Design, synthesis, antimicrobial activity and anti-HIV activity evaluation of novel hybrid quinazoline-triazine derivatives

Article abstract of DOI:10.3109/14756366.2012.755622

A series of novel hybrid quinazoline-triazine derivatives was designed and synthesized from cyanuric chloride and anthranilic acid through sequential reactions, which contain different pharmacophores like quinazoline and substituted diaryl triazine (DATA)

Full text of DOI:10.3109/14756366.2012.755622

http://informahealthcare.com/enz
ISSN: 1475-6366 (print), 1475-6374 (electronic)
J Enzyme Inhib Med Chem, Early Online: 1–9
2013 Informa UK Ltd. DOI: 10.3109/14756366.2012.755622
!
RESEARCH ARTICLE
Design, synthesis, antimicrobial activity and anti-HIV activity evaluation
of novel hybrid quinazoline–triazine derivatives
Rahul P. Modh1, Erik De Clercq2, Christophe Pannecouque2, and Kishor H. Chikhalia1
2
1Department of Chemistry, University School of Sciences, Gujarat University, Ahmedabad, Gujarat, India, and Department of Microbiology and
Immunology, Rega Institute for Medical Research, Leuven, Belgium
Abstract
Keywords
A series of novel hybrid quinazoline–triazine derivatives was designed and synthesized from
cyanuric chloride and anthranilic acid through sequential reactions, which contain different
pharmacophores like quinazoline and substituted diaryl triazine (DATA) linked with ethylene
diamine. All the newly synthesized compounds were characterized by infrared, 1H-NMR, 13C-
NMR, MS and elemental analysis. Further, we evaluated the in vitro anti-HIV activity of the newly
synthesized compounds against HIV-1 (IIIB) and HIV-2 (ROD) viral strains and as well as in vitro
antimicrobial activity against four bacteria (Staphylococcus aureus, Bacillus cereus, Pseudomonas
aeruginosa, Klebsiella pneumoniae) and two fungi (Aspergillus clavatus, Candida albicans) using
the paper agar streak dilution method. The bioassay results indicate that four compounds
namely 7d, 7n, 7r and 7s could be considered as possible potential agents.
Anti-HIV, antimicrobial, diaryl triazine (DATA),
dibromo quinazoline, piperazine
History
Received 30 October 2012
Revised 27 November 2012
Accepted 28 November 2012
Published online 18 January 2013
Introduction
including antimicrobial7–10, antimycobacterial11, anticancer12,13
,
antimalarial14 and anti-HIV (NNRTIs) properties15. The biologi-
cal importance of quinazoline had already stimulated the
medicinal chemists to consider it as a building block due to its
broad range of pharmacological properties, such as antimicro-
Since 2011, the acquired immunodeficiency syndrome (AIDS)
had already claimed the lives of 1.7 million people, 2.5 million
were newly infected with human immunodeficiency virus (HIV)
and 34 million people are still living with HIV1. Due to the
prevalence of drug-resistant viral variants2, the highly active
antiretroviral therapy (HAART) regimen plays a crucial role in
the treatment of HIV-1 infection, typically involving concomitant
treatment with a mixture of nucleoside and non-nucleoside HIV-1
RT (reverse transcriptase) inhibitors resulting in the combination
of three to four drugs. However, drug resistance and side effects
often compromise clinical treatment3. HIV-1 non-nucleoside
reverse transcriptase inhibitors (NNRTIs) have become an
essential part of HAART, with unique antiviral high potency,
low toxicity and exquisite selectivity4. Among the NNRTIs, diaryl
triazine (DATA) derivatives (Figure 1), such as R129385,
R120394 and R106168 displayed high potent activity against
wild- and NNRTI-resistant strains of HIV-1 which has attracted
considerable attention over the past few years5.
bial16–18, anti-HIV and anti-TMV (Tobacco Mosaic Virus)19,20
,
antitubercular21, anticancer22, anti-inflammatory23, anticonvul-
sant24, antidepressant25, hypolipidemic26, antiulcer27, analgesic28
and immunotropic activities29. Moreover, piperazine heterocycles
are valuable structural units in drug research30–36
.
In context to the above rationale and in continuation of our
ongoing program focused on finding new leads with anti-HIV
activities37–42, a novel hybrid series of DATA molecules with a
combination of different pharmacophores such as triazine,
quinazoline and piperazine that are structurally related to anti-
HIV lead compounds, i.e. piperidine linked with DATA-NNRTI
derivatives43, abacavir having cyclopropyl amine group44 and DPC
96145 with quinazoline moiety, are reported (Figure 2). Herein, we
synthesized a new series of ethylene diamine-linked quinazoline–
triazine derivatives starting from the triazine ring of DATA.
The development of hybrid molecules through the arrangement
of dissimilar pharmacophores may provide compounds with
attractive biological profiles6. Several observations indicate that
Materials and methods
s-triazine analogues are the widely studied heterocyclic com- All experiments were conducted under scrupulously dry condi-
pounds owing to their broad spectrum of biological activity, tions and nitrogen atmosphere. All solvents were dried over an
appropriate drying agent. Acetone was dried by heating under
reflux over calcium hydride for several days followed by
Address for correspondence: Kishor H. Chikhalia, Department of
distillation. THF was dried by heating under reflux over sodium
Chemistry, University School of Sciences, Gujarat University, Navrang-
and benzophenone followed by distillation. 1,4-Dioxane, ethyl
pura, Ahmedabad 380 009, Gujarat, India. Tel: þ91-79-26305037/
acetate, petroleum ether (fraction 50–70 ꢀC), dichloromethane and
methanol for chromatography were distilled before usage.
