Facile syntheses of Mannich bases of 3-[p-(5-arylpyrazolin-3-yl)phenyl] sydnones, as anti-tubercular and anti-microbial agents, under ionic liquid/tetrabutylammonium bromide catalytic conditions

Article abstract of DOI:10.2298/JSC100708085T

Novel methylene bridged Mannich bases 2a-j were synthesized in good to excellent yields from the pyrazoline derivative 1 using various primary/ secondary amines, 37 % formalin in presence of ionic liquids/TBAB as catalyst. The structures of the newly synt

Full text of DOI:10.2298/JSC100708085T

J. Serb. Chem. Soc. 76 (8) 1069–1079 (2011)
JSCS–4185
UDC 542.913+547.772+547.233–316+
544.354.5:615.28–188
Original scientific paper
Facile syntheses of Mannich bases of 3-[p-(5-arylpyrazolin-3-
-yl)phenyl]sydnones, as anti-tubercular and anti-microbial
agents, under ionic liquid/tetrabutylammonium bromide
catalytic conditions
1
1
1
*
TASNEEM TAJ , RAVINDRA R. KAMBLE , TEGGINMATH M. GIREESH
and RAVINDRA K. HUNNUR2
1PG Department of Studies in Chemistry, Karnatak University Dharwad-580 003 and
2APL Research Centre, A Division of Aurobindo Pharma Ltd. 313,
Batchupally, Hyderabad-500 072, India
(Received 8 July 2010, revised 7 January 2011)
Abstract: Novel methylene bridged Mannich bases 2a–j were synthesized in
good to excellent yields from the pyrazoline derivative 1 using various prima-
ry/secondary amines, 37 % formalin in presence of ionic liquids/TBAB as ca-
talyst. The structures of the newly synthesized compounds were confirmed by
IR, 1H- and 13C-NMR and GC–MS spectroscopy, as well as elemental analysis.
The title compounds were screened for their anti-tubercular and antimicrobial
activities. Some of the compounds exhibited very good anti-tubercular, antifun-
gal and antibacterial activities.
Keywords: pyrazoline; Mannich base; ionic liquids; TBAB; MIC; anti-tubercu-
lar activity.
INTRODUCTION
Multidrug-resistant tuberculosis is perceived as a growing hazard to human
health worldwide. The fear is that the number of cases resistant to anti-tubercular
1
drugs is on the increase. One of the strategies suggested for overcoming this
problem is to exploit the potential of standard short course chemotherapy based
on the cheap and safe first line drugs. Furthermore, there is an urgent need for the
development of new potent anti-tubercular drugs without cross resistance with
2,3
known antimycobacterial agents. This has stimulated scientists to develop no-
vel molecules to combat these illnesses. Pantothenate synthetase (PS) is one of
the potential new antimicrobial targets which are useful for the treatment of non-
replicating persistent forms of Mycobacterium tuberculosis (Mtb). Therefore, the
*Corresponding author. E-mail: kamchem9@gmail.com
doi: 10.2298/JSC100708085T
1069
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TASNEEM TAJ et al.
discovery and development of drugs effective against non-replicating persistence
(NRP) Mtb are considered as the highest priority among tetrabutyl (TB) drug dis-
4
covery efforts.
Reports convey that Mannich bases possess anti-inflammatory, antibacterial,
antifungal and antihistamine activities. The synthesis of pyrazole and its N-aryl
analogues has been the subject of consistent interest because of the wide range of
applications of such heterocycles in the pharmaceutical and agrochemical Indus-
tries. Numerous compounds containing the pyrazole moiety have exhibited anti-
hyperglycemic, analgesic, anti-inflammatory, antipyretic, antibacterial and seda-
5–9
tive–hypnotic activity.
The role of the added pyrazole ring could be to in-
crease the electron density of the system and makes the chromophore more re-
sistant towards enzymatic reduction by radical species. In addition, some syd-
10
none derivatives have been reported as potential anti-tubercular agents.
