Design, synthesis, antimicrobial evaluation and docking studies of urea-triazole-amide hybrids

Article abstract of DOI:10.1016/j.molstruc.2020.128234

A series of urea-1,2,3-triazole-amide hybrids was designed and synthesized via click reaction of urea derivatives containing a propargyl unit with 2-bromo-N-phenylacetamide derivatives and characterized by FTIR, NMR and HRMS data. The antimicrobial evalua

Full text of DOI:10.1016/j.molstruc.2020.128234

Journal Pre-proof
Design, synthesis, antimicrobial evaluation and docking studies of urea-triazole-amide
hybrids
Kashmiri Lal, Nisha Poonia, Poonam Rani, Ashwani Kumar, Anil Kumar
PII:
S0022-2860(20)30559-7
DOI:
https://doi.org/10.1016/j.molstruc.2020.128234
MOLSTR 128234
Reference:
To appear in: Journal of Molecular Structure
Received Date: 10 February 2020
Revised Date: 7 April 2020
Accepted Date: 9 April 2020
Please cite this article as: K. Lal, N. Poonia, P. Rani, A. Kumar, A. Kumar, Design, synthesis,
antimicrobial evaluation and docking studies of urea-triazole-amide hybrids, Journal of Molecular
Structure (2020), doi: https://doi.org/10.1016/j.molstruc.2020.128234.
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Credit author statement
Kashmiri Lal: Conceptualization, Methodology, Resources, Data curation, Supervision. Nisha
Poonia: Validation, Formal analysis, Investigation Writing - original draft, Writing -
review. Poonam
Rani:
Methodology,
Data
curation,
Visualization,
Ashwani
Kumar: Software, Data curation. Anil Kumar: Formal analysis, Investigation.

Design, Synthesis, Antimicrobial Evaluation and Docking Studies of Urea-Triazole-
Amide Hybrids
Kashmiri Lal,1,* Nisha Poonia,1 Poonam Rani,1 Ashwani Kumar,2 and Anil Kumar3
1Department of Chemistry, Guru Jambheshwar University of Science & Technology, Hisar,
Haryana 125001, India
2Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science &
Technology, Hisar, Haryana 125001, India
3Department of Bio and Nanotechnology, Guru Jambheshwar University of Science &
Technology, Hisar, Haryana 125001, India
*Corresponding author: klal_iitd@yahoo.com (Kashmiri Lal)
Abstract
A series of urea-1,2,3-triazole-amide hybrids was designed and synthesized via click
reaction of urea derivatives containing a propargyl unit with 2-bromo-N-phenylacetamide
derivatives and characterized by FTIR, NMR and HRMS data. The antimicrobial evaluation
of these synthesized compounds towards three bacteria (Bacillus subtilis, Escherichia coli and
Staphylococcus aureus) and two fungi (Aspergillus niger and Candida albicans) was carried
out. The activity results revealed that all these hybrids 4(a-r) exhibited better activity than
their precursors i.e. alkynes 2(a-c). Moreover, almost all the synthesized triazoles were found
to be more potent than the reference drug Fluconazole against C. albicans. Further, docking
studies of compound 4j in the active sites of S. aureus DNA gyrase complexed with DNA and
antifungal target Lanosterol 14-α demethylase were also carried out.
Keywords: Urea, 1,2,3-Triazole, amide, antimicrobial activity, docking studies
1. Introduction
Multidrug resistance shown by various microorganisms to a variety of antimicrobial
drugs is the major threat globally [1]. The different strains of bacteria, fungi, parasites, etc.
have been proved to be threatening for public health because of enhanced multidrug
resistance. The most common multidrug resistant bacteria are Staphylococcus aureus,
Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumanni, etc [2]. There are many
microorganisms which have been lived for years by their capability to bind with antimicrobial

agents via DNA transfer, etc [3]. But some bacteria or fungi oppose the mechanism of action
of certain antimicrobial drugs rendering them ineffective. Also, there are fungi like Candida
albicans which can attain the decreased cell wall permeability for antifungals leading the drug
to be less effective and hence are multidrug resistant [4-5]. Therefore, there is an emergent
need for the synthesis of some new drugs with a unique mechanism of action and better
binding capabilities. In this regard, molecular hybridization approach for the synthesis of a
single hybrid molecule by the combination of two or more bioactive scaffolds has attracted
considerable attention [6]. The hybrid molecule is supposed to be more active than its parent
fragments. Recently, a large number of hybrids from different biologically active scaffolds
such as 1,2,3-triazole, pyrazole, imidazole, dihydropyridine, Mannich base, quinozolinone,
etc. have been evaluated for their antimicrobial potential [7-15].
Click chemistry novice by Sharpless is an important methodology which has gained
tremendous attention because of its use in the synthesis of a wide range of 1,2,3-triazole based
pharmaceutically important molecules [16]. 1,2,3-Triazoles have been explored widely
because of their numerous applications in biochemistry, medicinal chemistry and ion
recognition [17]. 1,2,3-Triazoles have emerged as incredibly important pharmacophores
possessing a wide range of biological activities including anticancer [18-20], antitubercular
[21-22], antimalarial [23-24], antidiabetic [25-26], anti-oxidant [27], anticonvulsant [28],
antimicrobial [29-34], etc. Fluorine atom is an important element which enhances the
chemical stability and metabolic stability of organic compounds [35]. Also, fluorinated
organic compounds are known to exhibit significant biological activity due to the electron
withdrawing effect of fluorine atom which may lead to the enhanced binding affinity of the
compound to a target protein [36].
A large number of urea derivatives have been explored widely by medicinal chemists
because of their ability to exhibit good drug-target interactions mainly via hydrogen bonding
[37]. Organic molecules containing a urea linkage are reported to exhibit plethora of
biological activities like anticancer [38-39], antidiabetic [40-41], antimicrobial [42], etc.
Combining this functionality with other pharmacophoric molecules can lead to a new hybrid
molecule with synergistic improvement in the biological activity. For instance, some
piperazines containing a urea linkage have been reported as potential antibacterial and
antifungal agents [43]. The antimicrobial screening of these piperazines showed that the urea
linkage is responsible for the high activity particularly against E. Coli becterium. Further,
some more urea derivatives exhibiting a very good antimicrobial action against fungus
Cryptococcus neoformans are also reported [44].

Similarly, compounds involving amide linkage are supposed to show better bioactivity
because of their hydrogen bonding capabilities, etc. [45]. Commercially, there are many
antibiotics i.e. ampicillin, diazepam, etc. bearing a amide unit [46]. So, utilizing this amide
unit in drug designing can further enhance the bioactivity of parent compound. Some fluoro
1,2,3-triazoles bearing the amide functionality as good antimicrobial agents are reported [47].
Some antimicrobials with the amide group on benzene ring displayed better antibacterial and
antifungal activity than those with a thiazole ring [48]. Further, compounds bearing 1,2,3-
triazole (Fig. 1) are found to exhibit very good therapeutic effects including marketed drugs
rufinamide, cefatrizine, etc [33].
Fig. 1. Structures of some biologically active 1,2,3-triazole-amide hybrids
Therefore, based upon aforementioned and our target towards the development of
triazole based drug molecules, some hybrids by combining three pharmacophoric units
including urea, amide and 1,2,3-triazole were designed (Fig. 2). Herein, we report the
synthesis of some urea-1,2,3-triazole-amide hybrids as potential antimicrobial agents.