9427155529. Fax: þ91-79-26308545. E-mail: chikhalia_kh@yahoo.com
Rahul Modh, Department of Chemistry, University School of Sciences,
Evaporation of solvents was carried out on a rotary evaporator
Gujarat University, Navrangpura, Ahmedabad 380 009, Gujarat, India.
under reduced pressure or using
a high-vacuum pump.
E-mail: rahulmodh@gmail.com

2
R. P. Modh et al.
J Enzyme Inhib Med Chem, Early Online: 1–9
Figure 1. The structures of DATA derivatives.
Analytical thin-layer chromatography was performed on Merck N,N-dimethyl aniline (10 mL, 86.3 mmol) was heated to 60–70 ꢀC
(Mumbai, India) precoated aluminum plates 60 F254 with a using a water bath for 2 h. After completion of the reaction, the
0.2 mm layer of silica gel. NMR spectra were recorded on a 400 excess phosphorus oxychloride was removed under reduced
and 500 MHz spectrometer (Bruker AMX 400, Bruker AV 400, or pressure, crushed ice (20 g) was added to the residue and adjusted
a Bruker DRX 500; San Diego, CA) using DMSO as a solvent and to pH 7–7.5 by 1N NaOH solution. The separated solid was
TMS (Me4Si) as an internal standard. All 1H and 13C NMR filtered, washed with water, dried and crystallized from
chemical shifts are quoted in ppm and were calibrated on solvent dichloromethane affording the product 6,8-dibromo-4-chloroqui-
signals. Multiplicities are given as s (singlet), d (doublet), dd nazoline (3): yield 5.0 g (94%).
(doublet–doublet), q (quadruplet), t (triplet) and m (multiplet).
Liquid chromatography–mass spectrometry (LC/MS) analyses
were performed using Shimadzu (Kyoto, Japan) LC-10AS pumps
N-(6,8-Dibromoquinazolin-4-yl)ethane-1,2-diamine (4)
A
mixture of 6,8-dibromo-4-chloroquinazoline (3) (25 g,
and a SPD-10AV UV-Vis detector (Shimadzu, Kyoto, Japan) with
a Micromass Platform LC spectrometer (Mississippi, MS). LC/
MS methods are detailed below. Preparative reverse phase (RP)
HPLC was performed using two Shimadzu LC-8A pumps (Kyoto,
Japan) and an SPD-10AV UV-Vis detector set at 220 nm on C18
RP columns (YMC Pack ODSA S5 20 ꢁ 100 mm or
30 ꢁ 250 mm; YMC Co. Ltd, Kyoto, Japan) eluting with
methanol/water mixtures buffered with 0.1% trifluoroacetic acid.
77.6 mmol) and 1,2-diaminoethane (28 g, 25.27 mL, 0.4654 mol,
6 equiv.) was stirred under reflux for 8 h. After cooling to room
temperature, the reaction was carried out under the water–ice
mixture. The precipitate formed was filtered off, and the residue
was washed with cold water. The compound was recrystallized
from ethanol: yield 24.9 g (93%).
4,6-Dichloro-N-cyclopropyl-1,3,5-triazin-2-amine (5)
3,5-Dibromo anthranilic acid (1)
Cyanuric chloride (25 g, 0.14 mol) was suspended in chloroben-
zene (125 mL) and cooled to ꢂ10 ꢀC. Cyclopropylamine (8 g,
0.14 mol) was added slowly at ꢂ10 ꢀC for 30 min. Then 30% of
NaOH solution was added dropwise. The reaction mixture was
stirred at ꢂ10 ꢀC for 30 min and allowed to stand for a further 16 h
at room temperature, after which it was washed with water
(2 ꢁ 400 mL), dried over anhydrous sodium sulphate and filtered.
The white crystals of cyclopropylamino-4,6-dichloro-s-triazine
(5) were obtained through removal of the excess chlorobenzene by
vacuum distillation: yield 26.7 g (96%).
Anthranilic acid (50 g, 0.36 mol) was dissolved and refluxed in
glacial acetic acid (100 mL). Bromine (27.5 mL) was added slowly
while reflux; colorless crystals took place. Then cooled to 25ꢀC and
filtered. The solid was rinsed with glacial acetic acid and then with
benzene. The crude product was boiled up five times successively
with 500 mL water, each filtration being made rapidly with suction.
The insoluble residue consisting of the 3,5-dibromoanthranilic acid
constituted two-thirds of the product. The pure acid was obtained
by recrystallizing from alcohol: yield 102.2 g (95%).