Recently, ionic liquids (ILs), a kind of ion solvent, which combine the ad-
vantages of both traditional molecular solvents and melt salts, have been consi-
dered as promising new reaction media, and have found wide use in catalytic and
non-catalytic reactions as these materials dissolve many organic as well as in-
organic substances. In addition, they can be easily recycled. Moreover, their pro-
11–14
perties are tunable to satisfy specific chemical tasks.
The above observations prompted us to explore the synthetic utility of pyra-
zoline derivatives using ionic liquids or tetrabutylammonium bromide (TBAB) as
catalysts in the synthesis of novel Mannich bases intact with the sydnone moiety,
giving novel biodynamic molecules 2a–j in order to evaluate their antimicrobial
and anti-tuberculosis activity.
EXPERIMENTAL
Chemistry
Melting points were determined in open capillaries and are uncorrected. The IR spectra
1
were recorded on a Nicolet Impact 5200 USA FT-IR instrument using KBr pellets. The H-
-NMR and 13C-NMR spectra were recorded on a Bruker Varian 300-MHz FT-NMR spectro-
meter with TMS as the internal standard. The mass spectra were recorded on Shimadzu Japan
QP2010 S spectrometer and the elemental analyses were realized using Heraeus CHN rapid
analyzer. The purity of the compounds was checked by thin layer chromatography (TLC) on
silica gel plates using benzene and ethyl acetate as eluents. The pharmacological evaluations
were performed at the Department of Microbiology and Immunology, NGH College of Dental
sciences, Belgaum, Karnataka, India. The log P values were calculated using ACD Chem-
sketch software for the structural analogues of the synthesized compounds and are uncor-
rected.
The pyrazoline derivative 1 required for the present work was prepared by the reaction of
the chalcone and hydrazine hydrate according to a reported method.15 The acidic ionic liquid
catalysts were synthesized according to literature procedures.16 Commercially available
TBAB was used for the reaction at 10 mol %. The pyrazoline derivative 1 upon reaction with
primary/secondary amines in presence of 37 % formalin and an ionic liquid as catalyst gave
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ANTI-TUBERCULAR AND ANTI-MICROBIAL MANNICH BASES
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the Mannich bases 2a–j (Scheme 1). All the products are solids, with exception of the com-
pounds 2d and 2f which were isolated as semisolids.
H
H
N
H
R
N
i, ii
O
N
N
N
N
O
N
iii,
IL/TBAB
N
Ph
R'
O
N
Ph
O
1
2 (a-j)
H
S
N
O
N
(H2C)5
R =
N
N
N
S
R' = H
H
g,
a,
R =
N
O
Ph
R' = H
R = R' = NH2CH2CH2
b, R = R' = OHCH2CH2
c,
h,
i,
R =
t- butyl-
R' =H
R' = H
O
N
R =
-
R = CH3CH2CH2CH2
R' = H
d,
e,
N
N
H2N
R =
N
NH
R' = H
j, R =
R' = H
N
N
N
NH2
f,
R = R' = Ph
Scheme 1. Synthesis of Mannich bases 2a–j.
Preparation of 3-[4-(5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)phenyl]sydnone (1)
The pyrazoline derivative 1 was synthesized according to a literature method.17 Yellow
solid. Yield: 80 %, m.p. 171–173 °C.
Preparation of 2a–j
To the slurry of compound 1 (0.01 mol), 50 % aqueous ethanol (5 ml) and 37 % formalin
(5 ml) was added dropwise an amine (0.01 mol) and an ionic liquid catalyst (0.01 mmol) with
cooling and shaking. The reaction mixture was allowed to stand at RT for 1 h with occasional
stirring after which it was warmed on a steam bath for 3 h for the conventional synthesis
method. When using an ionic liquid 10 mol %, the reaction time was unchanged. The catalyst
was recovered by extracting with diethyl ether.