Fig. 2. Designing of urea-1,2,3-triazole-amide hybrids.
2. Results and discussion
2.1.Chemistry
The synthesis of urea-linked 1,2,3-triazoles was carried out in three steps as depicted in
Scheme 1. Firstly, commercially available substituted phenyl isocyanates 1(a-c) were reacted
with propargyl amine using triethylamine in dry dichloromethane (DCM) to yield the desired
terminal alkynes 2(a-c) in good yield [49]. The IR spectrum of urea-linked alkyne 2a
exhibited two characteristic bands at 3298 cm-1 and 2100 cm-1 due to alkyne C-H and C-C
stretching, respectively. A strong band was observed at 1680 cm-1 due to C=O stretching. The
1H NMR spectrum of compound 2a exhibited a doublet of doublet at δ 3.88 (J = 5.7 Hz, 2.4
Hz) and a triplet at δ 3.10 (J = 2.3 Hz) confirming the terminal alkyne formation. The other
precursors for triazole synthesis i.e. 2-bromo-N-phenylacetamides 3(a-f) were prepared by the
reaction of aniline derivatives with bromoacetyl bromide in the presence of K2CO3 in DCM
[50]. Then, urea derivatives with alkyne group 2(a-c) were subjected to click reaction with
various in situ generated organic azides from 2-bromo-N-phenylacetamides 3(a-f) and sodium
azide in presence of copper sulphate and sodium ascorbate to provide urea-1,23-triazole-
amide hybrids 4(a-r) in good yield. A plausible mechanism for the synthesis of urea-1,23-
triazole-amide hybrids 4(a-r) is mentioned in the scheme 2 [51].

Scheme 1: Reagents and conditions: (i) Propargyl amine, Et3N, Dichloromethane, 0 °C; 1
h
(ii) Sodium azide; CuSO4.5H2O, sodium ascorbate, DMF:water (1:1); 40 °C; 2-3
h.
Table 1: Synthesis of urea-1,2,3-triazole-amide hybrids 4(a-r)
Sr.
No.
1
2
3
4
5
6
7
8
9
10
11
12
Compound R1
R2
Yield
(%)
60
85
88
70
52
82
88
89
86
84
83
S.no. Compound R1
R2
Yield
(%)
87
83
90
-
-
-
-
-
-
2-F
3-F
4-F
2-CF3
3-CF3
4-CF3
2-F
3-F
4-F
13
14
15
16
17
18
19
20
21
22
23
24
Cl
Cl
Cl
Cl
Cl
Cl
2-F
3-F
4-F
2-CF3 81
3-CF3 79
4-CF3 86
3a
3b
3c
3d
3e
3f
4g
4h
4i
4j
4k
4l
4m
4n
4o
4p
4q
4r
F
OMe 2-F
OMe 3-F
OMe 4-F
OMe 2-CF3 81
OMe 3-CF3 88
OMe 4-CF3 85
89
78
87
4a
4b
4c
4d
4e
4f
F
F
F
F
F
2-CF3
3-CF3
4-CF3
86

O
O
Br
N
HN
HN
N+
NaN3
N-
R2
R2
3
O
O
HN
N
HN
N
H
Cu
H
Cu
N
O
N+
NH
N
R1
A
R1
R2
Cu+
O
HN
N
H
O
H2O
R2
HN
N
Cu
O
HN
R1
H
N
N
O
N
NH
2
R2
N
N
HN
R2
B
R1
O
N
Cu
N
N
NH
N
O
HN
NH
O
HN
R1
C
R1
4
Scheme 2: Proposed mechanism for the synthesis of urea-1,23-triazole-amide hybrids 4(a-r).
The characterization of all the triazole hybrids was done using FTIR, 1H NMR, 13C NMR and
HRMS spectral techniques (Fig. 3).
FTIR analysis

The IR spectrum of 4l showed a characteristic band at 3136 cm-1 which confirms the formation
of triazole ring. Two bands observed at 1668 cm-1 and 1662 cm-1 were assigned to two C=O
stretching bands of amide and urea carbonyl groups, respectively.
1H NMR analysis
1
In the H NMR spectrum of 4l, a characteristic singlet due to triazolyl proton at δ 8.01
confirmed the formation of triazole ring. A sharp singlet due to methylene protons attached to
amide group was obtained at δ 5.37, while methylene protons linked with urea unit appeared
as a doublet at δ 4.38 (J = 5.6 Hz). One of the –NH- of urea moiety appeared as a triplet at δ
6.68 (J = 5.6 Hz) while, other –NH- was observed at δ 8.74. The NH of amide functionality
appeared as a singlet signal at δ 10.80.
13C NMR analysis
13
The C NMR spectrum of the compound 4l was clearly analyzed and the values were
13
assigned to different carbon atoms using HMBC, HSQC, COSY, DEPT-135,19F NMR, C
NMR techniques (Fig. 3). Out of the two carbonyl carbons, one (urea) appeared at δ 155.43
and the other carbon (amide) appeared at δ 165.48. HSQC analysis revealed that the carbon
atom next to urea linkage appeared at δ 35.32 and carbon attached to amide linkage was
observed at δ 52.65. HSQC also helped in predicting the signal of carbon atom C-5 bearing
the triazolyl proton at δ 124.86. A quartet appeared at δ 126.71 (J = 3 Hz) in 13C NMR spectra
was assigned to carbon atoms of the benzene ring ortho to trifluoromethyl group.
19F NMR analysis
19
A singlet was observed at δ – 60.42 in F NMR spectrum of compound 4l signal due to
trifluoromethyl group at benzene ring.
HRMS analysis
Compound 4l displayed a signal at m/z 453.1307 corresponding to [M + H]+ which is in
agreement to the calculated value. All the other synthesized compounds showed the similar
analytical and spectral pattern.

Fig. 3: Characteristic chemical shift values (δ ppm) in 13C NMR and 1H NMR spectra of 4l
2.2. Antimicrobial activity
The antimicrobial evaluation of all the synthesized compounds 2(a-c) and 4(a-r) was carried
out using standard serial dilution method against two Gram (+) bacteria (Staphylococcus
aurius and Bacillus subtilis MTCC 441), one Gram (-) bacterium (Escherichia coli MTCC
16521) as well as two fungi (Aspergillus niger MTCC 8189 and Candida albicans MTCC
227) [ ]. Ciprofloxacin and Fluconazole were taken as standard drugs for antibacterial and
antifungal activity, respectively. The minimum inhibitory concentration values (MIC in
µmol/mL) of the synthesized compounds along with those of the standard drugs are
mentioned in Table 2.
Table 2: Antimicrobial evaluation data of synthesized compounds 2(a-c) and 4(a-r) (MIC in
µmol/mL)
S. No.
1
E. coli
0.1301
0.1198
0.1224
0.0324
0.0324
0.0162
0.0287
0.0287
0.0287
0.0320
0.0320
0.0320
0.0276
0.0276
B. subtilis S. aureus
A. niger
0.1301
0.1198
0.1224
0.0648
0.0324
0.0648
0.0573
0.0573
0.0573
0.0622
0.0622
0.0622
0.0553
0.0553
C.
albicans
0.1301
Compounds
0.1301
0.1198
0.1224
0.0648
0.0648
0.0648
0.0573
0.0573
0.0573
0.0622
0.0311
0.0311
0.0277
0.0553
0.1301
0.1198
0.1224
0.0648
0.0648
0.0648
0.0573
0.0287
0.0287
0.0311
0.0311
0.0311
0.0277
0.0277
2a
2b
2c
4a
4b
4c
4d
4e
4f
2
0.1198
0.1224
0.0324
0.0162
0.0647
0.0287
0.0143
0.0143
0.0311
0.0311
0.0622
0.0138
0.0277
3
4
5
6
7
8
9
10
11
12
13
14
4g
4h
4i
4j
4k