4-Chloro-N-cyclopropyl-6-R-1,3,5-triazin-2-amine (6a–6s)
6,8-Dibromoquinazolin-4(3H)-one (2)
A solution of 4,6-dichloro-N-cyclopropyl-1,3,5-triazin-2-amine
(5) (1.0 g, 4.9 mmol), relevant substituted piperazine or piperidine
derivative (4.9 mmol) (presented in the table under Scheme 1) and
potassium carbonate (0.67 g, 4.9 mmol) in dry acetone (10 mL)
was stirred for 5–6 h at room temperature. Progress of the reaction
was monitored by TLC using solvent system toluene:acetone
(8:2). After completion of the reaction, it was poured in the ice–
water mixture, neutralized by dilute HCl and extracted with
CHCl3, washed with water and dried over Na2SO4. The solution
A solution of 3,5-dibromo anthranilic acid (1) (5.00 g, 17 mmol)
in formamide (15 mL, 0.29 mol) was heated slowly to 160 ꢀC and
maintained for 6 h. After the completion of reaction, the mixture
after cooling was poured onto ice-water. The solid separated was
filtered, dried and recrystallized from ethanol to give 6,8-
dibromoquinazolin-4(3H)-one (2): yield 4.0 g (77%).
6,8-Dibromo-4-chloroquinazoline (3)
A mixture of 6,8-dibromoquinazolin-4(3H)-one (2) (5 g, was concentrated under reduced pressure to afford the desire
16.5 mmol), phosphorus oxychloride (10 mL, 39.8 mmol) and product (6a–6s).

DOI: 10.3109/14756366.2012.755622
Antimicrobial and anti-HIV studies of hybrid quinazoline–triazine derivatives
3
Figure 2. The design of quinazoline–triazine hybrid derivatives.
N2-cyclopropyl-N4-(2-(6,8-dibromoquinazolin-4-ylami-
no)ethyl)-6-R-1,3,5-triazine-2,4-diamine (7a–7s)
Pseudomonas aeruginosa MTCC 741, Klebsiella pneumoniae
MTCC 109) and fungal (Aspergillus clavatus MTCC 1323 and
Candida albicans MTCC 183) species were selected and
minimum inhibitory concentration (MIC) of the compound was
determined by the agar streak dilution method46. A stock solution
of the tested compound (200 mg/mL) in dimethylsulfoxide was
prepared and graded quantities of the test compounds were
incorporated in a specified quantity of molten sterile agar, i.e.
nutrient agar for the evaluation of antibacterial and sabouraud
dextrose agar for antifungal activity, respectively. The medium
containing the test compound was poured into a petri dish at a
depth of 4–5 mm and allowed to solidify under aseptic conditions.
A suspension of the respective microorganism of approximately
105 CFU/mL was prepared and applied to plates with serially
diluted compounds with concentrations in the range of 3.125–
200 mg/mL in dimethylsulfoxide and incubated at (37 ꢃ 1) ꢀC for
24 h (bacteria) or 48 h (fungi). The lowest concentration of the
substance that prevents the development of visible growth is
considered to be the MIC value.
A solution of compounds (6a–6s) (1.0 mmol), N-(6,8-dibromo-
quinazolin-4-yl)ethane-1,2-diamine (4) (0.35 g, 1.0 mmol) and
potassium carbonate (0.14 g, 1.0 mmol) in 1,4-dioxane (5 mL) was
refluxed for 12–20 h. Progress of the reaction was monitored by
TLC using toluene:acetone (7:3) as mobile phase. After comple-
tion of the reaction, the mixture was then treated with crushed ice
and neutralized by dilute HCl. The precipitate thus obtained was
filtered off, dried and recrystallized from THF to afford the
desired compounds (7a–7s).
Medicinal chemistry part
In-vitro evaluation of antimicrobial activity
In order to study the antimicrobial properties of the novel
hybrid quinazoline–triazine derivatives, several bacterial
(Staphylococcus aureus MTCC 96, Bacillus cereus MTCC 430,

4
R. P. Modh et al.
J Enzyme Inhib Med Chem, Early Online: 1–9
In vitro evaluation of anti-HIV assay
discarded. The MT-4 cells were resuspended at
a final
concentration of 6 ꢁ 105 cells/mL and 50 mL volumes were
transferred to the microtiter tray wells. After five days of
incubation at 37 ꢀC following infection, the viability of mock- and
HIV-infected cells was examined spectrophotometrically by the
MTT assay.
The evaluation of the anti-HIV activity of the synthesized
compounds against HIV-1 strain (IIIB) and HIV-2 strain (ROD)
in MT-4 cells was performed using the MTT (3-(4,5-dimethylthia-
zol-2-yl)-2,5-diphenyl tetrazolium bromide) assay method as
earlier reported47,48. In brief, stock solutions (10 times final
concentration) of test compounds were added in 25 mL volumes to
two series of triplicate wells so as to allow simultaneous
evaluation of their effects in mock- and HIV-infected cells at
the beginning of each experiment. Serial fivefold dilutions of test
compounds were made directly in flat-bottomed 96-well micro-
titer trays using a Biomek 3000 robot (Beckman Instruments,
Fullerton, CA). Untreated control HIV- and mock-infected cell
samples were included for each sample. HIV-1(IIIB)49 or HIV-2
(ROD)50 stock (50 mL) at 100–300 CCID50 (50% cell culture
infectious dose) or culture medium was added to either the
infected or mock-infected wells of the microtiter tray. Mock-
infected cells were used to evaluate the effects of the test
compounds on uninfected cells in order to assess the cytotoxicity
of the test compounds. Exponentially growing MT-4 cells51 were
centrifuged for 5 min at 1000 rpm (220g) and the supernatant was
The MTT assay is based on the reduction of yellow-coloured
MTT (Acros Organics, Geel, Belgium) by mitochondrial
dehydrogenase of metabolically active cells to a blue–purple
formazan that can be measured spectrophotometrically. The
absorbances were read in an eight-channel computer-controlled
photometer (Safire, Tecan), at two wavelengths (540 and 690 nm).