When TBAB was used as catalyst, the reaction time was 2 h. At the end of this period,
the solvent was evaporated and the contents were cooled. The products thus separated were
filtered and recrystallized (except 2d and 2f) in ethanol, petroleum ether and chloroform.
Biological assays
Antimicrobial assay. Preliminary screening was conducted for all the compounds at 100
µg ml-1 concentration against two Gram-positive bacteria, Staphylococcus aureus – ATCC
25293 and Bacillus subtilis – ATCC 6633 and Gram-negative bacteria Pseudomonas aerugi-
nosa – ATCC 10145 and Escherichia coli – ATCC 35218, and against two fungal strains
Candida albicans 10231 and Candida fumigatus 74359.
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The protocol for the antimicrobial activity assay was as follows.18
Dimethylformamide was used as the solvent control. The bacterial cultures were inocu-
lated on Mueller Hinton Agar (Merck) and fungal cultures on Potato Dextrose Agar. Media
(20 ml) were poured into each sterilized Petri dish (99 mm) and media were inoculated homo-
geneously with the liquid cultures by the spread plate method. All the compounds were dis-
solved in dimethyl sulfoxide (DMSO) to obtain a concentration of 100 µg/µl. Each sample
(100 µl) was directly loaded into the wells of agar plates. The plates inoculated with bacteria
were incubated at 37 °C for 24 h and the fungal cultures were incubated at 25 °C for 72 h. All
the determinations were performed in triplicate. The standards ampicillin (100 µg ml-1) for the
antibacterial and clotrimazole (100 µg ml-1) for the antifungal assays were used as the positive
controls and 100 µl of DMSO was used as the negative control. The zones of inhibition were
recorded in mm.
Different series of dilutions of the compounds were made (0.5–10.0 µg ml-1) to de-
termine the minimum inhibitory concentration (MIC).
Anti-tubercular assay. The anti-tubercular activity of the test compounds were evaluated
against the standard strain of Mycobacterium tuberculosis H37Rv. The antibiotic standards
used were streptomycin and pyrazinamide. The procedure followed for the anti-tubercular
activity assay involved the use of Middlebrook 7H-9 broth. The basal medium was prepared
according to the manufacturer’s instructions (Hi-Media) and sterilized by autoclaving. Then,
4.5 ml of broth was poured into every sterile bottle. To this, 0.5 ml of albumin dextrose
catalase (ADC) supplement consisting of catalase, dextrose and bovine serum albumin (BSA)
fraction v was added. Then, a stock solution of the test compound was prepared (10 mg ml-1).
From this, appropriate amounts of the solution were transferred to the media bottles to achieve
final concentrations of 25, 50, 100 µg ml-1. Finally, 10 µl of a suspension of M. tuberculosis
H37Rv strain (105 organisms ml-1, adjusted by the McFarmland turbidity standard) was
transferred to each of the bottles and incubated at 37 °C. Together with these, a growth control
without the compound and drug controls were also set up. The bottles were inspected for
growth twice a week for a period of three weeks. The appearance of turbidity indicated the
growth and inferred resistance to the compound. The growth was confirmed by making a
smear from each bottle and performing a Ziehl–Neelsen (ZN) stain.
RESULTS AND DISCUSSION
The synthesis of the investigated compounds by the conventional method re-
sulted into low yields. Use of ionic liquids 1–4 enhanced the yields, but phase
transfer catalyst (PTC) method using TBAB gave excellent yields along with
increased reaction rates. Various ionic liquids (IL1–IL4) and TBAB catalysts
were tried at different concentrations and finally it was observed that 10 mol %
of the catalyst (ionic liquids and TBAB) gave good yields (Table I). For the syn-
thesis of long chain alkylated Mannich bases, viz., 2d and 2g, IL3 and IL4 gave
poor yields as the products could not be isolated in the desired quantity as either
solids or semisolids, which posed great difficulty for product characterization.