15
16
17
18
19
20
21
22
23
0.0276
0.0628
0.0314
0.0628
0.0279
0.0279
0.0279
0.0553
0.0628
0.0628
0.0628
0.0279
0.0558
0.0558
0.0094
-
0.0277
0.0314
0.0314
0.0314
0.0558
0.0558
0.0279
0.0094
-
0.0138
0.0314
0.0628
0.0628
0.0558
0.0558
0.0558
-
0.0277
0.0314
0.0314
0.0314
0.0279
0.0279
0.0279
-
4l
4m
4n
4o
4p
4q
4r
Ciprofloxacin 0.0094
Fluconazole
-
0.0408
0.0408
The results from antibacterial screening indicated that some of the synthesized
compounds showed significant activity against the tested bacterial strains. Compounds 4f and
4j showed better activity than other tested compounds against E. coli with MIC values of
0.0287 µmol/mL and 0.0276 µmol/mL, respectively. Compounds 4j and 4p displayed good
activity against B. subtilis with MIC values of 0.0277 µmol/mL and 0.0279 µmol/mL,
respectively. Compound 4r with methoxy and trifluoromethyl substituents on phenyl rings
displayed good activity against E. coli and S. aureus with MIC value of 0.0279 µmol/mL. The
antifungal activity data revealed that compounds 4b (MIC = 0.0324 µmol/mL), 4l (MIC =
0.0138 µmol/mL) and 4m (MIC = 0.0314 µmol/mL) were found to be more potent than the
standard drug Fluconazole (0.0408 µmol/mL). Moreover, most of the hybrids displayed better
activity than the reference drug Fluconazole against C. albicans. Among them 4e (0.0143
µmol/mL) and 4j (0.0138 µmol/mL) exhibited very good potency against C. albicans.
Compound 4j was found to be more active against all the tested bacterial and fungal strains.
2.2.1. Structure activity relationship
All the synthesized 1,2,3-triazole hybrids 4(a-r) were found to show better activity than the
alkynes 2(a-c). This enhanced activity clearly indicates the effect of molecular hybridization
when the three bioactive scaffolds amide, 1,2,3-triazole and urea were linked together. It was
noticed that introducing trifluoromethyl substituent at any position on benzene ring led to
enhanced biological activity against most of the tested microorganisms. Compound 4r

containing methoxy and trifluoromethyl groups at para position of benzene ring displayed
better activity against E. coli and S. aureus. Compounds with trifluoromethyl substituted
benzene displayed better activity than those having fluoro substituent on the benzene ring.
2.3 Docking Studies
Antimicrobial screening revealed that compound 4j exhibited good activity against all the
tested microorganism. To find its binding interactions and conformation, docking studies were
carried out in the active site of S. aureus DNA gyrase complexed with DNA and antifungal
target Lanosterol 14-α demethylase. In DNA gyrase, most favourable conformation of 4j
showed important binding attributes [52]. One fluorine atom of trifluoromethyl group made
hydrogen bond with Ser1084 and carbon hydrogen bond with Gly1082 while another fluorine
atom was involved in halogen bond with Asp1083. Amide group also played important role in
anchoring by hydrogen bonding with Ser1084. Pi electrons of chlorophenyl ring interacted
with Arg458 through pi-cation electrostatic interactions. The molecule 4j also interacted with
DNA fragments. Phosphate group of DT8 and trifluromethyl phenyl ring were involved in pi-
anion interactions. Nitrogen of triazole created a hydrogen bond with DA13. Pi orbitals of
triazole and chlorophenyl ring were interacted with DG9 and DA13 via V-shaped pi-pi
stacked interactions. Ser1084 was involved in hydrogen bonding with carbonyl group of
ciprofloxacin also and further, DG9 and DA13 helped in affixing ciprofloxacin through pi-pi
stacked interactions with fluoroquinolone pi electrons ring centres. These observations clearly
explained good inhibitory activity of compound 4j against S. aureus. The above discussed
interactions are shown in fig. 3a and 3b.
3a

3b
Figure 3: Docked poses of compound 4j (3a) with amino acids and (3b) with phosphate
groups in the active site of S. aureus DNA gyrase complexed with DNA.
In case of Lanosterol 14-α demethylase, fluorine atom made halogen bond and hydrophobic
attachments with heme molecule. Trifluorophenyl ring generated T-shaped pi-pi interaction
with heme molecule. Interactions of heme molecule with azoles have been reported as the
important part of binding of azole drugs. The carbonyl oxygen of urea constructed with NH of
Ser382. Triazole ring built pi-pi stacked interactions with Tyr126 and pi-sulfur bond with
Met509. Chlorophenyl ring produced T-shaped pi-pi interaction with His381 (Fig. 4). These
facts explained the good antifungal activity of compound 4j.
Figure 4: Docked poses of compound 4j in the active site of antifungal target Lanosterol 14-
α demethylase.
2.4. ADME analysis
Molinspiration was used to predict the bioactivity score of the synthesized compounds
(Table 3). The drug likeness of the synthesized compounds was predicted on the basis of their

bioactivity score. None of the compounds 4(a-r) violated Lipinski’s rule-of-five. All the
synthesized compounds has molecular weight ≤500, number of hydrogen bond acceptors ≤10,
number of hydrogen bond donors ≤5, miLog P ≤5. The number of rotatable bonds in
compounds 4(a-r) clearly defines the flexible nature of compounds. The synthesized hybrids
are expected to show good permeability across the cell membrane on the basis of values of
miLog P. Greater total polar surface area (TPSA) values of 4(a-r) than those of 2(a-c) predicts
their better transport properties because of better hydrogen bonding capacity. Percentage
absorption was calculated as % ABS = 109 - (0.345xTPSA) [53]. The synthesized compounds
are predicted to have drug like nature as suggested by Molinspiration calculations.
Table 3: ADME analysis of compounds 2(a-c) and 4(a-r).
Entr Compound %ABS MW
miLog TPSA Natom nO nOHN nrot Volum
y
1
s
2a
P
s
H
3
H
2
b
2
e
94.81 192.1 1.77
41.12 14
171.82
2
94.81 208.6 2.28
91.62 204.2 1.66
74.17 386.3 2.08
74.17 386.3 2.10
74.17 386.3 2.13
74.17 436.3 2.81
74.17 436.3 2.84
74.17 436.3 2.86
74.17 402.8 2.60
74.17 402.8 2.62
74.17 402.0 2.64
74.17 452.8 3.33
74.17 452.8 3.35
74.17 452.8 3.38
70.99 398.4 1.97
70.99 398.4 2.00
70.99 398.4 2.02
70.99 448.4 2.71
41.12 14
50.36 15
100.9 28
100.9 28
100.9 28
100.9 31
100.9 31
100.9 31
100.9 28
100.9 28
100.9 28
100.9 31
100.9 31
100.9 31
110.1 29
110.1 29
110.1 29
110.1 32
3
4
8
8
8
8
8
8
8
8
8
8
8
8
9
9
9
9
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
2
3
6
6
6
7
7
7
6
6
6
7
7
7
7
7
7
8
180.43
192.44
322.56
322.56
322.56
348.92
348.92
348.92
331.16
331.16
331.16
357.53
357.53
357.53
343.17
343.17
343.17
369.54
2b
2c
4a
4b
4c
4d
4e
4f
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
4g
4h
4i
4j
4k
4l
4m
4n
4o
4p