All data were calculated using the median optical density value of
three wells. The 50% cytotoxic concentration was defined as the
concentration of the test compound that reduced the absorbance
(optical density 540) of the mock-infected control sample by 50%.
The concentration achieving 50% protection from the cytopathic
effect of the virus in infected cells was defined as the 50%
effective concentration. Anti-HIV activity and cytotoxicity of
standard drug ddN/ddI were also performed by a similar method
in MT-4 cells.
Scheme 1. Overview of the synthetic strategy for the synthesis of N2-cyclopropyl-N4-(2-(6,8-dibromoquinazolin-4-ylamino)ethyl)-6-R-1,3,5-triazine-
2,4-diamine (7a–7s).

DOI: 10.3109/14756366.2012.755622
Antimicrobial and anti-HIV studies of hybrid quinazoline–triazine derivatives
5
Scheme 1. Continued.

6
R. P. Modh et al.
J Enzyme Inhib Med Chem, Early Online: 1–9
Table 1. Anti-HIV-1 and HIV-2 activity* (IC50 and CC50 in mg/mL) and
cytotoxicity of compounds 6a–s and 7a–s in MT-4 cells.
Results and discussion
In vitro anti-HIV assay
IC50
CC50
The novel synthesized compounds 6a–s and 7a–s were tested for
their in vitro anti-HIV-1 (strain IIIB) and -HIV-2 (strain ROD)
activity in human T-lymphocyte (MT-4) cells. Inhibitory
concentrations (IC50) of synthesized compounds on HIV-1 and
HIV-2 replications were measured by the inhibition of virus
induced cytopathic effect in MT-4 cells. Cytotoxicity concentra-
tions (CC50) of test compounds in mock infected MT-4 cells were
also measured by the MTT-method. Anti-HIV activity and
cytotoxicity of test compounds were compared with standard
drug, 2H,3H-dideoxynucleosides/20,30-dideoxyinosine (ddN/ddI)
against the replication of HIV-1 and HIV-2 in acutely infected
MT-4 cells. The IC50 value of the synthesized molecules against
HIV-1 and HIV-2 ranged from 2.22 to 113.45 mg/mL whereas the
ddN/ddI inhibitory activities (IC50 4.35 and 6.96 mg/mL) were
considered as standard. Cytotoxic concentration of test com-
pounds ranged from 2.22 to 113.45 mg/mL whereas the
standard drug dd/ddI showed an IC50 of 50 mg/mL in mock-
infected MT-4 cells.
In the present study, some of the test compounds exhibited
cytotoxic concentrations 2-fold higher than the standard drug
ddN/ddI. Among the compounds tested, compounds 6d, 7g, 7h,
7n, 7p, and 7s with IC50 9.70, 2.22, 4.24, 9.56, 5.37 and 7.33 mg/
mL, respectively, were more active against the replication of
HIV-1 and HIV-2 in MT-4 cells. It should be noted that these IC50
values were inferior to the subtoxic concentrations. Besides,
the above data showed no selectivity in anti-HIV activity since the
selectivity index (SI ¼ CC50/IC50) was below 1. Hence, the
reported molecules were by themselves inactive, but may offer
background information for active molecules. The results are
presented in Table 1.
Compound
Strain
(mg/mL)y
475.4
475.4
467.20
467.20
492.25
492.25
49.70
(mg/mL)z
SI x
6a
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ꢄ75.4
ꢄ75.4
67.20
67.20
92.25
92.25
9.70
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
51
6b
6c
6d
6e
6f
49.70
9.70
465.70
465.70
484.88
484.88
498.00
498.00
470.98
470.98
470.00
470.00
441.93
441.93
439.58
439.58
447.53
447.53
452.48
452.48
466.00
466.00
466.38
466.38
468.63
468.63
4122
65.70
65.70
94.88
94.88
98.00
98.00
70.98
70.98
70.00
70.00
41.93
41.93
39.58
39.58
47.53
47.53
52.48
52.48
66.00
66.00
66.38
66.38
68.63
68.63
ꢄ122
ꢄ122
9.03
6g
6h
6i
6j
6k
6l
6m
6n
6o
6p
6q
6r
6s
4122
49.03
49.03
497.4
497.4
45.32
45.32
410.7
Antimicrobial activity
9.03
The biological assay summarized in Table 2 revealed that all the
newly synthesized compounds 6a–s and 7a–s displayed biological
activities vary with the differences in the functional group(s) or
atom(s) attached to the piperazine moiety condensed to the
nucleus. From the bioassay results it can be stated that all new
derivatives showed appreciable antimicrobial activity. In the set of
compounds 6a–s, compounds 6n with diphenyl substituent and 6s
with methoxy substituent were most active against S. aureus and
B. cereus bacteria, respectively, at 12.5 mg/mL of MIC.
Compound 6d with the acetyl group to the piperazine ring
exhibited moderate activity against three bacterial strains
(B. cereus, P. aeruginosa and K. pneumoniae) at 50 mg/mL of
MIC and also compound 6q with bearing trifluoromethyl
substitution showed moderate activity against three bacteria
(S. aureus, P. aeruginosa and K. pneumoniae) at 50 mg/mL of
MIC. Analogues 6b, 6j, 6l and 6r were showed moderate activity
against P. aeruginosa and K. pneumoniae at MIC 50 mg/mL. The
antifungal results revealed that, the synthesized compounds
showed variable degree of inhibition against the tested fungi.
