3.82, (s, 3H, OCH3); 13C NMR (DMSO-
d6) δ: 167.1, (C=O), 158.3, (phenyl C-4), 144.8, (triazole
C-5), 142.3, (triazole C-3), 139.3, (N-phenyl C-1), 138.8,
(N-phenyl C-1), 134.1, (naphthyl C-4a), 132.2, (phenyl
C-4), 130.0, (phenyl C-3, C-5), 129.3, (N-phenyl C-3, C-5),
128.3, (N-phenyl C-6), 127.5, (naphthyl C-3), 124.1, (phe-
nyl C-2, C-6), 123.6, (N-phenyl C-2, C-6), 120.5, (naphthyl
C-7), 120.3, (naphthyl C-8), 118.5, (naphthyl C-8a), 117.6,
(naphthyl C-4), 114.5, (naphthyl C-2), 56.1, (OCH3), 42.3,
(SCH2); MS (m/z, %): 466 (M+, 8.09%). Anal. Calc. for
C27H22N4O2S (M.W. = 466): C, 69.51; H, 4.75; N, 12.01;
Found: C, 69.58; H, 4.77; N, 12.10%.
N‑(4‑Methoxyphenyl)‑2‑((5‑(4‑methoxyphenyl)‑4‑phenyl‑4H
2‑((5‑(4‑Methoxyphenyl)‑4‑phenyl‑4H‑1,2,4‑triazol‑3‑yl)
‑1,2,4‑triazol‑3‑yl)thio)acetamide (24) White solid (0.28 g,
65%); mp=226–228 °C; IR (KBr) νmax cm−1: 3460 (NH),
3073 (CH aromatic), 2952 (CH aliphatic), 1681 (C=O),
thio)‑N‑(pyridin‑2‑yl)acetamide (26) White solid (0.29 g,
70%); mp=252–254 °C; IR (KBr) νmax cm−1: 3428 (NH),
3027 (CH aromatic), 2872 (CH aliphatic), 1665 (C=O), 1536
(C=C); 1H NMR (DMSO-d6) δ: 10.49 (brs, 1H, NH), 7.58
(d, J=8.8 Hz, 2H), 7.53 (d, J=7.6 1H), 7.51 (d, J=7.2, 1H),
7.42 (t, J=7.2, 1H), 7.28 (t, J=7.2, 1H), 7.23 (t, J=7.2 Hz,
2H), 7.21 (d, J=7.2 Hz, 2H), 7.15 (d, J=7.6 Hz, 2H), 7.11
1
1542 (C=C); H NMR (DMSO-d6) δ: 10.21 (brs, 1H,
NH), 7.56–7.42 (m, 7H), 7.28 (d, J=8.0 Hz, 2H), 6.90 (d,
J = 8.4 Hz, 4H), 4.13 (s, 2H, SCH2), 3.72 (s, 3H, OCH3),
3.71 (s, 3H, OCH3); 13C NMR (DMSO-d6) δ: 169.8, (C=O),
158.8, (phenyl C-4) 144.8, (NH-phenyl C-4), 139.3, (triazole
C-5), 138.9, (triazole C-3), 136.0, (N-phenyl C-1), 134.3,
(NH-phenyl C-1), 132.2, (phenyl C-3, C-5), 130.1, (N-phenyl
C-3, C-5), 128.9, (phenyl C-4), 127.5, (N-phenyl C-2, C-6),
123.9, (NH-phenyl C-2, C-6), 123.5, (N-phenyl C-4), 120.5,
(phenyl C-2, C-6), 117.5, (NH-phenyl C-4), 55.4, (OCH3),
55.1, (OCH3), 37.1, (SCH2); MS (m/z, %): 446 (M+, 1.60%).
Anal. Calc. for C24H22N4O3S (M.W. = 446): C, 64.56; H,
4.97; N, 12.55; Found: C, 64.60; H, 5.01; N, 12.59%.