For the other compounds, the catalyst used and the range of yields are depicted in
Table II. The ionic liquids which gave better results are also reported. It is in-
teresting to note that the TBAB catalyst gave excellent yields for all the final
compounds. The reaction time was unchanged when an ionic liquid (10 mol %)
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ANTI-TUBERCULAR AND ANTI-MICROBIAL MANNICH BASES
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was used, whereas the use of TBAB reduced the reaction time to 2 h. The ionic
–
liquid Hmim Tsa (IL1) gave better yields for the final compounds 2a, 2e and 2i,
–
whereas the yields of compounds 2b, 2c, 2f and 2j were good when Hmim SO
4
–
(IL2) was used. The catalytic activities of Bmim [H PO ] (IL3) and Bmim
[HSO ] (IL4) were much lower and the yields of 2d and 2h were negligible
2
4
–
4
under IL3 and IL4 conditions. The ionic liquids IL1 and IL2 did not give the
products 2d and 2g.
TABLE I. Methods and catalysts employed for the reactions (10 mol %) and the obtained yields
Catalyst
Yield range, %
Conventional method
Ionic liquids method
Without catalyst
60–70
Hmim Tsa– (IL1)
Hmim SO4– (IL2)
Bmim [H2PO4]– (IL3)
Bmim [HSO4]– (IL4)
TBAB
65–75
68–76
30–35
25–34
80–85
TABLE II. Yields of the respective compounds using the conventional method and employing
catalysts
Method
Conventional
Yield, %
Ionic liquids
TBAB
Yield, %
Compound
Catalyst
Yield,%
2a
2b
2c
2d
2e
2f
2g
2h
2i
67
65
68
69
70
64
66
67
69
66
IL1
1L2
IL2
IL3
IL1
IL2
IL4
IL2
IL1
IL2
70
72
75
–
70
72
34
74
75
77
82
85
84
78
87
89
85
80
88
85
2j
The structures of the Mannich bases 2a–j, given in the Supplementary mate-
1
13
rial, were confirmed by IR, NMR ( H- and C-), MS and elemental analyses, the
data are also given as Supplementary material. In their IR spectra, all the com-
–1
pounds exhibited a common strong absorption band at around 1748–1754 cm
–1
and a medium intensity sharp band at around 2950–3150 cm , due to ν(C–H) of
sydnone ring. In addition, another common sharp band was observed at around
–1
1580–1595 cm , due to C=N stretching frequencies of the pyrazoline ring.
–1
Compound 2a showed a weak absorption band at around 1420 cm due to
C=S stretching. Compound 2b exhibited a broad band at about 3427 cm due to
–1
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the two OH groups. Similarly, 2c and 2d showed sharp medium bands at 3426
–1
and 3444 cm arising from N–H stretching. Two weak stretching bands at
–1
around 3405 and 3415 cm were present in the spectrum of compound 2e due to
the symmetric and asymmetric stretching frequencies of NH groups attached to
2
the triazine ring. Compound 2g did not show any other significant bands except
–1
strong absorption at 2930 and 2922 cm due to CH stretching. Compound 2h
2
–1
also presented two weak bands at around 3439 and 3445 cm due to N–H stretch-
ing. Compounds 2i and 2j did not show any other significant stretching bands.
1
The H-NMR spectral analysis of the title compounds resulted in the follow-
ing observations. All the compounds gave a singlet in the range δ 6.65–6.75 ppm
due to the proton attached at the C carbon of the sydnone ring. The protons of
4
the pyrazole ring, i.e., the methine proton and the diastereotopic methylene pro-
tons exhibited a characteristic ABX pattern. The methylene protons can be as-
signed as H and H and the methine proton as Hx. H and H are diastereo-
A
B
A
B
topic and also anisochronous as they differ in their chemical shift and since this
difference is not large, they are identified as AB protons. The methine proton on
the adjacent carbon with a larger downfield shift is the Hx proton and all to-
gether, they form an ABX pattern. The H and H protons appear as doublet of
A
B
doublets due to geminal and vicinal coupling. These H and H differ in coup-
A
B
ling with Hx and hence they are also anisogamous. The H proton appears as a
A
doublets of doublet in the range δ 3.48–3.73 ppm with two coupling constants,
J
AB
= 17.6 Hz and J = 4.5Hz. H also appears as doublet of doublets at 3.08–
Ax B
–3.47 ppm, whereby J = 17.6 Hz and J = 11.8 Hz. The Hx proton always
BA
BX
appears as a four-line spectrum with J
= 4.49 Hz and J
= 11.84 in the δ
XA
XB
range 4.32–4.92 ppm. The methylene protons attached to the nitrogen of pyrazole
appear in the δ range 3.50–3.75 ppm.