20
21
70.99 448.4 2.73
70.99 448.4 2.75
110.1 32
110.1 32
9
9
3
3
8
8
369.54
369.54
4q
4r
3. Conclusion
In summary, the synthesis of urea-1,2,3-triazole-amide hybrids from urea linked
alkynes utilising the click chemistry is reported. Some of synthesized hybrids found to be
more potent antimicrobial agents than the standard drug fluconazole. Compound 4j exhibited
good bioactivity against almost all the tested bacterial and fungal strains. Compounds 4j and
4l with the MIC values of 0.0138 µmol/mL exhibited very good potency against C. albicans
and A. niger, respectively. The docking interactions of most active compound 4j with S.
aureus DNA gyrase complexed with DNA and antifungal target Lanosterol 14-α demethylase
explained the good activity. Therefore, compounds 4j can be exploited for further
development of urea-1,2,3-triazole-amide hybrid based lead.
4. Materials and methods
4.4.
4.4.1. General
Some of the chemicals used in synthesis were purchased commercially and some were
Experimental section
synthesized in the laboratory. Open capillaries were used for determination of melting points
and the recorded mp’s are reported as such. Silica plated aluminium sheets (SIL G/UV254,
ALUGRAM) were used for monitoring the reaction which were then visualized under
Ultraviolet lamp. SHIMAZDU IR AFFINITY-I FTIR spectrophotometer was used for
recording the IR spectra within the range of 400-4000 cm-1. Bruker 400 MHz spectrometer
was used for interpreting the NMR spectra relative to Me4Si as standard. Chemical shift
values were reported in ppm and coupling constant values in Hz. Two dimensional analysis
1
13
was also carried out for assessment of H and C signals in the NMR spectra. DEPT-135
(distortionless enhancement in polarisation transfer), COSY, HMQC (heteronuclear multiple
19
quantum coherence), HMBC (heteronuclear multiple bond correlation) and F NMR spectra
were also recorded. SCIEX-QTOF spectrometer was used for recording the HRMS of
compounds formed.
4.4.2. General procedure for the synthesis of urea-alkynes 2(a-c) [49]:

A solution of substituted phenyl isocyanates 1(a-c) in dry dichloromethane (1.0
mmol) was added dropwise to an ice-cooled solution of propargyl amine (1.1 mmol) and
triethylamine (1.1 mmol) in dichloromethane (20 mL). The reaction mixture was stirred for
one hour and the progress of the reaction was monitored by TLC. After completion of the
reaction solvent was evaporated under reduced pressure and the white solid thus obtained was
washed with ice cooled 2N H2SO4, cold water followed by ice cooled NaHCO3 solution to
yield the urea-alkynes 2(a-c).
4.4.2.1.
1-(4-Fluoro-phenyl)-3-prop-2-ynyl-urea (2a). Yield 80%, White solid; mp
168-170 °C; IR (KBr, νmax/cm-1): 3298 (NH str), 2915, 2122 (C≡C str), 1633 (C=O str), 1509,
1
1408, 1314, 1203, 1100, 946, 869, 838, 650. H NMR (400 MHz, DMSO): δ 8.62 (s, 1H,
NH), 7.40 (dd, J = 9.1, 5.0 Hz, 2H), 7.07 (t, J = 8.9 Hz, 2H), 6.46 (s, 1H, NH towards
propargyl group), 3.88 (dd, J = 5.7, 2.4 Hz, 2H, -NCH2-), 3.10 (t, J = 2.3 Hz, 1H, CH). 13C
NMR (100 MHz, DMSO): δ 29.71, 75.14, 77.77, 115.64, 115.87, 133.36, 158.00, 160.42.
4.4.2.2.
1-(4-Chloro-phenyl)-3-prop-2-ynyl-urea (2b). Yield 82%, White solid; mp
162-165 °C; IR (KBr, νmax/cm-1): 3323 (NH str), 2135 (C≡C str), 1635 (C=O str), 1570, 1400,
1
1304, 1286, 1241, 1090, 834, 675, 641. H NMR (400 MHz, DMSO): δ 8.73 (s, 1H, NH),
7.43 (d, J = 8.8 Hz, 2H, =C-H), 7.27 (d, J = 8.8 Hz, 2H, =C-H), 6.51 (t, J = 5.4 Hz, 1H, NH
towards propargyl group), 3.88 (dd, J = 5.5, 2.1 Hz, 2H, -NCH2-), 3.10 (t, J = 2.2 Hz, 1H,
CH). 13C NMR (101 MHz, DMSO): δ 154.91, 139.54, 129.17, 125.39, 119.77, 82.53, 73.34,
29.23.
4.4.2.3.
1-(4-Methoxy-phenyl)-3-prop-2-ynyl-urea (2c) [49]: Yield 84%, White solid;
mp 168-172 °C; IR (KBr, νmax /cm-1): 3337 (NH str), 2961, 2139 (C≡C str), 1608 (C=O str),
1523, 1428, 1362, 1245, 1181, 1032, 913, 828, 774, 633. 1H NMR (400 MHz, DMSO): δ 8.36
(s, 1H, NH), 7.29 (d, J = 8.9 Hz, 2H, =CH), 6.82 (d, J = 8.9 Hz, 2H, =CH), 6.34 (t, J = 5.6 Hz,
1H, NH), 3.87 (dd, J = 5.6, 2.2 Hz, 2H, NH towards propargyl group), 3.70 (s, 3H, -NCH2-),
13
3.08 (t, J = 2.0 Hz, 1H, CH). C NMR (101 MHz, DMSO): δ 155.45, 154.61, 133.71,
120.12, 114.36, 82.69, 73.13, 55.60, 29.22.
4.4.3. General procedure for the synthesis of urea-1,2,3-triazole-amide hybrids 4(a-r):
Urea linked alkynes 2(a-c) (1.0 mmol), 2-bromo-N-phenylacetamides 3(a-f) (1.0 mmol) were
dissolved in dimethylformamide (4 mL) in a round bottom flask. Sodium azide (3.0 mmol) in
water (2 mL) copper sulphate (0.02 mmol) in water (2 mL) were added to the reaction mixture