(t, J=9.2, 1H), 4.20 (s, 2H, SCH2), 3.72 (s, 3H, OCH3); 13
C
NMR (DMSO-d6) δ: 168.8, (C=O), 144.8, (triazole C-5),
139.2, (Pyridyl C-2), 138.9, (triazole C-3), 134.9, (Pyridyl
C-6), 134.8, (N-phenyl C-1), 134.4, (Pyridyl C-4), 132.1,
(phenyl C-1), 129.6, (phenyl C-4), 129.2, (phenyl C-3, C-5),
127.6, (N-phenyl C-3, C-5), 124.4, (N-phenyl C-4), 123.0,
(N-phenyl C-2, C-6), 120.5, (phenyl C-2, C-6), 120.2, (Pyri-
dyl C-5), 117.4, (Pyridyl C-3), 55.7, (OCH3), 37.7, (SCH2);
Anal. Calc. for C22H19N5O2S (M.W. = 417): C, 63.29; H,
4.59; N, 16.78; Found: C, 63.38; H, 4.61; N, 16.80%.
1 3

Molecular Diversity
N ‑ ( 5 ‑ C h l o r o p y r i d i n ‑ 2 ‑ y l ) ‑ 2 ‑ ( ( 5 ‑ ( 4 ‑ m e t h -
oxyphenyl)‑4‑phenyl‑4H‑1,2,4‑triazol‑3‑yl)thio)acetamide
N‑(4‑Methoxyphenyl)‑3‑((5‑(4‑methoxyphenyl)‑4‑phenyl‑
4H‑1,2,4‑triazol‑3‑yl)thio)propanamide (29) White solid
(0.27 g, 60%); mp = 227–229 °C; IR (KBr) νmax cm−1
:
(27) White solid (0.34 g, 75%); mp = 242–244 °C; IR
(KBr) νmax cm−1: 3423 (NH), 3071 (CH aromatic), 2968
(CH aliphatic), 1673 (C=O); 1H NMR (DMSO-d6) δ: 10.19
(brs, 1H, NH), 7.58 (d, J=4.2 Hz, 2H), 7.56 (d, J=3.6 1H),
7.54 (d, J=3.6, 1H), 7.46 (t, J=6.3, 1H), 7.43 (t, J=3.0 Hz,
2H), 7.40 (d, J=3.6 Hz, 2H), 7.34 (d, J=1.9 Hz, 2H), 6.90
3431 (NH), 3059 (CH aromatic), 2945 (CH aliphatic), 1680
(C=O), 1515 (C=C); 1H NMR (DMSO-d6) δ: 9.83 (brs, 1H,
NH), 739–7.52 (m, 9H), 7.28 (d, J=6.9 Hz, 2H), 6.90 (d,
J = 9.0 Hz, 2H), 3.72 (s, 3H, OCH3), 3.70 (s, 3H, OCH3),
3.71 (t, J = 6.9, 2H, SCH2), 2.79 (t, J =6.9, 2H, CH2CO);
13C NMR (DMSO-d6) δ: 170.0, (C=O), 154.3, (triazole
C-5), 151.1, (triazole C-3), 144.2, (N-phenyl C-1), 139.5,
(NH-phenyl C-1), 133.8, (phenyl C-4), 132.8, (phenyl C-1),
130.1, (NH-phenyl C-3, C-5), 129.8, (phenyl C-3, C-5),
129.1, (N-phenyl C-3, C-5), 129.0, (N-phenyl C-4), 128.3,
(N-phenyl C-2, C-6), 127.6, (NH-phenyl C-2, C-6), 127.5,
(NH-phenyl C-4), 123.6, (phenyl C-2, C-6), 56.2, (2OCH3),
33.1, (SCH2), 29.4, (CH2); MS (m/z, %): 460 (M+, 1.39%).
Anal. Calc. for C25H24N4O3S (M.W. = 460): C, 65.20; H,
5.25; N, 12.17; Found: C, 65.27; H, 5.28; N, 12.24%.
