Synthesis and biological evaluation of novel N-aryl maleimide derivatives clubbed with α-hydroxyphosphonates

Article abstract of DOI:10.1016/j.ejmech.2014.06.053

A series of novel molecules 5a-g containing N-aryl maleimide and α-hydroxyphosphonate moieties were synthesized. A distinct approach for high-yielding synthesis of α-hydroxyphosphonates has been discovered using various catalyst and solvents. The structures of the synthesized compounds were elucidated by IR, NMR, MS and CHN analysis. All the synthesized compounds were tested for qualitative (Zone of inhibition) and quantitative (MIC) antimicrobial activities against two pathogenic bacteria such as Bacillus subtilis (NCIM 2250) and Escherichia coli (ATCC 25922) and four pathogenic fungi such as Candida albicans (MTCC 277), Candida tropicalis (MTCC184), Aspergillus niger (MCIM 545) and Aspergillus clavatus (MTCC 132). The investigation of antimicrobial screening data revealed that most of the tested compounds are moderate to good microbial inhibitors.

Full text of DOI:10.1016/j.ejmech.2014.06.053

European Journal of Medicinal Chemistry 83 (2014) 490e497
Contents lists available at ScienceDirect
European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Short communication
Synthesis and biological evaluation of novel N-aryl maleimide
derivatives clubbed with
a-hydroxyphosphonates
,
Nilesh S. Patil a, Ganesh B. Deshmukh a, Sambhaji V. Patil a *, Avinash D. Bholay b,
Nitin D. Gaikwad a
a Organic Chemistry Research Centre, Department of Chemistry, K.R.T. Arts, B.H. Commerce and A.M. Science College, Gangapur Road, Nashik 422 002,
MS, India
b Post Graduate Department of Microbiology, K.R.T. Arts, B.H. Commerce and A.M. Science College, Gangapur Road, Nashik 422 002, MS, India
a r t i c l e i n f o
a b s t r a c t
Article history:
A series of novel molecules 5aeg containing N-aryl maleimide and
a
-hydroxyphosphonate moieties
Received 17 February 2014
Received in revised form
24 June 2014
Accepted 25 June 2014
Available online 26 June 2014
were synthesized. A distinct approach for high-yielding synthesis of
a-hydroxyphosphonates has been
discovered using various catalyst and solvents. The structures of the synthesized compounds were
elucidated by IR, NMR, MS and CHN analysis. All the synthesized compounds were tested for qualitative
(Zone of inhibition) and quantitative (MIC) antimicrobial activities against two pathogenic bacteria such
as Bacillus subtilis (NCIM 2250) and Escherichia coli (ATCC 25922) and four pathogenic fungi such as
Candida albicans (MTCC 277), Candida tropicalis (MTCC184), Aspergillus niger (MCIM 545) and Aspergillus
clavatus (MTCC 132). The investigation of antimicrobial screening data revealed that most of the tested
compounds are moderate to good microbial inhibitors.
Keywords:
N-aryl maleimide
a
-hydroxyphosphonate
© 2014 Elsevier Masson SAS. All rights reserved.
Antibacterial
Antifungal activity
Triethylphosphite
1. Introduction
This situation highlights the need to develop new and more
effective antimicrobial drugs [13].
Infectious diseases caused by microbes are more rampant world
wide than during the last century. Scientists are working hard to
find ways that will control theses germs but trying to conquer them
is not an easy task. At the present time, different classes of anti-
bacterial drugs [1e4] such as sulfa drugs, nitrofuranes, penicillins,
cephalosporins, tetracyclines, macrolides and oxazolidinones, and
antifungal drugs [5e10] such as fluconazole, ketoconazole and
miconazole are available. Nevertheless, many of them encounter
diverse limitations. For example, the strong antifungal drug
Amphotericin B suffers from its clinical applications due to its
serious nephrotoxicity [11]. Methicillin-resistant staphylococcus
aureus and multidrug resistant gram-positive bacteria cause
serious problems. Disease causing microbes are very good at
adapting to new environments making it hard to find a way to get
rid of them. Microbes can quickly develop new features that make
them resistant to the drugs that were once able to kill them [12].
Maleimides are emerging as important pharmacophores in
recent times and play a vital role as medicinal agents with a range
of biological activities such as antibacterial [14], analgesic [15],
antistress agents [16], antiprotozoal [17], antiangiogenic [18],
cytotoxic, DNA binding and apoptotic inducing activity [19]. Several
derivatives of maleimides are reported as selective inhibitors of
monoglyceride lipase [20], GSK-3a [21], Cdc25B [22], Bfl-1 [23] and
DNMT-1 [24] etc. Synthesis and biological activity of N-aryl mal-
eimide analogous have been extensively investigated. N-aryl mal-
eimides provide the scaffold for many natural products such as
polycitrin [25], camphorataimides [26], rebeccamycine and staur-
osporine [27]. These compounds exhibit angiogenesis inhibition
[27], protein kinase inhibition [28] and antiproliferative [29]
activities.
S. Zacchino and group have reported the antimicrobial activities
of N-substituted maleimide derivatives against Candida spp. and it
was concluded that the intact maleimide ring is essential for
excellent activities [30]. The maleimide skeleton in naturally
occurring himanimide and their unnatural analogues were found
to exhibit good antimicrobial activities [31]. The maleimide
molecules contain general structure eCOeN(R)eCOe, so they are
* Corresponding author.
E-mail address: sambhajipatil@yahoo.com (S.V. Patil).
http://dx.doi.org/10.1016/j.ejmech.2014.06.053
0223-5234/© 2014 Elsevier Masson SAS. All rights reserved.

N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
491
hydrophobic and neutral, and can therefore penetrate biological
2. Result and discussion
membranes [32]. Sortino and co-workers have demonstrated that,
substituents on 3 and 4 positions in maleimides show variable ef-
fect on activity [33]. These findings encourage us to choose mal-
eimide skeleton for the biological study.
Synthesis of the organophosphorous compounds has recently
attracted much attention [34e39] due to their wide-spread bio-
logical activities. These compounds act as prodrugs and analogues
of natural phosphates [40]. They are reported to possess various
biological activities such as anti bacterial and anti fungal [41e46],
anti HIV [47,48], anticancer [49e53], anti-inflammatory [54], anti-
viral [55e57], antihypertensive [58], antituberculor [59] and bone
seeking agents [60]. Thus, they are shown to be good pharmaco-
phores for the design of bioactive molecules.
2.1. Chemistry
The synthetic route to compounds 5aeg is outlined in Scheme 1.
Derivatives of substituted N-arylmaleimide 1aeg were synthesized
by using our reported procedure [64]. The compounds 2aeg was
prepared by refluxing 1aeg with bromine in CCl4 [65]. 2aeg were
reacted further with N, N-dimethylamine in DMF at 10 ꢀC to afford
3-(dimethylamino)-1-aryl-1H-pyrrole-2,5 dione 3aeg in quantita-
tive yield. The Vilsmeier Haack formylation of 3aeg at 0e5 ꢀC
yielded 4-(dimethylamino)-2,5-dihydro-2,5-dioxo-1-aryl-1-H-pyr-
role-3-carbaldehyde 4aeg in excellent yield.