followed by addition of sodium ascorbate (0.02 mmol) and the mixture was stirred at 40 ºC
for 2-3 hours. After completion of the reaction, reaction mixture was filtered and the solid
obtained was washed with ice cold water and small amount of ethyl acetate to yield triazole
hybrids 4(a-r).
4.4.3.1.
N-(2-Fluoro-phenyl)-2-{4-[3-(4-fluoro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-
yl}-acetamide (4a). Yield 88%, White solid; mp 280-285 °C; IR (KBr, νmax /cm-1): 3327 (NH
str), 3125 (NH str), 3069 (C-H str, triazole), 1672 (C=O str), 1661 (C=O str), 1572 (C=C str),
1555, 1504, 1458, 1413, 1300, 1221, 1061, 827, 789. 1H NMR (400 MHz, DMSO): δ 10.29 (s,
1H, NH), 8.62 (s, 1H, NH), 7.99 (s, 1H, triazolyl-H), 7.91 (t, J = 8.5 Hz, 1H), 7.41 (dd, J =
8.7, 5.0 Hz, 2H), 7.30 (t, J = 10.2 Hz, 1H), 7.21 – 7.14 (m, 2H), 7.06 (t, J = 8.8 Hz, 2H), 6.61
(t, J = 5.5 Hz, 1H, NH), 5.40 (s, 2H, -CH2-), 4.36 (d, J = 5.5 Hz, 2H, NCH2). 13C NMR (101
MHz, DMSO): δ 165.37, 158.65, 156.19, 155.65, 145.87, 137.20, 126.16, 126.09, 126.01,
125.89, 125.00, 124.97, 124.83, 124.21, 119.80, 119.72, 116.18, 115.99, 115.68, 115.46,
52.36, 35.32. HRMS: m/z (M + H)+ cacld. for C18H17F2N6O2: 387.1381 found: 387.1391.
4.4.3.2.
N-(3-Fluoro-phenyl)-2-{4-[3-(4-fluoro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-
yl}-acetamide (4b). Yield 89%, White solid; mp 280-285 °C; IR (KBr, νmax /cm-1): 3310 (NH
str), 3256 (NH str), 3125 (C-H str, triazole), 1699 (C=O str), 1668 (C=O str), 1570 (C=C str),
1556, 1546, 1510, 1446, 1411, 1336, 1284, 1055, 866, 835, 783, 658. 1H NMR (400 MHz,
DMSO): δ 10.66 (s, 1H, 1NH), 8.61 (s, 1H, NH), 7.99 (s, 1H, triazolyl-H), 7.55 (d, J = 11.5
Hz, 1H), 7.43 – 7.35 (m, 3H), 7.30 (d, J = 8.3 Hz, 1H), 7.06 (t, J = 8.9 Hz, 2H), 6.93 (td, J =
13
8.4, 2.0 Hz, 1H), 6.61 (t, J = 5.6 Hz, 1H, NH), 5.33 (s, 2H, -CH2-), 4.36 (s, 2H, NCH2). C
NMR (101 MHz, DMSO): δ 165.17, 163.79, 161.39, 158.58, 156.23, 155.61, 145.89, 140.62,
140.51, 137.21, 137.18, 131.12, 131.03, 124.79, 119.82, 119.74, 116.05, 115.66, 115.44,
110.83, 110.62, 106.66, 106.40, 52.59, 35.33. HRMS: m/z (M + H)+ cacld. for C18H17F2N6O2:
387.1381 found: 387.1391.
4.4.3.3.
N-(4-Fluoro-phenyl)-2-{4-[3-(4-fluoro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-
yl}-acetamide (4c). Yield 86%, White solid; mp 285-290 °C; IR (KBr, νmax /cm-1): 3312 (NH
str), 3275 (NH str), 3140 (C-H str, triazole), 1668 (C=O str), 1663 (C=O str), 1574, 1556,
1
1506, 1501, 1410, 1221, 1055, 837, 808, 648. H NMR (400 MHz, DMSO): δ 10.51 (s, 1H,
NH), 8.62 (s, 1H, NH), 7.99 (s, 1H, triazolyl-H), 7.60 (dd, J = 9.1, 5.0 Hz, 2H), 7.41 (dd, J =
9.1, 5.0 Hz, 2H), 7.18 (t, J = 8.9 Hz, 2H), 7.06 (t, J = 8.9 Hz, 2H), 6.61 (t, J = 5.6 Hz, 1H,

13
NH), 5.30 (s, 2H, -CH2-), 4.36 (d, J = 5.6 Hz, 2H, NCH2). C NMR (101 MHz, DMSO): δ
164.67, 159.88, 158.57, 157.49, 156.21, 155.60, 145.87, 137.21, 137.19, 135.29, 135.26,
124.77, 121.51, 121.43, 119.79, 119.71, 116.08, 115.86, 115.67, 115.45, 52.52, 35.33, 35.23.
HRMS: m/z (M + H)+ cacld. for C18H17F2N6O2: 387.1381 found: 387.1391.
4.4.3.4.
2-{4-[3-(4-Fluoro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(2-
trifluoromethyl-phenyl)-acetamide (4d). Yield 84%, White solid; mp 245-250 °C; IR (KBr,
νmax /cm-1): 3370 (NH str), 3269 (NH str), 3130 (C-H str, triazole), 1676 (C=O str), 1564,
1547, 1508, 1458, 1323, 1269, 1172, 1059, 975, 954, 829, 804, 768, 706, 683. 1H NMR (400
MHz, DMSO): δ 10.10 (s, 1H, NH), 8.61 (s, 1H, NH), 7.97 (s, 1H, triazolyl-H), 7.77 (d, J =
7.7 Hz, 1H), 7.70 (t, J = 7.7 Hz, 1H), 7.57 – 7.46 (m, 2H), 7.40 (dd, J = 9.1, 5.0 Hz, 2H), 7.06
(t, J = 8.9 Hz, 2H), 6.60 (t, J = 5.7 Hz, 1H, NH), 5.37 (s, 2H, -CH2-), 4.35 (d, J = 5.6 Hz, 2H,
13
NCH2). C NMR (101 MHz, DMSO): δ 166.07, 158.56, 156.22, 155.60, 145.87, 137.21,
137.19, 134.91, 133.64, 130.36, 127.63, 126.98, 126.92, 126.86, 125.30, 124.77, 119.79,
119.71, 115.66, 115.44, 52.05, 35.31. HRMS: m/z (M + H)+ cacld. for C19H17F4N6O2:
437.1349 found: 437.1363.
4.4.3.5.
2-{4-[3-(4-Fluoro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(3-
trifluoromethyl-phenyl)-acetamide (4e). Yield 83%, White solid; mp 278-280 °C; IR (KBr,
νmax /cm-1): 3310 (NH str), 3163 (NH str), 3132 (C-H str, triazole), 1688 (C=O str), 1672
(C=O str), 1572, 1551, 1503, 1458, 1325, 1173, 1061, 964, 885, 837, 804, 760, 694. 1H NMR
(400 MHz, DMSO): δ 10.81 (s, 1H, NH), 8.62 (s, 1H, NH), 8.07 (s, 1H), 8.01 (s, 1H), 7.76 (d,
J = 8.4 Hz, 1H), 7.58 (d, J = 8.0 Hz, 1H), 7.47 – 7.38 (m, 3H), 7.06 (t, J = 8.9 Hz, 2H), 6.61
(t, J = 5.7 Hz, 1H, NH), 5.36 (s, 2H, -CH2-), 4.37 (d, J = 5.7 Hz, 2H, NCH2). 13C NMR (101
MHz, DMSO): δ 165.46, 158.57, 156.21, 155.61, 145.91, 139.63, 137.21, 137.19, 130.69,
130.20, 129.88, 129.57, 125.82, 124.82, 123.26, 123.11, 120.61, 120.57, 119.80, 119.72,
115.77, 115.73, 115.66, 115.44, 52.58, 35.33. HRMS: m/z (M + H)+ cacld. for C19H17F4N6O2:
437.1349 found: 437.1363.
4.4.3.6.
2-{4-[3-(4-Fluoro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(4-
trifluoromethyl-phenyl)-acetamide (4f). Yield 86%, White solid; mp 285-290 °C; IR (KBr,
νmax /cm-1): 3331 (NH str), 3269 (NH str), 3138 (C-H str, triazole), 1670 (C=O str), 1667
1
(C=O str), 1572, 1555, 1508, 1470, 1329, 1300, 1227, 1065, 843, 804, 708, 644. H NMR
(400 MHz, DMSO): δ 10.82 (s, 1H, NH), 8.63 (s, 1H, NH), 8.01 (s, 1H, triazolyl-H), 7.80 (d,