(t, J=9.0, 1H), 4.16 (s, 2H, SCH2), 3.72 (s, 3H, OCH3); 13
C
NMR (DMSO-d6) δ: 168.6, (C=O), 144.8, (triazole C-5),
139.3, (Pyridyl C-2), 138.9, (triazole C-3), 134.8, (Pyridyl
C-6), 134.8, (N-phenyl C-1), 134.4, (Pyridyl C-4), 132.4,
(phenyl C-1), 129.6, (phenyl C-4), 129.1, (phenyl C-3, C-5),
127.4, (N-phenyl C-3, C-5), 124.0, (N-phenyl C-4), 123.8,
(N-phenyl C-2, C-6), 120.5, (phenyl C-2, C-6), 120.1, (Pyri-
dyl C-5), 117.3, (Pyridyl C-3), 58.7, (OCH3), 37.8, (SCH2).
Anal. Calc. for C22H18ClN5O2S (M.W.=435): C, 58.47; H,
4.01; N, 15.50; Found: C, 58.51; H, 4.04; N, 15.57%.
N‑(4‑Bromophenyl)‑3‑((5‑(4‑methoxyphenyl)‑4‑phenyl‑4H‑1,
Biological evaluation
In vitro cytotoxic activity
The antitumor activity of new triazoles against MDA-
MB-231 cells was evaluated by using the tetrazolium salt
3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium
bromide (MTT) assay in accordance with a reported method
[50].
2,4‑triazol‑3‑yl)thio)propanamide (28) White solid (0.34 g,
67%); mp=246–248 °C; IR (KBr) νmax cm−1: 3426 (NH),
3062 (CH aromatic), 2920 (CH aliphatic), 1676 (C=O),
1
1542 (C=C); H NMR (DMSO-d6) δ: 10.11 (brs, 1H,
NH), 7.55–7.35 (m, 9H), 7.27 (d, J=2.1 Hz, 2H), 6.90 (d,
J = 8.7 Hz, 2H), 3.73 (s, 3H, OCH3), 3.37 (t, J =6.9, 2H,
SCH2), 2.84 (s, 2H, CH2CO); 13C NMR (DMSO-d6) δ:
169.5, (C=O), 154.32, (triazole C-5), 151.0, (triazole C-3),
144.2, (N-phenyl C-1), 139.4, (NH-phenyl C-1), 133.8, (phe-
nyl C-4), 132.7, (phenyl C-1), 130.0, (NH-phenyl C-3, C-5),
129.9, (phenyl C-3, C-5), 129.3, (N-phenyl C-3, C-5), 129.1,
(N-phenyl C-4), 128.5, (N-phenyl C-2, C-6), 127.7, (NH-
phenyl C-2, C-6), 127.5, (NH-phenyl C-4), 123.6, (phenyl
C-2, C-6), 56.1, (OCH3), 33.2, (SCH2), 29.4, (CH2); MS
(m/z, %): 509 (M+, 2.83%), 511 (M+2, 2.62%). Anal. Calc.
for C24H21BrN4O2S (M.W. = 509): C, 56.59; H, 4.16; N,
11.00; Found: C, 56.71; H, 4.22; N, 11.09%.
In silico cytotoxicity and ADMET profles
In silico CLC-prediction system [43] and pkCSM descrip-
tors algorithm protocol [47] were used to predict the cyto-
toxicity and to study ADMET profles of new triazoles.
Docking studies
In the present study, all docking experiments were per-
formed for all the fnal target hybrid structures using Molec-
ular Operating Environment software (MOE2014, https://
www.chemcomp.com/Products.htm) to evaluate the binding
free energy and to explore the binding mode toward STAT3
1 3

Molecular Diversity
6. Hong DS, Angelo LS, Kurzrock R (2007) Interleukin-6 and
its receptor in cancer. Cancer 110:1911–1928. https://doi.
org/10.1002/cncr.22999
(PDB: 6NJS, Resolution: 2.70 Å, https://www.rcsb.org/struc
ture/6NJS) and considered as a target for docking simulation
[45]. Firstly, the crystal structure of the protein was pre-
pared by removing water molecules and retaining the essen-
tial chain and the co-crystallized ligand. After that, protein
protonated, the energy minimized, and the binding pocket
of the protein defned. The 3D structures of new triazoles
were sketched using Chem3D 15.0, energy minimized, and
fnally saved in molfle format. Molecular docking of fnal
target compounds was performed by the default protocol
against the target receptor. In each case, 10 docked poses
were generated using genetic algorithm searches, and Afn-
ity dG & London dG were used for scoring 1 and Scoring 2,
respectively. The London dG scoring function predicts the
free energy of binding of the ligand from a given pose. The
functional form is a sum of terms:
7. Lee H, Deng J, Kujawski M et al (2010) STAT3-induced S1PR1
expression is crucial for persistent STAT3 activation in tumors.