There are several conventional methods reported in literature
such as Abramov reaction [62,63], Field reaction [66], Pudovik
reaction [67] for the synthesis of phosphonate compounds from
aldehydes/ketones and di/trialkyl phosphite using various bases
such as sodium alkoxide [62,67], triethylamine [66], ethyl mag-
nesium bromide [68], potassium or cesium fluoride [69], LDA
[70], MgO [71] etc or acid catalyst such as BF3Et2O and AlCl3 or
HCl [72], alumina [73], TFA or TfOH [74], Ti(OPri) [75] etc. In most
cases these reactions suffer from the long reaction time or exotic
reaction conditions. In order to find the more efficient reaction
condition for the synthesis of 5a from 4a, we perform the ana-
logues reactions using various catalysts and solvents as depicted
in Table 1. The synthesis of 5a from 4a was attempted by using a
number of catalysts such as FeCl3, CdCl2, NH4VO3, TMSCl,
Amberlite IR etc. and various solvents. The reaction of 4a with
equimolar amount of triethylphosphite using TMSCl as a catalyst
and acetonitrile as a solvent at reflux temperature for 50 min
afforded 5a in 85% yield (Entry-1) while analogues reaction
using toluene as a solvent took 2.0 h to give 5a in 72% yield
(Entry-2). Use of FeCl3, CdCl2, Amberlite IR 400 (Entry-3,4,5) does
not give satisfactory results in terms of both reaction time and
yield.
In view of the high degree of bioactivity shown by both N-aryl
maleimides and phosphonate analogs (Fig. 1, IeV), we have
focused on the design of novel structural entities that incorpo-
rate both of these structural and functional moieties into a single
molecular scaffold (5aeg) to evaluate the potential additive ef-
fects of these two systems on biological activity, especially with
regard to antimicrobial activity. Fig. 1 describes the biological
activities of the various maleimide derivatives and phosphonate
scaffold. Till date, adequate efforts have not been made to
combine N-aryl maleimide and phosphonates as a single mo-
lecular scaffold.
Recently, various methodologies have been developed for the
synthesis of a-hydroxyphosphonates from aldehydes [39,61e63].
We developed new, protocols to synthesize these desired com-
pounds. In the present work, we achieved excellent yields of
desired compounds with just the 5 mol% of the catalyst, with short
reaction time and easy work-up procedures.
We herein report the synthesis of novel N-aryl maleimide de-
rivatives clubbed with phosphonates (Scheme 1) from novel car-
baldehydes using efficient, high yielding catalysts, in aqueous
medium with the aim of investigating their antimicrobial activity.
Fig. 1. Biological activities of the natural*/unnatural Maleimide derivatives and phosphonate scaffold.

492
N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
Scheme 1. Reagent and conditions: (i) Br2, CCl4, Reflux, 1 h; (ii) N, N dimethylamine, DMF, 10 ꢀC, 30 min; (iii) DMF:POCl3, 0e5 ꢀC, 30 min; (iv) P(OEt)3, NH4VO3, Water, Reflux,
20.0 min.
NH4VO3 have been reported as an effective catalyst for the
synthesis of -hydroxyphosphonates [61]. Use of NH4VO3 as a
IR spectrum of the compounds 5aeg showed characteristics
absorption peaks due to OeH, PeC, P]O and PeO (Table 4). 1H
NMR spectra of the compounds 5a, 5c showed multiplet centered
at 5.31 due to (CHeP) proton due to coupling with OeH proton
while compounds 5b, 5d to 5g showed doublet due to (CHeP)
a
catalyst and acetonitrile as a solvent at reflux condition afforded
89% yield of the desire compound in 40 min while analogues re-
action using water as a solvent in contrast to previous reports [61]
give almost quantitative yield (98%) of the 5a in only 20 min. With
optimized reaction conditions, further derivatives 5beg was syn-
thesized and characterized by spectral and analytical methods.
proton with 1H resonance in the range of
d 5.26e5.45 ppm in which
OeH proton coupling was not observed. 13C NMR spectrum showed
1
doublet in the range of 64.4e65.1 ppm with JP-C in the range of
163.2e168.2 Hz.
The 13C spectrum of the compounds 3c, 4c and 5c containing
2.2. Spectroscopic analysis
flurosubstituted benzene showed doublet for ipso (C1eF, 1JF-C in the
2
range of 246.15e243.82 Hz), ortho (C2eF, JF-C in the range of
IR spectrum of the compounds 3aeg showed stretching fre-
quencies in the range of 1751e1757 cmꢁ1 and 1691e1710 cmꢁ1
attributed to carbonyl groups (Table 2). The 1H NMR peaks at
4.94e4.99 ppm are due to olefinic proton (CH¼). The appearance of
the aldehydic group in compound 4aeg was confirmed by IR spec-
trum (Table 3); 1H NMR spectrum showed the aldehydic proton
singlet in the range of 9.78e9.81 ppm and 13C NMR spectrum
showed aldehydic carbonyl carbon in the range of 182.1e182.4 ppm.
22.87e22.83 Hz) and meta (C3eF, 1JF-C in the range of 9.15e9.14 Hz)
carbons to the fluorine due to C to F one bond, two bond and three
bond couplings respectively.
The CF3 carbon in the compounds 3d, 4d and 5d appeared as a
quartet in the range of 123.4e123.7 ppm (1JF-C in the range of
271.20e270.15 Hz). The
a-carbon to the CF3 also appeared as
quartet (2JF-C in the range of 35.47e33.22 Hz) and
range of 131.2e131.1 ppm.
d value in the
Table 1
2.3. Antimicrobial activity
Effect of various catalyst and solvent condition on the synthesis of
a-hydrox-
yphosphonate from 4a.
The himanimide C (Fig. 1, I) exhibited antifungal activity against
Alternaria porri, Aspergillus ochraceus and Pythium irregulare from
concentration 25
mg/mL on. It also showed moderate or weak
antibacterial activity [31]. The N-aryl substituted maleimides re-
ported as fungicidal against many antifungal strains with no clear
influence of the different substituents on the benzene ring [33]. The
phosphonates coupled with tetrazolo [1,5-a] quinoline derivatives
Table 2
Entry Catalysta
Solvent
Temperature o
C
Time
Yieldb
%
M.P., yield and IR of the compounds (3aeg).
Entry
R1
R2
R3
M.P. (ꢀC)
Yielda (%)
(KBr, nmax/cmꢁ1
C]O
)
1
2
3
4
5
6
7
TMSCl
TMSCl
FeCl3
Acetonitrile Reflux
50 min 85
Toluene Reflux
Acetonitrile Reflux
Toluene Reflux
2.0 h
18 h
4.0 h
3.5 h
72
18
26
30
CdCl2
3a
3b
3c
3d
3e
3f
H
Br
F
H
Cl
H
H
H
H
H
CF3
H
H
H
H
H
H
H
Cl
142e144
144e146
148e150
70e72
136e138
112e114
86e88
98
96
96
94
96
98
96
1753, 1691
1757, 1691
1757, 1704
1751, 1701
1751, 1693
1755, 1710
1753, 1706
Amberlite IR 400 Acetonitrile Reflux
NH4VO3
NH4VO3
Acetonitrile Reflux
Water Reflux
40 min 89
20 min 98
a
4a (1 mmol) was treated with Triethylphosphite (1 mmol) in the presence of the
Cl
H
catalyst 5 mol % (except entry 1and 2, where equivalent amount of TMSCl were
used).
3g
b
a
Yield refers to isolated yield.
Yield refers to isolated yield.

N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
493
Table 3
respectively against C. albicans. Excellent MIC's were observed
against Candida tropicalis for each of the compounds 5b, 5c
M.P., yield and IR of the compounds (4aeg).
Entry
R1
R2
R3
M.P. (ꢀC)
Yielda (%)
(KBr, nmax/cmꢁ1
)
required 15
Aspergillus niger moderate activity were observed with MIC of
15 g/mL for each of the 5c, 5d and 5g. In case of Aspergillus clavatus
compounds, 5c and 5d exhibited good activity which required
10 g/mL and compound 5g required 15 g/mL.