J = 8.6 Hz, 2H), 7.71 (d, J = 8.7 Hz, 2H), 7.41 (dd, J = 9.0, 5.0 Hz, 2H), 7.06 (t, J = 8.9 Hz,
13
2H), 6.62 (t, J = 5.5 Hz, 1H, NH), 5.37 (s, 2H, -CH2-), 4.37 (d, J = 5.6 Hz, 2H, NCH2). C
NMR (101 MHz, DMSO): δ 165.49, 158.54, 156.21, 155.61, 145.93, 142.45, 137.21, 126.73,
126.69, 126.09, 124.83, 124.37, 124.05, 123.39, 119.79, 119.72, 119.63, 115.66, 115.44,
52.63, 35.33. HRMS: m/z (M + H)+ cacld. for C19H17F4N6O2: 437.1349 found: 437.1363.
4.4.3.7.
2-{4-[3-(4-Chloro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(2-fluoro-
phenyl)-acetamide (4g). Yield 87%, White solid; mp 277-279 °C; IR (KBr, νmax /cm-1): 3356
(NH str), 3258 (NH str), 3130 (C-H str, triazole), 1666 (C=O str), 1661 (C=O str), 1597, 1555,
1
1491, 1458, 1317, 1061, 972, 817, 752, 698, 637. H NMR (400 MHz, DMSO): δ 10.28 (s,
1H, NH), 8.74 (s, 1H, NH), 7.99 (s, 1H, triazolyl-H), 7.91 (t, J = 8.7 Hz, 1H), 7.44 (d, J = 8.8
Hz, 2H), 7.28 (t, J = 7.6 Hz, 3H), 7.20 – 7.15 (m, 2H), 6.67 (t, J = 5.5 Hz, 1H, NH), 5.40 (s,
2H, -CH2-), 4.37 (d, J = 5.5 Hz, 2H, NCH2). 13C NMR (101 MHz, DMSO): δ 165.34, 155.40,
155.13, 152.69, 145.75, 139.85, 128.93, 126.15, 126.08, 126.00, 125.88, 125.06, 124.98,
124.94, 124.83, 124.21, 119.63, 116.16, 115.97, 52.37, 35.32. HRMS: m/z (M + H)+ cacld. for
C18H17ClFN6O2: 403.1086 found: 403.1326.
4.4.3.8.
2-{4-[3-(4-Chloro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(3-fluoro-
phenyl)-acetamide (4h). Yield 83%, White solid; mp 290-292 °C; IR (KBr, νmax /cm-1): 3345
(NH str), 3302 (NH str), 3102 (C-H str, triazole), 1697 (C=O str), 1670 (C=O str), 1599, 1555,
1
1491, 1447, 1343, 1059, 972, 868, 819, 783, 731, 706, 682, 640, 606. H NMR (400 MHz,
DMSO): δ 10.67 (s, 1H, NH), 8.74 (s, 1H, NH), 8.00 (s, 1H, triazolyl-H), 7.56 (dt, J = 11.6,
2.1 Hz, 1H), 7.46 – 7.42 (m, 2H), 7.41 – 7.35 (m, 1H), 7.32 – 7.25 (m, 3H), 6.93 (td, J = 8.3,
1.9 Hz, 1H), 6.67 (t, J = 5.6 Hz, 1H, NH), 5.33 (s, 2H, -CH2-), 4.37 (d, J = 5.6 Hz, 2H,
13
NCH2). C NMR (101 MHz, DMSO): δ 165.17, 163.79, 161.39, 155.40, 145.78, 140.62,
140.51, 139.85, 131.12, 131.06, 128.93, 125.06, 124.81, 119.64, 115.46, 115.44, 110.83,
110.62, 106.65, 106.39, 52.59, 35.32. HRMS: m/z (M + H)+ cacld. for C18H17ClFN6O2:
403.1086 found: 403.1326.
4.4.3.9.
2-{4-[3-(4-Chloro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(4-fluoro-
phenyl)-acetamide (4i). Yield 90%, White solid; mp 248-250 °C; IR (KBr, νmax /cm-1): 3329
(NH str), 3271 (NH str), 3140 (C-H str, triazole), 1672 (C=O str), 1663 (C=O str), 1597, 1557,
1
1510, 1470, 1300, 1055, 837, 820, 729, 642. H NMR (400 MHz, DMSO): δ 10.51 (s, 1H,
NH), 8.74 (s, 1H, NH), 7.99 (s, 1H, triazolyl-H), 7.59 (dd, J = 9.0, 5.0 Hz, 2H), 7.43 (d, J =

