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Research Article
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Synthesis and Studies on Some New Fluorine Containing Hydroxypyrazolines and 1H Pyrazoles-as Possible Antiproliferative Agents |
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B. Sooryanarayana Rao,
P.M. Akberali ,
B. Shivarama Holla
and
B.K. Sarojini
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ABSTRACT
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A series of twenty four newly synthesized 1-aroyl-3-aryl-5-hydroxy-5-(2,4-dichloro-5-fluorophenyl) pyrazolines (3) and 1H-3-aryl-5-hydroxy-5-(2,4-dichloro-5-fluorophenyl)-pyrazoles (6) were tested for cytostatic and cytotoxic effects on in a primary three cell line-one dose anticancer assay against NCI-H 460 (Lung), MCF 7(Breast) and SF 268 (CNS). Proliferation of these cancer cell lines was strongly inhibited by eleven compounds. These eleven compounds were then passed on for evaluation in the full panel of 60 cell lines derived from seven cancer types namely, Lung, Colon, Melanoma, Renal, Ovarian, CNS and Leukemia. These compounds showed antiproliferative activity on the whole cell panel. Compound 1H-pyrazole, 6d [3,4-methylenedioxy at C 3] showed highest activity with Growth Inhibition (GI50) value < 10 μM against all tested 60 cell lines except for Leukamia CCRF-CEM, HL-60TB, K-562 cell lines. Whereas hydroxypyrazolines 3i, 3k 3m, 3o, 3p and 3q showed moderate activity with GI50 value < 50 μM against all tested 60 cell lines. Compounds 3h, 3c, 6c appear to be less active with GI50 value >100 μM for some of the tested cell lines. Compound 6a appears to be least active with GI50 value >100 μM for almost all the tested cell lines. The Total Growth Inhibition (TGI) and Lethal Concentration (LC50) values for the most active compound [6d] found to be >100 μM for Leukemia cell lines and for the other cell lines these values remain < 20 μM and hence prove to be a cytostatic and cytotoxic for these lines. Hence these newly synthesized pyrazole and pyrazoline derivatives showed promising antiproliferative property.
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How
to cite this article:
B. Sooryanarayana Rao, P.M. Akberali , B. Shivarama Holla and B.K. Sarojini , 2008. Synthesis and Studies on Some New Fluorine Containing Hydroxypyrazolines and 1H Pyrazoles-as Possible Antiproliferative Agents. Journal of Pharmacology and Toxicology, 3: 102-110.
DOI: 10.3923/jpt.2008.102.110
URL: https://scialert.net/abstract/?doi=jpt.2008.102.110
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INTRODUCTION
Pyrazolines have been reported to show a broad spectrum of biological activities
including antibacterial, antifungal, anti-inflammatory and antidepressant activities
(Elgeuro, 1984). The pyrazoline function is quite stable and has inspired chemists
to utilize this stable fragment in bioactive moieties to synthesize new compounds
possessing biological activities. The presence of fluorine in the molecules
at strategic positions alters the activity (Filler and Kabayashi, 1992). Chalcone
dibromides are very useful synthons in the synthesis of bioactive molecules
such as pyrazolines, pyrazoles, isoxazoles, flavones, flavonols, flavanones,
aurones, coumarones, tetralones, aziridines etc.
The anti-infective and anti-inflammatory properties of chalcone derivatives
were reviewed by Nowakowaska (Nowakowska, 2007). The literature survey revealed
that after 1989, the synthesis of hydroxy pyrazolines (Structure 1) was reported
mostly from Hollas group (Holla et al., 1989; Holla et al.,
2006; Holla et al., 2006; Holla et al., 2006; Karthikeyan et
al., 2007). Bonacorso and others (Bonacorso et al., 2006) reported
the regiospecific one step synthesis of heteroaroyl-2-pyrazolines under mild
conditions. Prompted by the biological activity of the pyrazole derivatives
the present work is undertaken.