1
The H-NMR spectrum of 2a showed a singlet at δ 3.45 ppm for two protons
due to presence of methylene groups. The aromatic protons appear as a multiplet
in the δ range 7.32–7.76 ppm due to protons on benzothiazoline-2-thione and the
1
phenyl ring attached to the pyrazoline ring. The H-NMR spectrum of 2b showed
a singlet at δ 3.64 ppm for two protons due to the presence of methylene groups
attached to the nitrogen atom of the pyrazoline ring. The remaining two sets of
methylene groups appeared as two sets of triplets at δ 4.38 (those attached to nit-
rogen) and 4.83 ppm (those attached to the OH group). The aromatic protons
appeared as a multiplet in the region δ 7.27–7.87 ppm for nine protons.
1
Compound 2c exhibited the following H-NMR signature. A singlet for 9
protons was observed at δ 1.78 ppm due to t-butyl and another singlet at δ 3.64
ppm for 2 protons due to the methylene group. Similarly, a broad singlet was ob-
served at 5.15 ppm (D O exchangeable) due to NH protons. Compound 2d showed
2
a singlet at δ 3.71 ppm due to the methylene group present in between the py-
razoline ring and the butylamine moiety and another singlet at δ 4.92 ppm (D O
2
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ANTI-TUBERCULAR AND ANTI-MICROBIAL MANNICH BASES
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exchangeable). The n-butyl group attached to the nitrogen atom gave a triplet at δ
1.05 ppm due to the methyl protons and another triplet in the range δ 4.11 ppm
due to methylene protons attached to the nitrogen. The two methylene groups
present in between the methyl and the methylene adjacent to the nitrogen appear
as a multiplet in the range δ 2.70–2.96 ppm. The aromatic protons appear as mul-
tiplets in the region δ 6.77–7.83 ppm.
Compound 2e showed a singlet at δ 3.71 ppm and a broad singlet at δ 5.08
(D O exchangeable) due to NH protons, whereas compound 2f showed a com-
2
2
plex multiplet within the range 7.03–8.21 ppm for 19 aromatic protons. A multi-
plet at δ 1.34–2.40 ppm of 10 aliphatic protons was observed for compound 2g,
in which the 5 methylene group chain is flanked by two pyrazoline phenylsyd-
none groups. This compound also exhibited two doublets of doublets for 4 pro-
tons and one four line spectrum as a doublet of doublets for 2 methine protons,
one in each lead pyrazoline ring. Compound 2h showed a multiplet for 4 protons
at δ 0.88–2.17 ppm due to the two sets of methylene protons attached to nitrogen
atoms and another set of 2 protons as a singlet at 3.53 ppm.
A multiplet at δ 2.45–2.63 ppm appeared due to the methylene protons of
morpholine in the spectrum of compound 2i. Compound 2j exhibited a singlet
due to the methylene group spaced between the benzotriazole and the pyrazole
ring at δ 3.75 ppm. The aromatic protons appeared as multiplet in the range δ
7.28–7.89 ppm.
13
The C-NMR spectra of all the compounds showed signals in the respective
regions.
Furthermore, in the electron impact studies, all the compounds showed mo-
lecular ion peaks at their respective m/z value.