From the data, it is clear that antimicrobial activity of the
mg/mL, and for 5d, 5f required 10 mg/mL. Against
C]O
CHO
m
4a
4b
4c
4d
4e
4f
H
Br
F
H
Cl
H
H
H
H
H
CF3
H
H
H
H
H
H
H
Cl
166e168
186e188
164e166
110e112
172e174
162e164
90e92
84
83
81
78
83
84
81
1757, 1708
1762, 1706
1758, 1704
1760, 1706
1764, 1704
1758, 1704
1762, 1708
2866, 1656
2868, 1664
2874, 1662
2871, 1676
2870, 1660
2850, 1664
2860, 1662
m
m
compounds 5aeg is influenced by changing the substituents on the
aromatic ring. Among compounds 5b, 5c and 5e with Br, F, Cl
respectively on 4-position of the aromatic ring, 5c was consistently
excellent with respect to the standard antibiotics used; 5b showed
better activity than 5e. Substituent at 3-position of the aromatic
ring in 5d and 5f showed good activity. 5a with no substituent on
aromatic ring showed the least activity among synthesized
compounds.
Cl
H
4g
a
Yield refers to isolated yield.
Table 4
M.P., yield and IR of the compounds (5aeg), using NH4VO3, water.
Entry R1 R2 R3 M.P.( ꢀC) Yielda (KBr, nmax/cmꢁ1
)
(%)
OeH C]O
PeC P]O PeO
3. Conclusion
5a
5b
5c
5d
5e
5f
H
Br
F
H
Cl
H
H
H
H
H
CF3
H
H
H
H
H
H
H
170e172 98
136e138 96
158e160 94
118e120 95
160e162 96
138e140 97
3267 1751, 1689 1400 1207 1054
3226 1753, 1693 1392 1211 1053
3245 1747, 1691 1396 1226 1054
3190 1755, 1704 1386 1197 1053
3249 1749, 1691 1394 1211 1054
3259 1753, 1691 1396 1207 1053
3244 1755, 1699 1396 1209 1060
A series of novel N-aryl maleimide derivatives clubbed with
aehydroxy phosphonates 5aeg were successfully synthesized us-
ing readily available catalyst, water as the green solvent, with high
yield, short duration and avoidance of tedious work-up procedure.
The pharmacological studies were undertaken to evaluate the ef-
fect of substituents for their antimicrobial activities against two
pathogenic bacteria and four pathogenic fungi. Most of the syn-
thesized compounds exhibited moderate to good activity towards
Gram-positive and Gram-negative bacteria as well as all of the
fungal species. The enhancement in antibacterial and antifungal
activity can be attributed to the presence of pharmacologically
active F, Cl, Br, CF3 substituents, irrespective of their position in the
molecule. The present study promises to be very useful to get lead
antimicrobial agents.
Cl
H
5g
Cl 106e108 95
a
Yield refers to isolated yield.
[41] and aziridine derivatives [43] showed significant antimicrobial
activity.
Results of antimicrobial screening revealed that of the com-
pounds tested 4aeg and 5aeg, the phosphonates 5aeg showed
moderate to good activity while 4aeg showed very low or no sig-
nificant activity compared to reference antibiotics. As shown in
Table 5, most of the compounds were active against Gram positive
and Gram negative bacteria as well as all of the fungal species.
Careful analysis of the primary screening (zone of inhibition) and
MICs in Tables 5 and 6 provides some lead molecules with p-F, m-
CF3 and m-Cl substituents on the phenyl ring showed good anti-
bacterial and antifungal activity against most of the tested patho-
gens; they inhibited the Gram negative and Gram positive
pathogens equally and antifungal species with MIC value in be-
4. Experimental section
Melting points are uncorrected. The 1H (300 MHz) and 13C
(75 MHz) NMR spectra were recorded on a Varian NMR Mercury
300 spectrometer. Chemical shifts were reported in ppm relative to
tetramethylsilane (TMS), and multiplicities are given as s (singlet),
brs (broad singlet), d (doublet), t (triplet), q (quartet), or m
(multiplet). Infrared spectra were recorded as KBr pellets on a
Shimadzu FTIR-408 spectrophotometer. Mass spectra were recor-
ded on a Shimadzu LC-MS: EI QP 2010A mass spectrometer with an
ionization potential of 70 eV. Elemental analyses (C, H and N) were
performed on Thermo Finnigan Eager 300 EA 1112 series analyzer.
tween 10 and 25
Against B. subtilis, both 5c and 5f required 10
5c and 5d showed better activity and required 10
compound 5g required 15 g/mL against Escherichia coli. For anti-
mg/mL.
mg/mL. Compound
m
g/mL while
m
fungal strains compounds 5c, 5f required 15 and 10
mg/mL
Table 5
Antimicrobial screening of synthesized compounds 5aeg (zone diameter of growth inhibition in mm).
Entry
Bacillus subtilis
Escherichia coli
Candida albicans
Candida tropicalis
Aspergillus niger
Aspergillus clavatus
NCIM 2250
ATCC 25922
MTCC 277
MTCC 184
MCIM 545
MTCC 1323
5a
5b
5c
5d
5e
5f
5g
Strept.
Gris.
13.4
15.1
15.6
15.4
e
13.2
13.1
15.8
15.7
13.4
13.5
15.4
16.4
n.t.
e
16.1
16.8
16.7
17.2
15.9
17.1
16.2
n.t.
e
16.3
16.4
17.3
17.4
e
13.8
16.5
15.2
e
15.5
16.4
16.6
15.8
13.6
16.6
n.t.
15.8
13.6
16.2
n.t.
16.6
15.1
n.t.
16.2
16.8
n.t.
16.8
17.3
16.9
17.6
Bold values indicates better results.
n.t. not tested.
Strept. : Streptomycine (100
Gris. : Griseofulvin (100 g/disc).
g/disc).
mg/disc).
m
Test Compound: (100
m
(ꢁ): Inactive.

494
N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
Table 6
Antimicrobial screening of synthesized compounds 5aeg and minimum inhibitory concentration (MIC) in mg/mL.
Entry
Bacillus subtilis
Escherichia coli
Candida albicans
Candida tropicalis
Aspergillus niger
Aspergillus clavatus
NCIM 2250
ATCC 25922
MTCC 277
MTCC 184
MCIM 545
MTCC 1323
5a
5b
5c
5d
5e
5f
5g
Strept.
Gris.
25
20
10
15
e
20
25
10
10
25
20
15
05
n.t.
e
20
15
15
10
25
10
20
n.t.
05
e
20
20
10
10
e
25
15
20
e
20
15
15
20
25
15
n.t.
05
10
20
05
n.t.
10
20
n.t.
05
20
15
n.t.
05
Bold values indicates better results.
n.t. not tested.
Strept. : Streptomycine (
Gris. : Griseofulvin ( g/mL).
g/mL).
mg/mL).
m
Test compound: (
m
(ꢁ): Inactive.
Reactions were monitored by thin layer chromatography (TLC),
carried out on 0.2 mm silica gel 60 F254 (Merck) plates using UV
light (254 and 366 nm) for detection and compounds were purified
4.3.2. 1-(4-Bromophenyl)-3-(dimethylamino)-1H-pyrrole-2,5-
dione (3b)
1H NMR (300 MHz, CDCl3):
d
3.21 (brs, 6H, 2 ꢂ CH3, NMe2), 4.94
by column chromatography by using silica gel of 5e20
mm (Merck,
(s, 1H, C]CH), 7.25 (d, 2H, J ¼ 8.7 Hz, AreH), 7.55 (d, 2H, J ¼ 8.7 Hz,
AreH); 13C NMR (75 MHz, CDCl3): 41.0 (CH3, NMe), 41.8 (CH3, NMe),
87.4 (HC¼), 120.5 (AreC), 127.5 (2C's, AreC), 130.9 (AreC), 131.7
(2C's, AreC), 150.2 (NeC¼), 165.1 (C]O), 168.8 (C]O); MS: m/z 295
(Mþ1), 297 (Mþ3); Elemental analysis: C12H11BrN2O2, Calcd.: C:
48.84%; H: 3.76%; N: 9.49%. Found: C: 48.62%; H: 3.61%; N: 9.22%.