Nat Med 16:1421–1428. https://doi.org/10.1038/nm.2250
8. Sgrignani J, Garofalo M, Matkovic M et al (2018) Structural
biology of STAT3 and its implications for anticancer therapies
development. Int J Mol Sci 19:1591. https://doi.org/10.3390/
ijms19061591
9. Chen H, Guan Y, Yuan G et al (2014) A perylene derivative reg-
ulates HIF-1α and Stat3 signaling pathways. Bioorg Med Chem
22:1496–1505. https://doi.org/10.1016/j.bmc.2013.10.018
10. Robinson AJ, Kunji ERS, Gross A (2012) Mitochondrial car-
rier homolog 2 (MTCH2): the recruitment and evolution of a
mitochondrial carrier protein to a critical player in apoptosis.
Exp Cell Res 318:1316–1323. https://doi.org/10.1016/j.yexcr
.2012.01.026
11. Lee JH, Kim JE, Kim BG et al (2016) STAT3-induced WDR1
overexpression promotes breast cancer cell migration. Cell Signal
28:1753–1760. https://doi.org/10.1016/j.cellsig.2016.08.006
12. Sánchez-Ceja SG, Reyes-Maldonado E, Vázquez-Manríquez ME
et al (2006) Diferential expression of STAT5 and Bcl-xL, and
high expression of Neu and STAT3 in non-small-cell lung carci-
noma. Lung Cancer 54:163–168. https://doi.org/10.1016/j.lungc
an.2006.07.012
ꢀ
ꢀ
ꢀ
ΔG = C + Eflex
+
CHBFHB
+
CMFM
+
ΔDi
h-bond
m-lig
atom i
where C is the average gain or loss of rotational and transla-
tional entropy; Efex represents the energy upon loss of fex-
ibility of the ligand; CHB and FHB are the energy of an ideal
hydrogen bond and the geometric imperfections of hydrogen
bonds, respectively; CM and FM represent the energy of an
ideal metal ligation and the measure of geometric imperfec-
tions of metal ligations, respectively; Di is the dissolvation
energy of an atom i.
13. Ke Y, Bao T, Wu X et al (2017) Scutellarin suppresses migration
and invasion of human hepatocellular carcinoma by inhibiting
the STAT3/Girdin/Akt activity. Biochem Biophys Res Commun
483:509–515. https://doi.org/10.1016/j.bbrc.2016.12.114
14. Mahanti S, Sunkara S, Bhavani R (2019) Synthesis, biological
evaluation and computational studies of fused acridine containing
1,2,4-triazole derivatives as anticancer agents. Synth Commun
49:1729–1740. https://doi.org/10.1080/00397911.2019.1608450
15. Mioc M, Avram S, Bercean V et al (2018) Design, synthesis
and biological activity evaluation of S-substituted 1H-5-Mer-
capto-1,2,4-triazole derivatives as antiproliferative agents in
colorectal cancer. Front Chem. https://doi.org/10.3389/fchem
.2018.00373
Compliance with ethical standards
Conflict of interest The authors declare that they have no confict of
16. Ghanaat J, Khalilzadeh MA, Zareyee D (2020) Molecular
docking studies, biological evaluation and synthesis of novel
3-mercapto-1,2,4-triazole derivatives. Mol Divers. https://doi.
org/10.1007/s11030-020-10050-0
interest.
17. Tariq S, Kamboj P, Alam O, Amir M (2018) 1,2,4-Triazole-based
benzothiazole/benzoxazole derivatives: design, synthesis, p38α
MAP kinase inhibition, anti-infammatory activity and molec-
ular docking studies. Bioorg Chem 81:630–641. https://doi.
org/10.1016/j.bioorg.2018.09.015
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