8.9 Hz, 2H), 7.27 (d, J = 8.9 Hz, 2H), 7.18 (t, J = 8.9 Hz, 2H), 6.67 (t, J = 5.6 Hz, 1H, NH),
5.30 (s, 2H, -CH2-), 4.36 (d, J = 5.6 Hz, 2H, NCH2). 13C NMR (101 MHz, DMSO): δ 164.66,
159.89, 157.50, 155.40, 145.75, 139.83, 139.67, 135.26, 128.93, 125.08, 124.80, 121.54,
121.46, 119.78, 119.65, 116.08, 115.86, 73.27, 52.52, 35.30. HRMS: m/z (M + H)+ cacld. for
C18H17ClFN6O2: 403.1086 found: 403.1326.
4.4.3.10.
2-{4-[3-(4-Chloro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(2-
trifluoromethyl-phenyl)-acetamide (4j). Yield 81%, White solid; mp 250-252 °C; IR (KBr,
νmax /cm-1): 3318 (NH str), 3213 (NH str), 3129 (C-H str, triazole), 1668 (C=O str), 1663
(C=O str), 1593, 1562, 1545, 1493, 1321, 1057, 808, 768, 735, 650, 602. 1H NMR (400 MHz,
DMSO): δ 10.11 (s, 1H, NH), 8.73 (s, 1H, NH), 7.97 (s, 1H, triazolyl-H), 7.77 (d, J = 7.8 Hz,
1H), 7.70 (t, J = 7.6 Hz, 1H), 7.57 – 7.46 (m, 2H), 7.43 (d, J = 8.9 Hz, 2H), 7.26 (d, J = 8.9
Hz, 2H), 6.66 (t, J = 5.6 Hz, 1H, NH), 5.37 (s, 2H, -CH2-), 4.36 (d, J = 5.6 Hz, 2H, NCH2).
13C NMR (101 MHz, DMSO): δ 166.07, 155.42, 145.78, 139.84, 134.88, 133.64, 130.35,
128.94, 127.65, 126.92, 126.87, 126.84, 125.31, 125.09, 124.79, 119.67, 52.07, 35.30. HRMS:
m/z (M + H)+ cacld. for C19H17ClF3N6O2: 453.1054 found: 453.1307.
4.4.3.11.
2-{4-[3-(4-Chloro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(3-
trifluoromethyl-phenyl)-acetamide (4k). Yield 79%, White solid; mp 288-290 °C; IR (KBr,
νmax /cm-1): 3304 (NH str), 3269 (NH str), 3102 (C-H str, triazole), 1674 (C=O str), 1632
(C=O str), 1601, 1555, 1495, 1460, 1335, 1065, 812, 691, 652. 1H NMR (400 MHz, DMSO):
δ 10.80 (s, 1H, NH), 8.74 (s, 1H, NH), 8.07 (s, 1H), 8.01 (s, 1H), 7.76 (d, J = 8.2 Hz, 1H),
7.59 (t, J = 8.0 Hz, 1H), 7.45 (dd, J = 7.3, 5.3 Hz, 3H), 7.27 (d, J = 8.8 Hz, 2H), 6.67 (t, J =
5.5 Hz, 1H, NH), 5.36 (s, 2H, -CH2-), 4.37 (d, J = 5.6 Hz, 2H, NCH2). 13C NMR (101 MHz,
DMSO): δ 165.46, 155.41, 145.81, 139.86, 139.64, 130.70, 130.21, 129.90, 128.94, 125.83,
125.08, 124.84, 123.29, 123.12, 120.55, 119.65, 115.79, 52.60, 35.33. HRMS: m/z (M + H)+
cacld. for C19H17ClF3N6O2: 453.1054 found: 453.1307.
4.4.3.12.
2-{4-[3-(4-Chloro-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(4-
trifluoromethyl-phenyl)-acetamide (4l). Yield 86%, White solid; mp 295-298 °C; IR (KBr,
νmax /cm-1): 3306 (NH str), 3267 (NH str), 3136 (C-H str, triazole), 1668 (C=O str), 1662
1
(C=O str), 1597, 1557, 1493, 1468, 1329, 1063, 841, 812, 735, 706, 646, 602. H NMR (400
MHz, DMSO): δ 10.82 (s, 1H, NH), 8.74 (s, 1H, NH), 8.01 (s, 1H, triazolyl-H), 7.79 (d, J =
8.6 Hz, 2H, =CH), 7.71 (d, J = 8.7 Hz, 2H, =CH), 7.44 (d, J = 8.9 Hz, 2H, =CH), 7.27 (d, J =

8.9 Hz, 2H, =CH), 6.68 (t, J = 5.6 Hz, 1H, NH), 5.37 (s, 2H, -CH2-), 4.38 (d, J = 5.6 Hz, 2H,
13
NCH2). C NMR (101 MHz, DMSO): δ 165.48, 155.43, 145.82, 142.43, 139.85, 128.94,
126.73, 126.70, 126.10, 125.10, 124.86, 124.42, 123.40, 119.67, 52.65, 35.32. HRMS: m/z (M
+ H)+ cacld. for C19H17ClF3N6O2: 453.1054 found: 453.1307.
4.4.3.13.
N-(2-Fluoro-phenyl)-2-{4-[3-(4-methoxy-phenyl)-ureidomethyl]-[1,2,3]triazol-
1-yl}-acetamide (4m). Yield 89%, White solid; mp 270-275 °C; IR (KBr, νmax /cm-1): 3308
(NH str), 3262 (NH str), 3134 (C-H str, triazole), 1674 (C=O str), 1638 (C=O str), 1601, 1555,
1
1513, 1460, 1300, 1053, 831, 799, 756, 660. H NMR (400 MHz, DMSO): δ 10.29 (s, 1H,
NH), 8.37 (s, 1H, NH), 7.98 (s, 1H, triazolyl-H), 7.90 (dd, J = 12.0, 5.7 Hz, 1H), 7.32 – 7.27
(m, 3H), 7.21 – 7.15 (m, 2H), 6.84 – 6.80 (m, 2H), 6.50 (t, J = 5.7 Hz, 1H, NH), 5.40 (s, 2H, -
CH2-), 4.35 (d, J = 5.6 Hz, 2H, NCH2), 3.69 (s, 3H, OCH3). 13C NMR (101 MHz, DMSO): δ
165.37, 155.79, 154.48, 146.01, 133.96, 126.12, 124.97, 124.79, 124.25, 119.94, 116.17,
115.98, 114.36, 55.61, 52.30, 35.29. HRMS: m/z (M + H)+ cacld. for C19H20FN6O3: 399.1581
found: 399.1799.
4.4.3.14.
N-(3-Fluoro-phenyl)-2-{4-[3-(4-methoxy-phenyl)-ureidomethyl]-[1,2,3]triazol-
1-yl}-acetamide (4n). Yield 78%, White solid; mp 268-270 °C; IR (KBr, νmax /cm-1): 3331
(NH str), 3281 (NH str), 3102 (C-H str, triazole), 1692 (C=O str), 1636 (C=O str), 1606, 1564,
1
1510, 1467, 1302, 1059, 970, 874, 816, 779, 762, 710, 681, 637, 608. H NMR (400 MHz,
DMSO): δ 10.67 (s, 1H, NH), 8.37 (s, 1H, NH), 7.99 (s, 1H, triazolyl-H), 7.58 – 7.53 (m, 1H),
7.38 (td, J = 8.2, 6.8 Hz, 1H), 7.30 (d, J = 9.0 Hz, 3H), 6.93 (td, J = 8.5, 2.6 Hz, 1H), 6.85 –
6.80 (m, 2H), 6.50 (t, J = 5.7 Hz, 1H, NH), 5.33 (s, 2H, -CH2-), 4.36 (d, J = 5.6 Hz, 2H,
NCH2), 3.70 (s, 3H, OCH3). 13C NMR (101 MHz, DMSO): δ 165.18, 163.81, 161.40, 155.80,
154.50, 146.05, 140.63, 140.52, 133.96, 131.13, 131.04, 124.78, 119.96, 115.49, 114.37,
110.85, 110.64, 106.68, 106.42, 55.62, 52.59, 35.33. HRMS: m/z (M + H)+ cacld. for
C19H20FN6O3: 399.1581 found: 399.1799.
4.4.3.15.
N-(4-Fluoro-phenyl)-2-{4-[3-(4-methoxy-phenyl)-ureidomethyl]-[1,2,3]triazol-
1-yl}-acetamide (4o). Yield 87%, White solid; mp 280-285 °C; IR (KBr, νmax /cm-1): 3345
(NH str), 3275 (NH str), 3140 (C-H str, triazole), 1668 (C=O str), 1641 (C=O str), 1607, 1566,
1
1510, 1464, 1339, 1053, 837, 806, 770, 654. H NMR (400 MHz, DMSO): δ 10.50 (s, 1H,
NH), 8.36 (s, 1H, NH), 7.98 (s, 1H, triazolyl-H), 7.60 (dd, J = 9.1, 5.0 Hz, 2H), 7.32 – 7.28
(m, 2H), 7.18 (t, J = 8.9 Hz, 2H), 6.85 – 6.79 (m, 2H), 6.50 (t, J = 5.7 Hz, 1H, NH), 5.30 (s,