Antibacterial activity assay
The MIC values for compounds 2a–j and the standard obtained in the in
–1
vitro anti-bacterial studies, which ranged from 0.5–4 µg ml , are given in Table
III. These activities are comparable to those of a number of common pyrazole
derivatives reported in the literature. The anti-bacterial activity of all the com-
pounds against S. aureus, B. subtilis, P. aeruginosa and E. coli showed good po-
tencies compared to the control drug ampicillin. From the results, it is apparent
that among the synthesized compounds 2a, 2b and 2f showed excellent activity
–1
against B. subtilis with MIC values 0.5–1.5 µg ml , and P. aeruginosa with va-
–1
lues of 1–2.5 µg ml . Compounds 2c, 2e, 2f, 2h and 2j showed potent inhibition
–1
against S. aureus with values ranging from 1–3 µg ml . Compounds 2a, 2f and
–1
2j showed good activity against E. coli with values of 1–3 µg ml . Among the
ten screened compounds, almost all of them exhibited promising inhibition against
the bacterial cultures compared to the control drug ampicillin.
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Antifungal activity assay
The MIC values for compounds 2a–j and the standard in the in vitro anti-
-fungal studies are represented in Table III. Among the test compounds, interest-
ing activities were found for compounds 2a, 2b, 2f, 2e, 2g, and 2i, which showed
–1
potent inhibition against C. albicans with MIC values in the range 1.5–3 µg ml .
Compounds 2b, 2c and 2i possessed favorable MIC values against C. fumigatus,
–1
having values in the range 2–3.5 µg ml . The anti-fungal activities indicated that
some of the derivatives exhibited a broad spectrum of activity against the tested
fungi, with compounds having electron donating groups appended to the pyrazole
moiety exhibiting a better spectrum of activity than the reference drug clotrima-
zole.
TABLE III. Antibacterial and antifungal activities (MIC / µg ml-1) of the compounds 2a–j
(control: DMSO)
B. subtilis S. aureus
ATCC 6633 ATCC 25293 ATCC 35218 ATCC 10145 ATCC 10145 ATCC 74359
E. coli
P. aeruginosa C. albicans C. fumigates
Entry No.
2a
2b
2c
2d
2e
2f
2g
2h
1.5
2
0.5
0.5
0.5
1
0.5
0.5
1
1
1
3
3
2.5
3
1.5
2
2
2
1
3
2
1.5
1
2
3
2
2
2
3
3.5
3.5
2
2.5
2
3.5
1
2
3
4
1.5
2
3
3.5
4
2
3
1.5
–
2
2
3.5
3.5
2.5
2
2
3
3
2
2i
2j
1.5
1.5
2
1
0.5
–
2.5
–
2
Ampicillin
Clotrimazole
2
–
–
–
Anti-tubercular activity assay
The results of the anti-tubercular activity studies are given in Table IV, from
which it can be seen that the compounds with electron donating groups viz., 2c,
2d, 2e, 2g and 2i exhibited excellent inhibition (MIC) at a concentration of less
–1
than 5 µg ml . Compounds 2b, 2f, 2h and 2j showed moderate inhibition at a
–1
concentration of 10 µg ml . Compound 2a with benzothiazoline-2-thione showed
–1
activity only at a concentrations of 25 µg ml as compared to the standards used,
–1
–1
viz., streptomycin (7.5 µg ml ) and pyrazinamide (10 µg ml ). The encouraging
activities are attributed to the presence of long alkylating chains with electron do-
nating groups, viz., OH, NH , methylene and ethylene through mesomeric effect,
2
appended to the pyrazoline moiety.
The log P values of the compounds are given in Table V. To qualify a com-
pound as a drug candidate, it is analyzed by the parameters set by the Lipinski
rule of five. The log P value is an important physico-chemical property indi-
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ANTI-TUBERCULAR AND ANTI-MICROBIAL MANNICH BASES
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cating lipophilicity and the ability of a molecule to cross the various biological
membranes. According to the Lipinski rule of five, with a log P value below 5, it
is feasible for a compound to be future drug. The synthesized compounds showed
marginal lipophilicity within the range of 1.20–5.0. The molecular weight of a
compound is related to its in vivo administration. All the synthesized compounds
–1
had a molecular weight within the acceptable range, i.e., 400–500 g mol .