Acetyl substituted to piperazine derivative (6d), 2-fluoro phenyl
group derivative (6o) and 2,3,4-trimethoxy benzyl derivative (6r)
displayed higher activity against C. albicans as well as compound
6i with pyrimidyl ring against A. clavatus at an MIC of 25 mg/mL.
Compound 6c with phenyl and compound 6q with trifluoro-
methyl-substituted phenyl to piperazine nucleus appeared with
moderate to good inhibition for both the tested fungi (C. albicans
and A. clavatus) at 50 mg/mL of MIC, whereas derivatives 6h, 6l,
6o and 6s appeared with moderate to good inhibition against A.
clavatus and derivatives 6j and 6n against C. albicans at an MIC
50 mg/mL. While all the other derivatives in this set of compounds
ꢄ97.4
ꢄ97.4
5.32
7a
7b
7c
7d
7e
7f
5.32
ꢄ10.7
ꢄ10.7
87.75
87.75
49.05
49.05
12.00
12.00
ꢄ11.1
ꢄ11.1
2.22
410.7
487.75
487.75
449.05
449.05
412.00
412.00
411.1
411.1
42.22
42.22
44.24
7g
7h
7i
2.22
4.24
4.24
44.24
433.10
433.10
4104.90
4104.90
458.58
458.58
456.18
456.18
4113.15
4113.15
49.56
33.10
33.10
104.90
104.90
58.58
58.58
56.18
56.18
113.15
113.15
9.56
7j
7k
7l
7m
7n
7o
ROD
IIIB
ROD
49.56
499.43
499.43
9.56
99.43
99.43
(continued )

DOI: 10.3109/14756366.2012.755622
Table 1. Continued.
Antimicrobial and anti-HIV studies of hybrid quinazoline–triazine derivatives
7
exerted poor activity profiles. In the set of compounds 7a–s,
compounds 7d, 7n, 7r and 7s were potentially active against
bacteria (S. aureus and B. cereus) at 6.25 mg/mL of MIC as well as
against (P. aeruginosa and K. pneumonia) at 6.25 mg/mL and
12.5 mg/mL of MIC, respectively. Compound 7p with the 4-fluoro
IC50
CC50
(mg/mL)z
Compound
Strain
(mg/mL)y
SI x
51
7p
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
IIIB
ROD
45.37
45.37
495.63
495.63
477.55
477.55
47.33
47.33
4.35
5.37
5.37
51 phenyl group appeared with significant inhibition of both Gram
7q
95.63
95.63
77.55
77.55
7.33
51
51
positive and Gram negative at 12.5 mg/mL of MIC, whereas
compound 7c with phenyl substituent was effective against
7r
51
S. aureus at 12.5 mg/mL of MIC along with similar efficacy of
51
analog 7p. Derivatives 7f and 7g with electron-withdrawing
51
chloro-substituent had good activity against P. aeruginosa at an
51
7s
7.33
MIC level of 12.5 mg/mL, along with equal potency of compound
7s with electron-donating alkoxy substituent toward the same
bacteria. Derivative 7n, 7r and 7s had lesser fungal activity
against A. clavatus at 12.5 mg/mL, as well as against C. albicans at
25 mg/mL and 50 mg/mL of MIC, respectively, whereas com-
pounds 7i with pyrimidine group and 7m with diphenyl
substituent were also active against A. clavatus at an MIC of
12.5 mg/mL. Analogs 7f and 7g with a chloro-subtituent displayed
good to moderate activity against A. fumigatus at an MIC of
ddN/ddIô
450
450
412
47
6.96
*All data represent mean values for at least two separate experiments.
yConcentration required to protect the cells against viral cytopathogeni-
city by 50% in MT-4 cells.
zConcentration that reduced the normal uninfected MT-4 cell viability by
50%.
xSelectivity index: ratio of CC50/IC50
ôStandard drug.
.
Table 2. In vitro antimicrobial activity in MIC* (mg/mL) of compounds 6a–s and 7a–s.