13
2H, -CH2-), 4.35 (d, J = 5.6 Hz, 2H, NCH2), 3.70 (s, 3H, OCH3). C NMR (101 MHz,
DMSO): δ 164.68, 157.49, 155.79, 154.48, 146.01, 135.28, 133.95, 124.75, 121.55, 121.48,
119.95, 116.09, 115.87, 114.36, 55.61, 52.53, 35.33. HRMS: m/z (M + H)+ cacld. for
C19H20FN6O3: 399.1581 found: 399.1799.
4.4.3.16.
2-{4-[3-(4-Methoxy-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(2-
trifluoromethyl-phenyl)-acetamide (4p). Yield 81%, White solid; mp 240-245 °C; IR (KBr,
νmax /cm-1): 3341 (NH str), 3308 (NH str), 3108 (C-H str, triazole), 1667 (C=O str), 1636
(C=O str), 1566, 1510, 1462, 1412, 1319, 1051, 827, 806, 770, 648, 606. 1H NMR (400 MHz,
DMSO): δ 10.10 (s, 1H, NH), 8.36 (s, 1H, NH), 7.96 (s, 1H, triazolyl-H), 7.77 (d, J = 7.8 Hz,
1H), 7.70 (t, J = 7.7 Hz, 1H), 7.57 – 7.46 (m, 2H), 7.32 – 7.27 (m, 2H), 6.85 – 6.79 (m, 2H),
6.49 (t, J = 5.7 Hz, 1H, NH), 5.37 (s, 2H, -CH2-), 4.35 (d, J = 5.7 Hz, 2H, NCH2), 3.69 (s, 3H,
13
OCH3). C NMR (101 MHz, DMSO): δ 166.06, 160.08, 155.79, 154.48, 146.02, 134.90,
133.94, 133.63, 130.34, 127.63, 126.91, 125.30, 124.73, 122.59, 119.96, 114.35, 55.61, 52.07,
35.32. HRMS: m/z (M + H)+ cacld. for C20H20F3N6O3: 449.1549 found: 449.1764.
4.4.3.17.
2-{4-[3-(4-Methoxy-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(3-
trifluoromethyl-phenyl)-acetamide (4q). Yield 88%, White solid; mp 282-286 °C; IR (KBr,
νmax /cm-1): 3314 (NH str), 3207 (NH str), 3112 (C-H str, triazole), 1688 (C=O str), 1668
(C=O str), 1605, 1564, 1514, 1450, 1335, 1063, 835, 804, 696, 662, 604. 1H NMR (400 MHz,
DMSO): δ 10.80 (s, 1H, NH), 8.37 (s, 1H, NH), 8.07 (s, 1H, triazolyl-H), 7.99 (s, 1H, =C-H),
7.76 (d, J = 8.2 Hz, 1H, =C-H), 7.59 (t, J = 8.0 Hz, 1H, =C-H), 7.45 (d, J = 7.8 Hz, 1H, =C-
H), 7.30 (d, J = 9.1 Hz, 2H, =C-H), 6.82 (d, J = 9.1 Hz, 2H, =C-H), 6.50 (t, J = 5.7 Hz, 1H,
NH), 5.35 (s, 2H, -CH2-), 4.36 (d, J = 5.7 Hz, 2H, NCH2), 3.70 (s, 3H, OCH3). 13C NMR (101
MHz, DMSO): δ 165.47, 155.79, 154.47, 146.07, 139.65, 133.97, 130.70, 130.21, 129.90,
125.83, 124.80, 123.28, 120.58, 119.93, 115.79, 114.35, 55.60, 52.59, 35.33. HRMS: m/z (M
+ H)+ cacld. for C20H20F3N6O3: 449.1549 found: 449.1764.
4.4.3.18.
2-{4-[3-(4-Methoxy-phenyl)-ureidomethyl]-[1,2,3]triazol-1-yl}-N-(4-
trifluoromethyl-phenyl)-acetamide (4r). Yield 85%, White solid; mp 290-293 °C; IR (KBr,
νmax /cm-1): 3310 (NH str), 3130 (C-H str, triazole), 3112 (NH str), 1688 (C=O str), 1682
1
(C=O str), 1605, 1568, 1516, 1464, 1325, 1069, 839, 802, 768, 716, 658, 617. H NMR (400
MHz, DMSO): δ 10.81 (s, 1H, NH), 8.37 (s, 1H, NH), 8.00 (s, 1H, triazolyl-H), 7.79 (d, J =
8.6 Hz, 2H, =CH), 7.71 (d, J = 8.7 Hz, 2H, =CH), 7.30 (d, J = 9.0 Hz, 2H, =CH), 6.82 (d, J =

9.0 Hz, 2H, =CH), 6.51 (t, J = 5.6 Hz, 1H, NH), 5.36 (s, 2H, -CH2-), 4.36 (d, J = 5.6 Hz, 2H,
NCH2), 3.70 (s, 3H, OCH3). 13C NMR (101 MHz, DMSO): δ 165.49, 155.81, 154.56, 146.08,
142.49, 133.97, 126.73, 126.69, 124.80, 119.97, 119.69, 114.38, 55.63, 52.64, 35.34. HRMS:
m/z (M + H)+ cacld. for C20H20F3N6O3: 449.1549 found: 449.1764.
4.5.
Antimicrobial Evaluation
The antimicrobial activities were carried out by standard serial dilution following the
procedure as reported by Kaushik et al. [54].
4.6. Docking details
The Docking studies of compound 4l were carried out by following procedure as given by
Kaushik et al. using Auto Dock Vina 1.1.2. [54]
Conflict of interest
The authors declare that they have no conflict of interest.
Acknowledgement
This work was carried out under the financial support from Haryana State Council for
Science & Technology (HSCST) in the form of Junior Research Fellowship (Nisha Poonia)
and PURSE program No. SR/PURSE2/40(G), DST, New Delhi. The authors are also thankful
to APJ Abdul Kalam Central instrumentation laboratory, Guru Jambheshwar University of
Science & Technology, Hisar, India for NMR, MS spectra of the compounds, respectively.
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Highlights
•
•
•
•
A series of urea-1,2,3-triazole-amide hybrids was synthesized.
Most of the hybrids displayed good antimicrobial potential.
The attachment of triazole ring with urea exhibit synergistic activity.
Docking studies of hybrid 4j to antibacterial and antifungal target was carried out.

Design, Synthesis, Antimicrobial Evaluation and Docking Studies of Urea-Triazole-Amide
Hybrids
Kashmiri Lal,1* Nisha Poonia,1 Poonam Rani,1 Ashwani Kumar,2 and Anil Kumar3
Authors declare no conflict of interest.