60e120 mesh). Column dimension is 39 ꢂ 2 cm2 and elution vol-
ume used is about 200e400 mL for each product where necessary.
Common reagent grade chemicals are commercially available and
were used without further purification.
4.1. General procedure for the synthesis of compound (1aeg)
4.3.3. 3-(Dimethylamino)-1-(4-fluorophenyl)-1H-pyrrole-2,5-
dione (3c)
To a solution of the substituted anilines (0.01 mol) in acetic acid
(10 mL), the maleic anhydride was added. The reaction mixture was
stirred for 10 min. To this suspension, sulfuric acid (0.025 mol) was
added while stirring. The temperature of the reaction mixture was
then maintained at 60 ꢀC for 30e45 min. The cooled reaction
mixture was poured onto crushed ice. The solid separated was
collected, washed with aqueous sodium bicarbonate and then with
water, and recrystallized from aqueous ethanol [64].
1H NMR (300 MHz, CDCl3):
d
3.20 (brs, 6H, 2 ꢂ CH3, NMe2), 4.96
(s, 1H, C]CH), 7.08e7.14 (m, 2H, AreH), 7.28e7.33 (m, 2H, AreH);
13C NMR (75 MHz, CDCl3): 41.2 (CH3, NMe), 41.8 (CH3, NMe), 87.5
(HC¼), 115.7 (d, 2C's, 2JF-C ¼ 22.87 Hz, AreC), 127.9 (AreC), 128.1 (d,
3
1
2C's, JF-C
¼
9.15 Hz, AreC), 150.4 (NeC]), 169.3 (d, JF-
¼ 244.95 Hz, AreC), 165.5 (C]O), 169.4 (C]O); MS: m/z 235
C
(Mþ1); Elemental analysis: C12H11FN2O2, Calcd.: C: 61.53%; H:
4.73%; N: 11.96%. Found: C: 61.28%; H: 4.58%; N: 11.77%.
4.2. General procedure for the synthesis of compound (2aeg)
To a solution of N-arylpyrrolidine-2,5-dione 1aeg (0.01 mol) in
4.3.4. 3-(Dimethylamino)-1-(3-(trifluoromethyl)phenyl)-1H-
pyrrole-2,5-dione (3d)
CCl4 (8 mL) was added dropwise
a
solution of bromine
1H NMR (300 MHz, CDCl3):
d
3.26 (brs, 6H, 2 ꢂ CH3, NMe2), 4.98
(0.011 mmol) in CCl4 (4 mL) at 25 ꢀC and reflux for 1e1.5 h (TLC,
hexane:ethyl acetate, 2:1). White solid separated was then filtered,
washed with cold CCl4 (4e8 mL), dried and recrystallized using
ethanol [65].
(s, 1H, C]CH), 7.56 (s, 3H, AreH), 7.68 (s, 1H, AreH); 13C NMR
(75 MHz, CDCl3): 39.8 (CH3, NMe), 40.7 (CH3, NMe), 87.6 (HC¼),
122.8 (AreC), 123.5 (AreC), 123.7 (q, 1JF-C ¼ 270.15 Hz, AreC), 129.2
2
(2C's, AreC), 131.1 (q, JF-C ¼ 33.22 Hz, AreC), 132.5 (AreC), 150.3
(NeC¼), 165.2 (C]O), 168.8 (C]O); MS: m/z 285 (Mþ1); Elemental
analysis: C13H11F3N2O2, Calcd.: C: 54.93%; H: 3.90%; N: 9.86%.
Found: C: 54.71%; H: 3.77%; N: 9.62%.
4.3. General procedure for the synthesis of compound (3aeg)
To a solution of trans-3,4-dibromo-1-arylpyrrolidine-2,5-dione
2 (0.01 mol) in DMF (10 mL) N,N-dimethylamine (0.03 mol) was
added dropwise at 10 ꢀC and stirred for 30.0 min. The reaction
mixture was poured over crushed ice. The golden yellow solid
separated out was filtered and recrystallized from aqueous ethanol.
4.3.5. 1-(4-Chlorophenyl)-3-(dimethylamino)-1H-pyrrole-2,5-
dione (3e)
1H NMR (300 MHz, CDCl3):
(s, 1H, C]CH), 7.28e7.46 (m, 4H, AreH); MS: m/z 251 (Mþ1), 253
(Mþ3); Elemental analysis: C12H11ClN2O2, Calcd.: C: 57.49%; H:
4.42%; N: 11.17%. Found: C: 57.37%; H: 4.58%; N: 11.39%.
d
3.24 (brs, 6H, 2 ꢂ CH3, NMe2), 4.96
4.3.1. 3-(Dimethylamino)-1-phenyl-1H-pyrrole-2,5-dione (3a)
1H NMR (300 MHz, CDCl3):
d
3.22 (brs, 6H, 2 ꢂ CH3, NMe2), 4.95
(s, 1H, C]CH), 7.33e7.43 (m, 5H, AreH); 13C NMR (75 MHz, CDCl3):
41.0 (CH3, NMe), 41.9 (CH3, NMe), 87.4 (HC¼), 126.2 (2C's, AreC),
127.1 (AreC), 128.2 (2C's, AreC), 131.8 (AreC), 150.3 (NeC¼), 165.5
(C]O), 169.4 (C]O); MS: (m/z) 217 (Mþ1); Elemental analysis:
4.3.6. 1-(3-Chlorophenyl)-3-(dimethylamino)-1H-pyrrole-2,5-
dione (3f)
1H NMR (300 MHz, CDCl3):
(s, 1H, C]CH), 7.25e7.39 (m, 4H, AreH); MS: m/z 251 (Mþ1), 253
(Mþ3); Elemental analysis: C12H11ClN2O2, Calcd.: C: 57.49%; H:
4.42%; N: 11.17%. Found: C: 57.37%; H: 4.13%; N: 11.23%.
d
3.21 (brs, 6H, 2 ꢂ CH3, NMe2), 4.97
C
12H12N2O2, Calcd.: C: 66.65%; H: 5.59%; N: 12.96%. Found: C:
66.32%; H: 5.41%; N: 12.75%.

N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
495
4.3.7. 1-(2-Chlorophenyl)-3-(dimethylamino)-1H-pyrrole-2,5-
dione (3g)
1H, CHO); MS: m/z 279 (Mþ1), 281 (Mþ3); Elemental analysis:
C13H11ClN2O3, Calcd.: C: 56.03%; H: 3.98%; N: 10.05%. Found: C:
56.27%; H: 4.23%; N: 10.32%.
1H NMR (300 MHz, CDCl3):
d
3.26 (brs, 6H, 2 ꢂ CH3, NMe2), 4.99
(s, 1H, C]CH), 7.24e7.28 (m, 1H, AreH), 7.32e7.38 (m, 2H, AreH),
7.49e7.52 (m, 1H, AreH); MS: m/z 251 (Mþ1), 253 (Mþ3);
Elemental analysis: C12H11ClN2O2, Calcd.: C, 57.49%; H, 4.42%; N,
11.17%. Found: C, 57.32%; H, 4.21%; N, 11.04%.
4.4.6. 1-(3-Chlorophenyl)-4-(dimethylamino)-2,5-dihydro-2,5-
dioxo-1H-pyrrole-3-carbaldehyde (4f)
1H NMR (300 MHz, CDCl3):
d
3.69 (s, 6H, 2 ꢂ CH3, NMe2),
7.26e7.29 (m, 1H, AreH), 7.34e7.41 (m, 3H, AreH), 9.81 (s, 1H,
CHO); MS: m/z 279 (Mþ1), 281 (Mþ3); Elemental analysis:
4.4. General procedure for the synthesis of compound (4aeg)
C
13H11ClN2O3, Calcd.: C: 56.03%; H: 3.98%; N: 10.05%. Found: C:
To a Vilsmeier Haack adduct prepared from DMF (0.012 mol)
and POCl3 (0.05 mol) at 0 ꢀC was added solution of 4aeg (0.01 mol)
in 2 mL DMF, reaction mixture was then stirred at 0e5 ꢀC for
30 min. The reaction mixture was poured into cold water. The
yellow product separated on neutralization with aqueous NaHCO3
was filtered, washed with cold water, dried and purified by column
chromatography (Hexane:Ethyl Acetate, 6:4).