Gram þve Gram ꢂve
Fungal strains
S. aureus
MTCC 96
B. cereus
MTCC 430
P. aeruginosa
MTCC 741
K. pneumoniae
MTCC 109
A. clavatus
MTCC 1323
C. albicans
MTCC 183
Compound
6a
6b
6c
6d
6e
6f
6g
6h
6i
6j
6k
6l
6m
6n
6o
6p
6q
6r
6s
7a
7b
7c
7d
7e
7f
7g
7h
7i
7j
7k
200
100
25
200
50
100
50
200
100
100
50
25
50
200
50
100
50
200
25
100
50
100
50
50
50
200
50
200
100
200
50
100
50
200
25
200
25
50
50
25
50
12.5
12.5
12.5
25
12.5
12.5
100
50
100
100
50
100
200
25
200
200
50
100
100
200
100
50
200
100
50
25
50
25
100
200
100
25
100
200
100
200
100
12.5
50
100
200
100
200
100
100
200
100
100
50
50
50
50
100
50
100
100
12.5
12.5
100
100
100
100
50
100
100
100
100
25
100
12.5
25
12.5
25
3.125
–
–
200
100
100
100
100
50
100
200
100
50
25
100
200
50
200
100
50
100
50
25
50
25
100
50
25
50
25
25
25
12.5
100
100
50
100
100
100
100
50
100
100
50
100
25
100
100
100
50
25
25
50
25
25
50
–
100
100
12.5
6.25
100
100
100
12.5
50
100
100
100
100
6.25
50
12.5
25
6.25
25
3.125
–
–
100
100
100
50
50
100
100
100
25
100
100
100
100
12.5
100
100
100
12.5
25
100
50
50
12.5
12.5
–
3.125
–
25
100
100
50
100
12.5
100
12.5
100
25
7l
7m
7n
7o
7p
7q
7r
7s
100
12.5
200
12.5
50
50
6.25
3.125
–
12.5
3.125
–
Ciprofloxaciny
Ketoconazoley
DMSO
3.125
–
–
–
Bold values indicates the most significant activity of the representative compound.
*MIC values are given in brackets. MIC (mg/mL) ¼ Minimum inhibitory concentration.
yStandard.

8
R. P. Modh et al.
J Enzyme Inhib Med Chem, Early Online: 1–9
10. Kaswala PB, Chikhalia KH, Shah NK, et al. Design, synthesis and
antimicrobial evaluation of s-triazinyl urea and thiourea derivatives.
Arkivoc 2009;11:326–35.
11. Machakanur SS, Patil BR, Pathan AH, et al. Synthesis, antimicrobial
and antimycobacterial evaluation of star shaped hydrazones derived
from 1,3,5-triazine. Der Pharma Chemica 2012;4:600–7.
12. Menicagli R, Samaritani S, Signore G, et al. In vitro cytotoxic
activities of 2-alkyl-4,6-diheteroalkyl-1,3,5-triazines: new molecules
in anticancer research. J Med Chem 2004;47:4649–52.
25 mg/mL and 50 mg/mL of MIC, respectively. Compounds 5o and
5q with fluoro-substituent showed inhibition against C. albicans
at an MIC of 25 mg/mL. Some analogs were found to exhibit
moderate activity at 425 mg/mL of MIC; however, the activity
level of many analogs was found to increase within the scaffolds
studied in the research work presented here.
Conclusion
13. Garaj V, Puccetti L, Fasolis G, et al. Carbonic anhydrase inhibitors:
novel sulfonamides incorporating 1,3,5-triazine moieties as inhibi-
tors of the cytosolic and tumour-associated carbonic anhydrase
isozymes I, II and IX. Bioorg Med Chem Lett 2005;15:3102–8.
14. Melato S, Prosperi D, Coghi P, et al. A combinatorial approach to
2,4,6-trisubstituted triazines with potent antimalarial activity:
combining conventional synthesis and microwave-assistance.
ChemMedChem 2008;3:873–6.
15. Xiong YZ, Chen FE, Balzarini J, et al. Non-nucleoside HIV-1
reverse transcriptase inhibitors. Part 11: structural modulations of
diaryltriazines with potent anti-HIV activity. Eur J Med Chem
2008;43:1230–6.
In this work, 38 novel ethylenediamine-linked quinazoline–
triazine (DATA) derivatives were synthesized and examined
thoroughly. The outcome showed that the type of group attached
on the s-triazine ring may have a substantial impact on the
biological activities of the aimed compounds. Out of the 38
compounds screened, compounds 7d, 7n, 7r and 7s exhibited
promising in vitro antibacterial and antifungal effects. The
derivatives were also evaluated for their in vitro anti-HIV-1
(strain IIIB) and HIV-2 (strain ROD) activity in human MT-4
cells. No specific anti-HIV activity was detected for any of the
newly synthesized compounds. In general, the compounds showed
improved antibacterial activity when compared to their antifungal
activity. Among these compounds, a clear trend of improved
activity has been shown to be due to the acetyl, dibenzyl,
trimethoxy and mono-methoxy functionality at the nitrogen atom
of piperazine bases condensed to the nucleus. In comparing the
two set of compounds 6a–s and 7a–s, the incorporation of
quinazoline moity linked to triazine via ethylene diamine is
beneficial to antimicrobial activity. In brief, our findings might be
helpful as leads for designing new molecule with potential
bioactivities.
´
16. Bartroli J, Turmo E, Alguero M, et al. New azole antifungals. 3.
synthesis and antifungal activity of 3-substituted-4(3H)-quinazoli-
nones1,2. J Med Chem 1998;41:1869–82.
17. El-Sharief A, Ammar Y, Zahran M, et al. Aminoacids in the
synthesis of heterocyclic systems: the synthesis of triazinoquinazo-
linones, triazepinoquinazolinones and triazocinoquinazolinones of
potential biological interest. Molecules 2001;6:267–78.
18. Modh RP, Patel AC, Chikhalia KH. Design, synthesis biological
evaluation of some novel quinazolinone scaffolds. Med Chem
2012;8:182–92.
19. Purohit DM, Bhuva VR, Shah VH. Synthesis of 5-arylaminosulpho-
N-acetylanthranilic acid, 6-arylaminosulpho-2-methyl-3-amino/3-N-
chloroacetamido/3-N-arylaminoacetamido-4-(3H)-quinazolones as
potential anti-HIV, anticancer and antimicrobial agents. Chem
Indian J 2003;1:233–45.