This study presents the synthesis of hydroxypyrazolines, 1H-pyrazoles and to screen the newly synthesized heterocycles for their antiproliferative activity. MATERIALS AND METHODS
The synthesis of the target molecules 3 and 6 which is given in the Scheme
1 was carried out by B. Sooryanarayana Rao at the Department of Chemistry,
Mangalore University according to the reported procedure (Holla et al.,
1989) during his Ph.D. programme. Melting points were taken in open capillary
tubes and are uncorrected. IR spectra in KBr pellets were recorded on JASCO
FT-IR 5300 Infrared spectrophotometer. 1H NMR spectra were recorded
in DMSO-d6 on a Varian (300 MHZ) spectrometer using TMS as an internal
standard and the mass spectra were recorded on aVG-s-70 micro mass, mass spectrometer
operating at 70eV. The purity of the compounds were checked by TLC using ethylacetate:methanol
[8:2] solvent system. Iodine was used as visualizing agent. The characterization
data are given in the Table 1 and 2 and
spectral data are given in Table 3. The anticancer studies
were carried out at National Institute of Health, Bethesda, Maryland, USA under
the Drug Discovery programme
Antiproliferative Activity
The newly synthesized compounds 3 and 6 were screened for their antiproliferative
activities at NIH, Bethesda, Maryland, USA under the Drug Discovery Programme
of NCI according to the procedure suggested by Boyd and Paull (1995) in a primary
three cell line-one dose anticancer assay against NCI-H 460 (Lung), MCF 7(Breast)
and SF 268 (CNS). In the current protocol each cell line is inoculated on an
incubated micro titer plate. The test agents were added at a single concentration
and the culture was incubated for 48 h. Endpoint determinations were made with
Sulforhodamine B, a protein binding dye. Results for each test agents were reported
as the percent growth of the treated cells when compared with the untreated
control cells. Compounds which reduce the growth of any one of the cell lines
to 32% or less (negative numbers indicate cell kill) in a primary three cell
line-one dose anticancer assay were considered as active and these compounds
were then passed on to 60-cell line screening studies.
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Scheme 1: |
Synthesis of 1-aroyl-3-aryl-5-hydroxy-5-(2,4-dichloro-5-fluorophenyl)
pyrazolines (3) and 1H-pyrazoles (6) |
Table 1: |
Characterization data of 1-aroyl-3-aryl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazolines (3) |
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Table 2: |
Characterization data of 3-aryl-5-(2,4-dichloro-5-flurophenyl)-1(H)-pyrazoles
(6) |
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Table 3: |
Spectral data of some of the newly synthesized compounds |
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RESULTS AND DISCUSSION
In the present anticancer screening program of 1-aroyl-3-aryl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazolines, 1-benzoyl-3-phenyl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl) pyrazoline
3c, 1-4-chlorobenzoyl-3-(4-methoxyphenyl)-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3h, 1-(4-chlorobenzoyl)-3-(4-chlorophenyl)-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3k, 1-(4-chlorobenzoyl)-3-(3,4-dimethoxyphenyl)-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3i, 1-pyridoyl-3-phenyl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3m, 1-pyridoyl-3-(3,4-dimethoxyphenyl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3o, 1-pyridoyl-3-(4-chlorophenyl)-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3q, 1-pyridoyl-3-(3,4-methylinedioxyphenyl)-5-hydroxy-5-(2,4-dichloro-5-flurophenyl)
pyrazoline 3p and 1H pyrazoles 3-phenyl-5-(2,4-dichloro-5-flurophenyl) pyrazole
6a, 3-(3,4-dimethoxyphenyl)-5-(2,4-dichloro-5-flurophenyl) pyrazole 6c, (3,4-methylinedioxyphenyl)-5-(2,4-dichloro-5-flurophenyl)
pyrazole 6d, possessed growth percentage to less than 32% against all the tested
3 cancer cell lines and were regarded as active compounds.