56.33%; H: 4.22%; N: 10.32%.
4.4.7. 1-(2-Chlorophenyl)-4-(dimethylamino)-2,5-dihydro-2,5-
dioxo-1H-pyrrole-3-carbaldehyde (4g)
1H NMR (300 MHz, CDCl3):
d
3.67 (s, 6H, 2 ꢂ CH3, NMe2),
7.20e7.35 (m, 1H, AreH), 7.22e7.44 (m, 2H, AreH), 7.50e7.61 (m,
1H, AreH), 9.80 (s, 1H, CHO); MS: m/z 279 (Mþ1), 281 (Mþ3);
Elemental analysis: C13H11ClN2O3, Calcd.: C: 56.03%; H: 3.98%; N:
10.05%. Found: C: 56.29%; H: 4.19%; N: 10.19%.
4.4.1. 4-Dimethylamino)-2,5-dihydro-2,5-dioxo-1-phenyl-1H-
pyrrole-3-carbaldehyde (4a)
1H NMR (300 MHz, CDCl3):
d
3.62 (s, 6H, 2 ꢂ CH3, NMe2),
4.5. General procedure for the synthesis of compound (5aeg)
7.32e7.45 (m, 5H, AreH), 9.78 (s, 1H, CHO); 13C NMR (75 MHz,
CDCl3): 42.5 (CH3, NMe), 48.3 (CH3, NMe), 98.0 (HC¼), 126.3 (2C's,
AreC),127.9 (AreC), 128.8 (2C's, AreC), 130.9 (AreC), 149.4 (NeC¼),
163.3 (C]O), 169.4 (C]O), 182.1 (CHO); MS: m/z 245 (Mþ1);
Elemental analysis: C13H12N2O3, Calcd.: C: 63.93%; H: 4.95%; N:
11.47%. Found: C: 63.71%; H: 4.67%; N: 11.37%.
To a suspension of 4aeg (0.01 mol) in water (5 mL), catalyst
NH4VO3 (5 mol %) was added. The suspension was heated
(50e60 ꢀC) under stirring and then triethylphosphite (0.01 mol)
was added slowly, and refluxed for 20 min. The suspension turns
into clear solution, followed by separation of yellow solid. It was
filtered, dried and purified by using column chromatography (Ethyl
acetate : Hexane, 6:4).
4.4.2. 1-(4-Bromophenyl)-4-(dimethylamino)-2,5-dihydro-2,5-
dioxo-1H-pyrrole-3-carbaldehyde (4b)
1H NMR (300 MHz, CDCl3):
d
3.62 (s, 6H, 2 ꢂ CH3, NMe2), 7.26 (d,
4.5.1. Diethyl (4-(dimethylamino)-2,5-dihydro-2,5-dioxo-1-phenyl-
1H-pyrrol-3-yl)(hydroxy)methylphosphonate (5a)
2H, J ¼ 9.60 Hz, AreH), 7.59 (d, 2H, J ¼ 9.60 Hz, AreH), 9.79 (s, 1H,
CHO); 13C NMR (75 MHz, CDCl3): 42.7 (CH3, NMe), 48.5 (CH3, NMe),
98.2 (HC¼), 121.7 (AreC), 127.8 (2C's, AreC), 130.0 (AreC), 132.1
(2C's, AreC), 149.4 (NeC¼), 163.1 (C]O), 169.1 (C]O), 182.2 (CHO);
MS: m/z 323 (Mþ1), 325 (Mþ3); Elemental analysis: C13H11BrN2O3,
Calcd.: C: 48.32%; H: 3.43%; N: 8.67%. Found: C: 48.22%; H: 3.28%;
N: 8.51%.
1H NMR (300 MHz, CDCl3):
d
1.30e1.37 (m, 6H, 2 ꢂ CH3), 3.43 (s,
3
6H, NMe2), 4.15e4.26 (m, 4H, 2 ꢂ OCH2), 5.01 (d, 1H, JHC-
¼ 9.6 Hz, OH), 5.26 (dd, 1H, 2JP-CH ¼ 10.2 Hz and 3JHC-OH ¼ 9.6 Hz,
OH
PeCHeO), 7.25e7.34 (m, 3H, AreH), 7.40e7.45 (m, 2H, AreH); 13C
NMR (75 MHz, CDCl3): 16.4 (2C's, CH3), 43.1 (2C's, NMe2), 63.0 (d,
2JP-O-C ¼ 8.02 Hz, PeOeCH2), 63.4 (d, 2JP-O-C ¼ 8.02 Hz, PeOeCH2),
65.0 (d, 1JP-C ¼ 167.10 Hz, PeCHeO), 93.9 (HC ¼ ), 126.1 (2C's, AreC),
127.5 (AreC), 128.8 (2C's, AreC), 131.2 (AreC), 145.3 (¼CeN), 165.0
(C]O), 171.4 (C]O); MS: m/z 383 (Mþ1), 381 (Mꢁ1); Elemental
analysis: C17H23N2O6P, Calcd.: C: 53.40%; H: 6.06%; N: 7.33%. Found:
C: 53.24%; H: 5.86%; N: 7.03%.
4.4.3. 4-(Dimethylamino)-1-(4-fluorophenyl)-2,5-dihydro-2,5-
dioxo-1H-pyrrole-3-carbaldehyde (4c)
1H NMR (300 MHz, CDCl3):
d
3.68 (s, 6H, 2 ꢂ CH3, NMe2),
7.13e7.18 (m, 2H, AreH), 7.30e7.35 (m, 2H, AreH), 9.80 (s, 1H,
CHO); 13C NMR (75 MHz, CDCl3): 42.7 (CH3, NMe), 48.6 (CH3, NMe),
2
98.2 (HC¼), 116.0 (d, 2C's, JF-C ¼ 22.87 Hz, AreC), 126.9 (AreC),
4.5.2. Diethyl (1-(4-bromophenyl)-4-(dimethylamino)-2,5-
dihydro-2,5-dioxo-1H-pyrrol-3-yl)(hydroxy)methylphosphonate
(5b)
3
1
128.3 (d, 2C's, JF-C ¼ 9.14 Hz, AreC), 149.5 (NeC¼), 161.9 (d, JF-
¼ 243.82 Hz, AreC), 163.5 (C]O), 169.4 (C]O), 182.4 (CHO); MS:
C
m/z 263 (Mþ1); Elemental analysis: C13H11FN2O3, Calcd.: C: 59.54%;
1H NMR (300 MHz, CDCl3):
d
1.31e1.43 (m, 6H, 2 ꢂ CH3), 3.44 (s,
H: 4.23%; N: 10.68%. Found: C: 59.44%; H: 4.42%; N: 10.46%.