Acknowledgements
20. Wang Z, Wang M, Yao X, et al. Design, synthesis and antiviral
activity of novel quinazolinones. Eur J Med Chem 2012;53:275–82.
21. Murav’eva KM, Arkhangel’skaya NV, Shchukina MN, et al.
Synthesis and tuberculostatic activity of aminoquinazoline deriva-
tives. Pharm Chem J 1971;5:339–41.
22. Barker (ZENECA Limited) AJ, inventor; Quinazoline derivatives
and their use as anti-cancer agents, European patent EP 0635498;
1995.
Authors are very thankful to Prof. (Mrs) Shobhana K. Menon, Head,
Department of Chemistry and Director, School of Sciences, Gujarat
University, Ahmedabad, India, for her kind cooperation and providing
support and research facilities. Mr Rahul Modh would like to acknowl-
edge UGC New Delhi, for a Junior Research Fellowship and the Zydus
Research Centre for providing spectral data.
Declaration of interest
23. Laddha SS, Bhatnagar SP.
A new therapeutic approach in
Parkinson’s disease: some novel quinazoline derivatives as dual
selective phosphodiesterase 1 inhibitors and anti-inflammatory
agents. Bioorg Med Chem 2009;17:6796–802.
The authors have declared no conflict of interest.
References
24. Aziza MA, Ibrahim MK, El-Helpy AG. Part II. Synthesis of novel-2-
styryl-3-benzylidenimino-4(3H)-quinazolone
expected anticonvulsant activity. Al-Azhar J Pharm Sci 1994;
14:193–201.
25. Jatav V, Mishra P, Kashaw S, Stables JP. CNS depressant and
anticonvulsant activities of some novel 3-[5-substituted 1,3,4-
derivatives
of
1. UNAIDS 2011 World AIDS Day report. Available from: http://
www.unaids.org. [last accessed 30 Oct 2012].
2. Ragno R, Frasca S, Manetti F, et al. HIV-reverse transcriptase
inhibition: inclusion of ligand-induced fit by cross-docking studies. J
Med Chem 2004;48:200–12.
thiadiazole-2-yl]-2-styryl quinazoline-4(3H)-ones. Eur
Chem 2008;43:1945–54.
J Med
3. Hirschel B, Francioli P. Progress and problems in the fight against
AIDS. N Engl J Med 1998;338:906–8.
26. Kurogi Y, Inoue Y, Tsutsumi K, et al. Synthesis and hypolipidemic
activities of novel 2-[4-[(diethoxyphosphoryl)methyl]phenyl]quina-
zolines and 4(3H)-quinazolinones. J Med Chem 1996;39:1433–7.
27. Terashima K, Shimamura H, Kawase A, et al. Studies on antiulcer
agents. IV: antiulcer effects of 2-benzylthio-5, 6, 7, 8-tetrahydro-4
(3H)-quinazolinones and related compounds. Chem Pharm Bull
1995;43:2021–3.
28. Alagarsamy V, Raja Solomon V, Dhanabal K. Synthesis and
pharmacological evaluation of some 3-phenyl-2-substituted-3H-
quinazolin-4-one as analgesic, anti-inflammatory agents. Bioorg
Med Chem 2007;15:235–41.
29. Nawrocka W, Zimecki M. Syntheses of Novel 3-Amino-2(1H)-
thioxo-4(3H)-quinazolinones and evaluation of their immunotropic
activity. Part III. Arch Pharm 1997;330:399–405.
30. Upadhayaya RS, Vandavasi JK, Kardile RA, et al. Novel quinoline
and naphthalene derivatives as potent antimycobacterial agents. Eur
J Med Chem 2010;45:1854–67.
4. De Clercq E. New developments in anti-HIV chemotherapy. Curr
Med Chem 2001;8:1543–72.
5. Das K, Clark AD, Lewi PJ, et al. Roles of conformational and
positional adaptability in structure-based design of TMC125-
R165335 (etravirine) and related non-nucleoside reverse transcrip-
tase inhibitors that are highly potent and effective against wild-type
and drug-resistant HIV-1 variants. J Med Chem 2004;47:2550–60.
6. Muregi FW, Ishih A. Next-generation antimalarial drugs: hybrid
molecules as a new strategy in drug design. Drug Develop Res
2010;71:20–32.
7. Zhou C, Min J, Liu Z, et al. Synthesis and biological evaluation of
novel 1,3,5-triazine derivatives as antimicrobial agents. Bioorg Med
Chem Lett 2008;18:1308–11.
8. Srinivas K, Srinivas U, Bhanuprakash K, et al. Synthesis and
antibacterial activity of various substituted s-triazines. Eur J Med
Chem 2006;41:1240–6.
9. Modh RP, Patel AC, Mahajan DH, et al. Synthesis and evaluation of
novel 4-substituted styryl quinazolines as potential antimicrobial
agents. Arch Pharm 2012;345:964–72.
31. Al-Turkistani AA, Al-Deeb OA, El-Brollosy NR,El-Emam AA.
Synthesis and antimicrobial activity of some novel

DOI: 10.3109/14756366.2012.755622
Antimicrobial and anti-HIV studies of hybrid quinazoline–triazine derivatives
9
5-alkyl-6-substituted uracils and related derivatives. Molecules 42. Desai SD, Desai KR, Chikhalia KH, et al. Synthesis of a novel class
2011;16:4764–74.