Table 4: |
Preliminary in vitro anticancer screening a data of
Active 1-aroyl-3-aryl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl) pyrazolines
(3) and 3-aryl-5-(2,4-dichloro-5-flurophenyl)-1(H)-pyrazoles (6) |
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a: Fixed concentration assay (100 μM; standard
NCI protocol), b: Percent cell growth reduction following 48
h incubation with test compounds (optical density, sulforhodamine procedure),
c: Active when growth percentage is <32% for any of the three
cell lines |
Table 5: |
Sixty cell line in vitro anticancer screening of (3)
and (6) (GI50, μM) |
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Prescreen results are given in Table 4. These 6 compounds
were then passed on for evaluation in the full panel of 60 cell lines derived
from seven cancer types namely, Lung, Colon, Melanoma, Renal, Ovarian, CNS and
Leukemia. These compounds showed antiproliferative activity on the whole cell
panel. The screening data is presented in Table 5. Compound
1H-pyrazole 6d, (3,4-methylinedioxyphenyl)-5-(2,4-dichloro-5-flurophenyl) pyrazole,
showed highest activity with Growth Inhibition (GI50) value <10
μM against all tested 60 cell lines except for Leukamia CCRF-CEM, HL-60TB,
K-562 cell lines. Whereas hydroxypyrazolines 3i, 3k, 3m, 3o, 3p and 3q showed
moderate activity with GI50 value <50 μM against all tested
60 cell lines. Compounds 3h, 3c, 6c appear to be less active with GI50
value >100 μM for some of the tested cell lines. Compound 6a appears
to be least active with GI50 value >100 μM for almost all
the tested cell lines.
The most active compound 6d emerged as most effective against Non-small cell Lung cancer cells A549'ATCC = 2.93 μM, EKVX = 2.09 μM, HOP-62 = 2.36 μM, HOP-92 = 2.07 μM, NCI-H226 = 1.55 μM, NCI-H23 = 2.26 μM, NCIH322M = 2.73 μM, NCI-H460 = 3.12 μM, NCI-H522= 3.12 μM among the tested cell lines. The Total Growth Inhibition (TGI) and Lethal Concentration (LC50) values for the most active compound [6d] is given in Table 6. For leukemia cell lines both parameters are more than 100 μM and for the other cell lines these values remain less than 20 μM and hence proves to be a cytostatic and cytotoxic for these lines. With this information it is immature to comment on structure activity relationship. However, it appears that the presence of 3,4-methylenedioxy and pyridyl moieties may also contribute to their enhanced activity.
Table 6: |
Total Growth Inhibition (TGI) and Lethal Concentration (LC50)
of 3-(3,4-Methylenedioxy phenyl)-5-(2,4-dichloro-5-flurophenyl)-1(H)-pyrazole
(6d) |
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CONCLUSIONS With the history of pyrazole derivatives as potential bioactive moieties and in a hope to find potential molecules with antiproliferative activity we synthesized fluorine containing hydroxypyrazolines and pyrazoles. The newly synthesized compounds were characterized by analytical and spectral studies. In the present anticancer screening program of 1-aroyl-3-aryl-5-hydroxy-5-(2,4-dichloro-5-flurophenyl) pyrazolines, compounds 3c, 3h, 3k, 3i, 3m, 3o, 3q, 3p and 1H pyrazoles 6a, 6c, 6d were emerged as active compounds. 