TABLE IV. Anti-tubercular activity of the synthesized compounds (Strain H37Rv); standard:
streptomycin, 7.5 µg ml-1, pyrazinamide, 10 µg ml-1; all compounds tested at concentrations
of 5, 10 and 25 µg ml-1
Entry No.
MIC / μg ml-1
2a
2b
2c
2d
2e
2f
2g
2h
2i
25
4.5
5
3.5
5
10
5
10
3.5
12
2j
TABLE V. The calculated log P values of the newly synthesized compounds
Entry No.
log P
1
2a
1.83
3.73
2b
1.49
2c
2.41
2d
2.77
2e
1.20
2f
5.03
2g
2h
Not applicable
1.38
2i
1.62
2j
2.96
INH
Nifuroxazide
0.887
0.059
According to the Lipinski rule, a less than five-heteroatom moiety can be
considered as a probable candidate as a drug. The log P values depict the
penetration of the drug into the cell membrane. As value of log P value increases,
the penetration also increases. Compounds 2b, 2c, 2d, 2e and 2i showed low MIC
values and high log P values, which show that these moieties have better
penetration values and can be considered for further studies as drugs.
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TASNEEM TAJ et al.
CONCLUSIONS
A simple and efficient method for the synthesis of novel methylene-bridged
Mannich bases of benzothiazoline-2-thione, morpholine, biphenyl and benzotri-
azole derivatives was developed. It is believed that the procedural simplicity, the
efficiency and the easy accessibility of the reaction partners give access to a wide
array of heterocyclic frameworks equipped with a pendant pyrazoline unit. The
use of environmental friendly catalysts, viz., an ionic liquid and TBAB is an
added advantage. TBAB as a catalyst gave excellent results in terms of yields.
The results of the anti-tubercular screening revealed that of the ten synthe-
sized compounds, five showed good inhibition while the other five compounds
displayed moderate to low inhibition.
SUPPLEMENTARY MATERIAL
Structures of the prepared compounds and their spectral data are available electronically at
http://www.shd.org.rs/JSCS/, or from the corresponding author on request.
И З В О Д
ЈЕДНОСТАВНА СИНТЕЗА МАНИХОВИХ БАЗА 3-[p-(5-АРИЛ-ПИРАЗОЛИН-3-ИЛ)-
-ФЕНИЛ]СИДНОНА У ПРИСУСТВУ КАТАЛИТИЧКИХ КОЛИЧИНА TBAB/ЈОНСКЕ
ТЕЧНОСТИ, КАО АНТИ-ТУБЕРКУЛОЗНИХ И АНТИ-МИКРОБНИХ АГЕНАСА
TASNEEM TAJ1, RAVINDRA R. KAMBLE1, T. M. GIREESH1 и RAVINDRA K. HUNNUR2
1PG Department of Studies in Chemistry, Karnatak University Dharwad-580 003 и 2APL Research Centre,
A Division of Aurobindo Pharma Ltd. 313, Batchupally, Hyderabad-500 072, India
Синтетисане су нове Манихове базе 2a–j, у добром до одличном приносу, полазећи од
пиразолинског деривата 1 употребом различитих примарних/секундарних амина и 37 %
формалдехида, у присуству каталитичких количина TBAB/јонске течности. Структура нових
једињења потврђена је IC, NMR (1H-, 13C-), GC-MS и елементалном анализом. Испитана је
антитуберкулозна и антимикробна активност добијених једињења. Нека од њих показују
веома добру антитуберкулозну, антифунгалну и антибактеријску активност.
(Примљено 8. јула 2010, ревидирано 7. јануара 2011)
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