6H, NMe2), 4.17e4.27 (m, 4H, 2 ꢂ OCH2), 4.95 (brs, 1H, OH), 5.26 (d,
1H, 2JP-CH ¼ 13.2 Hz, PeCHeO), 7.24 (d, 2H, J ¼ 8.7 Hz, AreH), 7.55
(d, 2H, J ¼ 8.7 Hz, AreH); 13C NMR (75 MHz, CDCl3): 16.4 (2C's, CH3),
43.2 (2C's, NMe2), 63.1 (d, 2JP-O-C ¼ 8.02 Hz, PeOeCH2), 63.5 (d, 2JP-
4.4.4. 4-(Dimethylamino)-1-(3-(trifluoromethyl)phenyl)-2,5-
dihydro-2,5-dioxo-1H-pyrrole-3-carbaldehyde (4d)
1H NMR (300 MHz, CDCl3):
d
3.67 (s, 6H, 2 ꢂ CH3, NMe2),
¼ 8.02 Hz, PeOeCH2), 65.1 (d, 1JP-C ¼ 167.10 Hz, PeCHeO), 94.2
O-C
7.58e7.68 (m, 4H, AreH), 9.81 (s, 1H, CHO); 13C NMR (75 MHz,
CDCl3): 42.7 (CH3, NMe), 48.5 (CH3, NMe), 98.1 (HC¼), 123.1 (AreC),
(HC¼), 121.2 (AreC), 127.5 (2C's, AreC), 128.0 (AreC), 132.0 (2C's,
AreC), 145.5 (¼CeN), 164.7 (C]O), 170.9 (C]O); MS: m/z 461
(Mþ1), 463 (Mþ3); Elemental analysis: C17H22BrN2O6P, Calcd.: C:
44.27%; H: 4.81%; N: 6.07%. Found: C: 44.40%; H: 4.56%; N: 6.33%
1
123.4 (q, JF-C ¼ 271.20 Hz, CF3), 124.5 (AreC), 129.5 (2C's, AreC),
131.1 (q, 2JF-C ¼ 35.47 Hz, AreC), 131.6 (AreC), 149.2 (NeC¼), 163.0
(C]O), 168.9 (C]O), 182.1 (CHO); MS: m/z 313 (Mþ1); Elemental
analysis: C14H11F3N2O3, Calcd.: C: 53.85%; H: 3.55%; N: 8.97%.
Found: C: 53.61%; H: 3.32%; N: 8.68%.
4.5.3. Diethyl (4-(dimethylamino)-1-(4-fluorophenyl)-2,5-dihydro-
2,5-dioxo-1H-pyrrol-3-yl)(hydroxy)methylphosphonate (5c)
1H NMR (300 MHz, CDCl3):
d
1.28e1.37 (m, 6H, 2 ꢂ CH3), 3.41
3
4.4.5. 1-(4-Chlorophenyl)-4-(dimethylamino)-2,5-dihydro-2,5-
(s, 6H, NMe2), 4.16e4.25 (m, 4H, 2 ꢂ OCH2), 4.95 (d, 1H, JHC-
dioxo-1H-pyrrole-3-carbaldehyde (4e)
¼ 9.6 Hz, OH), 5.26 (dd, 1H, 2JP-CH ¼ 9.0 Hz and 3JHC-OH ¼ 9.6 Hz
OH
1H NMR (300 MHz, CDCl3):
d
3.73 (s, 6H, 2 ꢂ CH3, NMe2), 7.31
PeCHeO), 7.09e7.14 (m, 2H, AreH), 7.25e7.29 (m, 2H, AreH); 13C
(dd, 2H, J ¼ 8.7 Hz, AreH), 7.43 (dd, 2H, J ¼ 8.7 Hz, AreH), 9.80 (s,
NMR (75 MHz, CDCl3): 16.3 (2C's, CH3), 43.0 (2C's, NMe2), 62.9

496
N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
2
2
(d, JP-O-C ¼ 6.90 Hz, PeOeCH2), 63.3 (d, JP-O-C ¼ 8.02 Hz,
PeOeCH2), 64.4 (d, 1JP-C ¼ 163.2 Hz, PeCHeO), 94.0 (HC¼), 115.6 (d,
conditions. The zone of inhibition was determined from the
diameter of the zone of inhibition using caliper. Each inhibition
zone was measured three times to get average value. The minimum
inhibitory concentration (MIC) values were determined on MH agar
plates by pouring the molted agar in Petri dishes according to Na-
tional Committee for Clinical Laboratory Standards (NCCLS, M7-A5
January 2000), containing the following concentrations (mg/mL):
0 (control), 3, 5,10,15, 20, 30, 40. The MIC was defined as the lowest
concentration tested samples showing no visible bacterial growth
after 24 h incubation period at 37 ꢀC.
2
3
2C's, JF-C ¼ 22.87 Hz, AreC), 127.1 (AreC), 127.8 (d, 2C's, JF-
¼ 9.15 Hz, AreC), 145.5 (¼CeN), 161.3 (d, 1JF-C ¼ 246.15 Hz, AreC),
C
165.0 (C]O), 171.0 (C]O); MS: m/z 401 (Mþ1), 399 (Mꢁ1);
Elemental analysis: C17H22FN2O6P, Calcd.: C: 51.00%; H: 5.54%; N:
7.00%. Found: C: 51.28%; H: 5.31%; N: 7.22%.
4.5.4. Diethyl (4-(dimethylamino)-1-(3-(trifluoromethyl)phenyl)-
2,5-dihydro-2,5-dioxo-1H-pyrrol-3-yl)(hydroxy)
methylphosphonate (5d)
1H NMR (300 MHz, CDCl3):
d
1.32e1.44 (m, 6H, 2 ꢂ CH3), 3.46 (s,
Acknowledgments
6H, NMe2), 4.12e4.27 (m, 4H, 2 ꢂ OCH2), 4.98 (brs, 1H, OH), 5.31 (d,
1H, 2JP-CH ¼ 14.4 Hz, PeCHeO), 7.31e7.66 (m, 4H, AreH); 13C NMR
N.S.P. thanks CSIR, New Delhi for the award of Senior Research
Fellowship [File no. 08/541 (003)/2011-EMR-I]. S.V.P. thanks UGC,
New Delhi for financial support [File no.38-809/2011 (SR)]. We
thank General Secretary and authorities, MVP Samaj, KTHM Col-
lege, Nashik and Dr. V. Balasubramaniyan for his constant
encouragement.
2
(75 MHz, CDCl3): 16.3 (2C's, CH3), 43.1 (2C's, NMe2), 62.9 (d, JP-O-
¼ 6.90 Hz, PeOeCH2), 63.4 (d, 2JP-O-C ¼ 6.90 Hz, PeOeCH2), 64.4
C
(d, 1JP-C ¼ 168.3 Hz, PeCHeO), 94.3 (HC ¼ ), 122.7 (AreC), 123.5 (q,
1JF-C ¼ 270.15 Hz, CF3), 123.9 (AreC), 129.0 (AreC), 129.3 (AreC),
131.2 (q, 2JF-C ¼ 33.22 Hz, AreC), 131.9 (AreC), 145.5 (¼CeN), 164.7
(C]O), 170.5 (C]O); MS: m/z 451 (Mþ1), 449 (Mꢁ1); Elemental
analysis: C18H22F3N2O6P, Calcd.: C: 48.01%; H: 4.92%; N: 6.22%.
Found: C: 48.29%; H: 4.71%; N: 6.47%.
Appendix A. Supplementary data
Supplementary data associated with this article can be found in
the online version, at http://dx.doi.org/10.1016/j.ejmech.2014.06.
053. These data include MOL files and InChiKeys of the most
important compounds described in this article.
4.5.5. Diethyl (1-(4-chlorophenyl)-4-(dimethylamino)-2,5-dihydro-
2,5-dioxo-1H-pyrrol-3-yl)(hydroxy)methylphosphonate (5e)
1H NMR (300 MHz, CDCl3):
d
1.31e1.43 (m, 6H, 2 ꢂ CH3), 3.48 (s,
6H, NMe2), 4.21e4.24 (m, 4H, 2 ꢂ OCH2), 5.03 (brs, 1H, OH), 5.27 (d,
1H, 2JP-CH ¼ 13.2 Hz, PeCHeO), 7.28 (d, 2H, J ¼ 7.8 Hz, AreH), 7.40
(d, 2H, J ¼ 7.8 Hz, AreH); MS: m/z 417 (Mþ1), 419 (Mþ3); Elemental
analysis: C17H22ClN2O6P, Calcd.: C: 48.99%; H: 5.32%; N: 6.72%.