32. Ananda Kumar C, Vinaya K, Narendra Sharath Chandra J, et al.
of some 1, 3, 5-triazine derivatives and their anti-HIV activity. Int J
Drug Des Dis 2011;2:361–8.
Synthesis and antimicrobial studies of novel 1-benzhydryl-piper- 43. Chen X, Zhan P, Liu X, et al. Design, synthesis, anti-HIV evaluation
azine sulfonamide and carboxamide derivatives. J Enzyme Inhib
Med Chem 2008;23:462–9.
33. Upadhayaya RS, Sinha N, Jain S, et al. Optically active
and molecular modeling of piperidine-linked amino-triazine deri-
vatives as potent non-nucleoside reverse transcriptase inhibitors.
Bioorg Med Chem 2012;20:3856–64.
antifungal azoles: synthesis and antifungal activity of (2R,3S)-2- 44. Mallal S, Nolan D, Witt C, et al. Association between presence of
(2,4-difluorophenyl)-3-(5-{2-[4-aryl-piperazin-1-yl]-ethyl}-tetrazol-
2-yl/1-yl)-1-[1,2,4]-triazol-1-yl-butan-2-ol. Bioorg Med Chem
2004;12:2225–38.
HLA-B*5701, HLA-DR7, and HLA-DQ3 and hypersensitivity to
HIV-1 reverse-transcriptase inhibitor abacavir. Lancet 2002;
359:727–32.
34. Banerjee D, Yogeeswari P, Bhat P, et al. Novel isatinyl thiosemi- 45. Mutlib A, Chen H, Shockcor J, et al. Characterization of novel
carbazones derivatives as potential molecule to combat HIV-TB
co-infection. Eur J Med Chem 2011;46:106–21.
glutathione adducts of a non-nucleoside reverse transcriptase
inhibitor, (s)-6-chloro-4-(cyclopropylethynyl)-4-(trifluoromethyl)-
3,4-dihydro-2(1h)-quinazolinone (dpc 961), in rats. possible forma-
tion of an oxirene metabolic intermediate from a disubstituted
alkyne. Chem Res Toxicol 2000;13:775–84.
35. Singh KK, Joshi SC, Mathela CS. Synthesis and in vitro
antibacterial activity of N-alkyl and N-aryl piperazine derivatives.
Indian J Chem B 2011;50:196.
36. Kerns RJ, Rybak MJ, Kaatz GW, et al. Structural features of 46. Hawkey P, Lewis DA. Medical bacteriology: a practical approach.
piperazinyl-linked ciprofloxacin dimers required for activity against Oxford, UK: Oxford University Press; 2004.
drug-resistant strains of Staphylococcus aureus. Bioorg Med Chem 47. Baba M, Snoeck R, Pauwels R, De Clercq E. Sulfated polysacchar-
Lett 2003;13:2109–12.
ides are potent and selective inhibitors of various enveloped viruses,
including herpes simplex virus, cytomegalovirus, vesicular stoma-
titis virus, human immunodeficiency virus. Antimicrob Agents
Chemother 1988;32:1742–5.
37. Patel RV, Kumari P, Rajani DP, et al. Antimicrobial, anti-TB,
anticancer and anti-HIV evaluation of new s-triazine-based hetero-
cycles. Future Med Chem 2012;4:1053–65.
38. Patel RB, Desai KR, Chikhalia KH. Synthesis and studies of novel 48. Pannecouque C, Daelemans D, De Clercq E. Tetrazolium-based
homoveratryl based thiohydantoins as antibacterial as well as anti- colorimetric assay for the detection of HIV replication inhibitors:
HIV agents. Indian J Chem B 2006;45B:1716. revisited 20 years later. Nat Protoc 2008;3:427–34.
39. Patel RB, Chikhalia KH, Pannecouque C, Clercq E. Synthesis of 49. Popovic M, Sarngadharan MG, Read E, Gallo RC. Detection,
novel PETT analogues: 3, 4-dimethoxy phenyl ethyl 1, 3, 5-triazinyl
thiourea derivatives and their antibacterial and anti-HIV studies.
J Braz Chem Soc 2007;18:312–21.
isolation, continuous production of cytopathic retroviruses
(HTLV-III) from patients with AIDS and pre-AIDS. Science
1984;224:497–500.
´
40. Patel RB, Chikhalia KH. Synthesis of heterocyclic and non- 50. Barre-Sinoussi F, Chermann JC, Rey F, et al. Isolation
of a T-lymphotropic retrovirus from a patient at risk for
heterocyclic entities as antibacterial and anti-HIV agents. Indian J
Chem B 2006;45B:1871.
41. Mahajan DH, Pannecouque C, De Clercq E, Chikhalia KH.
acquired immune deficiency syndrome (AIDS). Science 1983;
220:868–71.
Synthesis and studies of new 2-(coumarin-4-yloxy)-4, 6-(substi- 51. Miyoshi I, Taguchi H, Kubonishi I, et al. Type C virus-producing
tuted)-s-triazine derivatives as potential anti-HIV agents. Arch
Pharm 2009;342:281–90.
cell lines derived from adult T cell leukemia. Gann Monogr
1982;28:219–28.