1H-pyrazole 6d [3,4-methylenedioxy at C 3] showed highest activity with Growth Inhibition (GI50) value <10 μM against all tested 60 cell lines except for Leukamia CCRF-CEM, HL-60TB,K-562 cell lines. Whereas hydroxy pyrazoline compounds 3i [3,4-methylenedioxyphenyl at C 3 and 4-chloro phenyl at C 1 substitution], 3k [4-chloro phenyl at C 3 and 4-chloro phenyl at C 1 substitution], 3m[phenyl at C3 and pyridyl at C1 substitution], 3o [3,4-dimethoxyphenyl at C3 and pyridyl at C1 substitution], 3p [3,4-methylenedioxyphenyl at C 3 and pyridyl at C1 substitution] and 3q [4-chloro phenyl at C 3 and pyridyl at C 1 substitution] showed moderate activity with GI50 value <50FM against all tested 60 cell lines. Compounds 3h [4-methoxyphenyl at C 3 and 4-chlorophenyl at C 1 substitution], 3c [3,4-dimethoxy phenyl at C 3 and phenyl at C 1 substitution] and 6c [3,4-dimethoxyphenyl at C 3] appear to be less active with GI50 value >100 μM for some of the tested cell lines. Compound 6a [phenyl at C 3 substitution] appears to be least active with GI50 value >100 μM for almost all the tested cell lines. The Total growth inhibition (TGI) and Lethal Concentration (LC50) values for the most active compound [6d] is given. For leukemia cell lines both parameters are >100 μM and for the other cell lines these values remain <20 μM and hence proves to be a cytostatic and cytotoxic for these lines. It appears that the presence of 3,4-methylenedioxy and pyridyl moieties may contribute to their enhanced activity. However, it is hoped that these pyrazole derivatives may emerge as potential compounds for antiproliferative activity. ACKNOWLEDGMENTS The authors are grateful to Head, R.S.I.C., C.D.R.I., Lucknow and The Director, R.S.I.C., Punjab University, Chandigarh, for providing microanalysis, IR, 1H NMR and mass spectral data. The authors are grateful to Dr. V.L. Narayanan, National Institutes of Health (NIH), Bethesda, Maryland, USA, for the antitumor activity screening studies reported in this research.
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REFERENCES |
Bonacorso, H.G., A.P. Wentz, R.V. Lourega, C.A. Cechinel and T.S. Moraes et al., 2006. Trifluoromethyl-containing pyrazolinyl (p-tolyl) sulphpones: The synthesis and structure of promising antimicrobial agents. J. Fluor. Chem., 127: 1066-1072. CrossRef |
Boyd, M.R. and K.D. Paull, 1995. Some practical considerations and applications of the national cancer institute in vitro anticancer drug discovery screen. Drug Dev. Res., 34: 91-109. CrossRef | Direct Link |
Elgeuro, J., 1984. Comprehensive Heterocyclic Chemistry. Pergamon Press, New York, pp: 291
Filler, R. and Y. Kabayashi, 1992. Biomedicinal Aspects of Fluorine Chemistry. Elsevier, Amsterdam, UK
Olla, B.S., K.V. Udupa and K.R. Sridhar, 1989. The reaction of acetylenic ketones with aroylhydrazines. Bull. Chem. Soc. Jap., 62: 3409-3411.
Holla, B.S., M. Mahalinga, M. Ashok and P. Karegoudar, 2006. Convenient synthesis of some 4' methtylthio containing aryl and arylfuryl pyrazolines and their antimicrobial activity studies. Phosphorus Sulfur Silicon Related Elements, 181: 1427-1436. Direct Link |
Holla, B.S., M. Mahalinga, M.S. Karthikeyan, P.M. Akberali and N.S. Shetty, 2006. Synthesis of some novel pyrazolo [3,4-d] pyrimidine derivatives as potential antimicrobial agents. Bioorg. Med. Chem., 14: 2040-2047. Direct Link |
Holla, B.S., M. Mahalinga, B. Poojary, M. Ashok and P.M. Akberali, 2006. Synthesis of pyrazolines promoted by amberlyst 15 catalyst. Ind. J. Chem. Section B Org. Med. Chem., 45: 568-571. Direct Link |
Karthikeyan, M.S., B.S. Holla and N.S. Kumari, 2007. Synthesis and antimicrobial studies on novel chloro-fluorine containing hydroxy pyrazolines. Eur. J. Med. Chem., 42: 30-36. Direct Link |
Nowakowska, Z., 2007. A review of anti-infective and anti-inflammatory chalcones. Eur. J. Med. Chem., 42: 125-137. Direct Link |
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