Found: C: 48.71%; H: 5.04%; N: 6.58%.
References
[1] T. Saga, K. Yamaguchi, JMAJ 52 (2009) 103e108.
[2] H.C. Neu, Int. J. Antimicrob. Agents 1 (1991) 47e50.
[3] P.C. Appelbaum, P.A. Hunter, Int. J. Antimicrob. Agents 16 (2000) 5e15.
[4] S.J. Brickner, D.K. Hutchinson, M.R. Barbachyn, P.R. Manninem, D.A. Ulanowicz,
S.A. Garmon, K.C. Grega, S.K. Hendges, D.S. Toops, C.W. Ford, G.E. Zurenko,
J. Med. Chem. 39 (1996) 673e679.
[5] M.K. Kathiravan, A.B. Salake, A.S. Chothe, P.B. Dudhe, R.P. Watode, M.S. Mukta,
S. Gadhwe, Bioorg. Med. Chem. 20 (2012) 5678e5698.
[6] V.T. Andriole, Int. J. Antimicrob. Agents 16 (2000) 317e321.
[7] G. Petrikkos, A. Skiada, Int. J. Antimicrob. Agents 30 (2007) 108e117.
[8] Y.M. Clayton, Proc. R. Soc. Med. 70 (1977) 15e18.
[9] A. Butts, D.J. Krysan, Plos Pathog. 8 (2012) 1e3.
4.5.6. Diethyl (1-(3-chlorophenyl)-4-(dimethylamino)-2,5-dihydro-
2,5-dioxo-1H-pyrrol-3-yl)(hydroxy)methylphosphonate (5f)
1H NMR (300 MHz, CDCl3):
d
1.25e1.40 (m, 6H, 2 ꢂ CH3), 3.44 (s,
6H, NMe2), 4.15e4.31 (m, 4H, 2 ꢂ OCH2), 5.02 (brs, 1H, OH), 5.27 (d,
2
1H, JP-CH ¼ 14.4 Hz, PeCHeO), 7.25e7.37 (m, 4H, AreH); MS: m/z
MS: m/z 415 (Mꢁ1), 417 (Mþ1), 419 (Mþ3); Elemental analysis:
C
17H22ClN2O6P, Calcd.: C: 48.99%; H: 5.32%; N: 6.72%. Found: C:
[10] V. Sharma, R. Bhatiya, Int. J. Res. Pharma. Biomed. 2 (2011) 417e427.
[11] T.H. Grasela, S.D. Goodwin, M.K. Walawander, R.L. Cramer, D.W. Fuhs,
V.P. Moriarty, Pharmacotherapy 10 (1990) 341e348.
[12] M. Sojakova, D. Liptajova, M. Borovsky, J. Subik, Mycopathologia 157 (2004)
163e169.
[13] R.C. Moellering, Int. J. Antimicrob. Agents 37 (2011) 2e9.
[14] S.N. Lopez, M. Sortino, A. Escalante, F. Campos, R. Correa, V. Cechinel Filho,
R.J. Nunes, S.A. Zacchino, Arzneim-Forsch. Drug. Res. 53 (2003) 280e288.
Chem. Abstr. 139 (2003) 292210.
[15] F. Mahle, T. Guimaraes, A. Meira, R. Correa, R. Cruz, R. Nunes, V. Cechinel-Filho,
F. Campos-Buzzi, Eur. J. Med. Chem. 45 (2010) 4761e4768.
[16] R. Badru, P. Anand, B. Singh, Eur. J. Med. Chem. 48 (2012) 81e91.
[17] Y. Durust, H. Karakus, M. Kaiser, D. Tasdemir, Eur. J. Med. Chem. 48 (2012)
296e304.
48.76%; H: 5.11%; N: 6.47%.
4.5.7. Diethyl (1-(2-chlorophenyl)-4-(dimethylamino)-2,5-dihydro-
2,5-dioxo-1H-pyrrol-3-yl)(hydroxy)methylphosphonate (5g)
1H NMR (300 MHz, CDCl3):
d
1.24e1.41 (m, 6H, 2 ꢂ CH3), 3.58 (s,
6H, NMe2), 4.02e4.21 (m, 4H, 2 ꢂ OCH2), 4.93 (brs, 1H, OH), 5.43 (d,
1H, 2JP-CH ¼ 13.2 Hz, PeCHeO), 7.28e7.46 (m, 4H, AreH); MS: m/z
417 (Mþ1), 419 (Mþ3); Elemental analysis: C17H22ClN2O6P, Calcd.:
C: 48.99%; H: 5.32%; N: 6.72%. Found: C: 48.81%; H: 5.17%; N: 6.61%.
4.6. Antimicrobial assay
[18] N. Acero, M.F. Brana, L. Anorbe, G. Dominguez, D. Munoz-Mingarro, F. Mitjans,
J. Piulats, Eur. J. Med. Chem. 48 (2012) 108e113.
The antimicrobial activity of the synthesized compounds was
evaluated by the agar cup plate method. The antibacterial and
antifungal assays were performed in MullereHinton broth and
Czapek Dox broth respectively. Evaluation was performed using the
bacteria reseeded in broth for 24 h at 37 ꢀC, and the fungi were
reseeded in broth for 48 h at 25 ꢀC. The antibacterial activity of
tested samples was studied against one Gram positive bacteria
Bacillus subtilis NCIM 2250, one Gram negative bacteria Escherichia
coli ATCC 25922 while Candida albicans MTCC 277, C. tropicalis
MTCC 184, A. niger MCIM 545 and A. clavatus MTCC 1323 were used
as standard fungal strain. The compounds were diluted in DMF
with required concentration for bioassay. DMF was also loaded as
control. Streptomycin and griseofluvin were used as standards to
evaluate the potency of the tested compounds under the same
[19] Alaa A.-M. Abdel-Aziz, Eur. J. Med. Chem. 42 (2007) 614e626.
[20] N. Matuszak, G. Muccioli, G. Laber, D. Lambert, J. Med. Chem. 52 (2009)
7410e7420.
[21] P. Sivaprakasam, A. Xie, R. Doerksen, Bioorg. Med. Chem. 14 (2006)
8210e8218.
[22] H. Chen, Y. Liu, L. Wang, Q. Shen, J. Li, F. Nan, Bioorg. Med. Chem. 20 (2010)
2876e2879.
[23] J.R. Cashman, M. MacDonald, S. Ghirmai, K.J. Okolotowicz, E. Sergienko,
B. Brown, X. Garcia, D. Zhai, R. Dahl, J.C. Reed, Bioorg. Med. Chem. 20 (2010)
6560e6564.
[24] T. Suzuki, R. Tanaka, S. Hamada, H. Nakagawa, N. Miyata, Bioorg. Med. Chem.
20 (2010) 1124e1127.
[25] A.B. Burtoloso, A.L. Garcia, K.C. Miranda, C.D. Correia, Synlett 18 (2006)
3145e3149.
[26] S.G. Stewart, M.E. Polomska, R.W. Lim, Tetrahedron Lett. 48 (2007)
2241e2244.
[27] C. Peifer, T. Stoiber, E. Unger, F. Totzke, C. Schachtele, D. Marme, R. Brenk,
G. Klebe, D. Schollmeyer, G. Dannhardt, J. Med. Chem. 49 (2006) 1271e1281.

N.S. Patil et al. / European Journal of Medicinal Chemistry 83 (2014) 490e497
497
[28] J. Trapp, A. Jochum, R. Meier, L. Saunders, B. Marshall, C. Kunick, E. Verdin,
P. Goekjian, W. Sippl, M. Jung, J. Med. Chem. 49 (2006) 7307e7316.
[29] S. Routier, J. Merour, N. Dias, A. Lansiaux, C. Bailly, O. Lozach, L. Meijer, J. Med.
Chem. 49 (2006) 789e799.
[30] M. Sortino, V. Filho, R. Correa, S. Zacchino, Bioorg. Med. Chem. 16 (2008)
560e568.
[31] P. Aqueveque, T. Anke, O. Sterner, Z. Naturforsch., C., Biosci. 57c (2002)
257e262.
[32] T.N. Bansode, J.V. Shelke, V.G. Dongre, Eur. J. Med. Chem. 44 (2009)
5094e5098.
[33] M. Sortino, F. Garibotto, V. Filho, M. Gupta, R. Enriz, S. Zacchina, Bioorg. Med.
Chem. 19 (2011) 2823e2834.
[34] X. Li, D. Zhang, H. Pang, F. Shen, H. Fu, Y. Jiang, Y. Zhao, Org. Lett. 7 (2005)
4919e4922.
[35] S. Bhagat, A.K. Chakraborti, J. Org. Chem. 72 (2007) 1263e1270.
[36] B. Das, G. Satyalakshmi, K. Suneel, K. Damodar, J. Org. Chem. 74 (2009)
8400e8402.
[50] L. Ning, W. Wang, Y. Liang, H. Peng, L. Fu, H. He, Eur. J. Med. Chem. 48 (2012)
379e384.
[51] C.B. Reddy, K.S. Kumar, M.A. Kumar, M.V. Reddy, B.S. Krishna, M. Naveen,
M.K. Arunasree, C.S. Reddy, C.N. Raju, C.D. Reddy, Eur. J. Med. Chem. 47 (2012)
553e559.
[52] A.K. Bhattacharya, D.S. Raut, K.C. Rana, I.K. Polanki, M.S. Khan, S. Iram, Eur. J.
Med. Chem. 66 (2013) 146e152.
[53] Z. Rezaei, H. Firouzabadi, N. Iranpoor, A. Ghaderi, M.R. Jafari, A.A. Jafari,
H.R. Zare, Eur. J. Med. Chem. 44 (2009) 4266e4275.
[54] W.M. Abdou, R.E. Khidre, Abeer A. Shaddy, J. Heterocycl. Chem. 50 (2013) 33.
[55] P. Jansa, O. Hradil, O. Baszczynski, M. Dracínsky, B. Klepetarova, A. Holy,
J. Balzarini, Z. Janeba, Tetrahedron 68 (2012) 865e871.
[56] A. Holy, Antiviral. Res. 71 (2006) 248e253.
[57] H. Elayadi, M. Smietana, C. Pannecouque, P. Leyssen, J. Neyts, J. Vasseur,
H.B. Lazrek, Bioorg. Med. Chem. 20 (2010) 7365e7368.
[58] S.D. Lombaer, L. Blanchard, C. Berry, R.D. Ghai, A.J. Trapani, Bioorg. Med. Chem.
5 (1995) 151e154.
[37] S. Delarue-Cochin, J. Pan, A. Dauteloup, F. Hendra, R.G. Angoh, D. Joseph,
P.J. Stephens, C. Cave, Tetra Asymm. 18 (2007) 685e691.
[38] A.A. Yurkova, E.A. Khakina, S.I. Troyanov, A. Chernyak, L. Shmygleva,
A.S. Peregudov, V.M. Martynenko, Y.A. Dobrovolskiy, P.A. Troshin, Chem.
Commun. 48 (2012) 8916e8918.
[39] K. Nakanishi, S. Kotani, M. Sugiura, M. Nakajima, Tetrahedron 64 (2008)
6415e6419.
[40] R. Engel, Chem. Rev. 77 (1977) 349e367.
[41] A.H. Kategaonkar, R.U. Pokalwar, S.S. Sonar, V.U. Gawali, B.B. Shingate,
M.S. Shingare, Eur. J. Med. Chem. 45 (2010) 1128e1132.
[42] G.S. Prasad, M. Manjunath, K.R.K.K. Reddy, O.V.S. Reddy, C.S. Reddy, Arkivoc
xvi (2006) 128e135.
[43] O. Dogan, H. Babiz, A.G. Gozen, S. Budak, Eur. J. Med. Chem. 46 (2011)
2485e2489.
[44] W.M. Abdou, M.D. Khidre, R.E. Khidre, Eur. J. Med. Chem. 44 (2009) 526e532.
[45] A.H. Kategaonkar, S.S. Sonar, S.B. Sapkal, V.U. Gawali, B.P. Shingate,
M.S. Shingare, Phosphorus, Sulfur Silicon 185 (2010) 2113e2121.
[46] N. Nguyen, S. Soroush, S. Meredith, P. Keykavous, Bioorg. Med. Chem. 12
(2004) 6255e6269.
[47] P. Jansa, O. Baszczynski, M. Dracinsky, I. Votruba, Z. Zidek, G. Bahador,
G. Stepan, T. Cihlar, R. Mackman, A. Holy, Z. Janeba, Eur. J. Med. Chem. 46
(2011) 3748e3754.
[59] S. Gobec, I. Plantan, J. Mravljak, R.A. Wilson, G.S. Besra, D. Kikelj, Bioorg. Med.
Chem. 14 (2004) 3559e3562.
[60] P. Srivastava, A.K. Tiwari, N. Chadha, K. Chuttani, A.K. Mishra, Eur. J. Med.
Chem. 65 (2013) 12e20.
[61] S.S. Sonar, A.H. Kategaonkar, M.N. Ware, C.H. Gill, B.B. Shingate, M.S. Shingare,
ARKIVOC ii (2009) 138e148.
[62] V.S. Abramov, Dokl. Akad. Nauk. SSSR 73 (1950) 487e489.
[63] V.S. Abramov, Zh. Obshch. Khim. 22 (1952) 647e652.
[64] S.V. Patil, K.A. Mahale, K.S. Gosavi, G.B. Deshmukh, N.S. Patil, Org. Prep. Proc.
Int. 45 (2013) 314e320.
[65] M.K. Sahoo, S.B. Mhaske, N.P. Argade, Synthesis 3 (2003) 346e349.
[66] E.K. Field, J. Am. Chem. Soc. 74 (1952) 1528e1532.
[67] A.N. Pudovik, Dokl. Akad. Nauk. SSSR 73 (1950) 499e502.
[68] O. Gawron, C. Grelecki, W. Reilly, J. Sands, J. Am. Chem. Soc. 75 (1953)
3591e3592.
[69] F. Texier-Boullet, A. Foucaud, Synthesis (1982) 165e166.
[70] V.J. Blazis, K.J. Koeller, C.D. Spilling, J. Org. Chem. 60 (1995) 931e940.
[71] A.R. Sardarian, B. Kaboudin, Synth. Commun. 27 (1997) 543e551.
[72] A.N. Pudovic, M.G. Zimin, A.A. Sobanov, A.A. Musina, Zh. Obshch. 46 (1976)
1455e1457.
[73] F. Texier-Boullet, A. Foucaud, Synthesis (1982) 916e922.
[74] E.E. Nifant’ev, T.S. Kukhareva, T.N. Popkova, O.V. Davydocchkina, Zh. Obshch.
Khim 56 (1986) 304e306.
[75] T. Yokomatsu, T. Yamagishi, S.J. Shibuya, Chem. Soc. Perkin Trans. I (1997)
1527e1534.
[48] J. Parrish, L. Tong, M. Wang, X. Chen, E. Lansdon, C. Cannizzaro, X. Zheng,
M.C. Desai, L. Xu, Bioorg. Med. Chem. 23 (2013) 1493e1497.
[49] M.V. Lee, E.M. Fong, F.R. Singer, R.S. Guenette, Cancer Res. 61 (2001)
2602e2608.