Skip to main content

Synthesis of new pyrazolyl-2, 4-thiazolidinediones as antibacterial and antifungal agents

Abstract

Background

Thiazolidine-2, 4-diones (TZDs) have become a pharmacologically important class of heterocyclic compounds since their introduction in the form of glitazones into the clinical use for the treatment of type 2 diabetes. TZDs lower the plasma glucose levels by acting as ligands for gamma peroxisome proliferators-activated receptors. In addition, this class of heterocyclic compounds possesses various other biological activities such as antihyperglycemic, antimicrobial, anti-inflammatory, anticonvulsant, insecticidal, etc. TZDs are also known for lowering the blood pressure thereby reducing the chances of heart failure and micro-albuminuria in the patients with type 2 diabetes.

Results

We have described herein the synthesis of three series of compounds, namely, ethyl 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetates (4), methyl 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetates (5), and 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acids (6). The compounds 4 and 5 were synthesized by Knoevenagel condensation between 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes (1) and ethyl/methyl 2-(2, 4-dioxothiazolidin-3-yl)acetates (3, 2) in alcohol using piperidine as a catalyst. The resultant compounds 4 and 5 having ester functionality were subjected to acidic hydrolysis to obtain 6. All the new compounds were tested for their in vitro antibacterial and antifungal activity.

Conclusions

Knoevenagel condensation approach has offered an easy access to new compounds 4-6. Antimicrobial evaluation of the compounds has shown that some of the compounds are associated with remarkable antifungal activity. In case of antibacterial activity, these were found to be effective against Gram-positive bacteria. However, none of the compounds were found to be effective against Gram-negative bacteria.

1. Background

Natural antibiotic compounds have become essential to current health care system, assisting and complementing the natural immune system against microbial pathogens. As conventional antibiotics are often abused to treat microbial infections, some microorganisms have developed tolerance to these antibiotics. Because of the appearance of antibiotic-resistant strains, the continuous development of novel efficient antibiotic agents is more crucial than ever [1–3]. So, the medical community faces a serious problem against infections caused by the pathogen bacteria and needs an effective therapy and search for novel antimicrobial agents. Synthetic organic chemistry has always been a vital part of highly integrated and multidisciplinary process of various drug developments. In this context, this study was designed to evaluate antimicrobial properties of new pyrazole derivatives containing thiazolidindiones.

Pyrazole derivatives are known to possess wide spectrum of pharmacological properties such as antibacterial [4–6], antifungal [7–9], antimicrobial [10–14], antidiabetic [15], herbicidal [16, 17], antitumor [18–21], anti-anxiety [22], and as active pharmacophore in celecoxib (as COX-2 inhibitor) [23] and slidenafil citrate [24] (as cGMP specific phosphodiesterase type 5 inhibitor), etc. Pyrazoles play an essential role in biological active compounds and therefore represent an interesting template for medicinal chemistry.

On the other hand, thiazolidines are also known for their potential biological activities. The varied biological activities of rhodanines (2-thioxo-thiazolidin-4-one) and their analogs have been known from the beginning of twentieth century. Rhodanines and 2, 4-thiazolidinediones (TZDs) have become a pharmacologically important class of heterocyclic compounds since the introduction of various glitazone and epalrestat into clinical use for the treatment of type II diabetes and diabetic complications [25]. Several studies have been reported that TZDs have acquired much importance because of their diverse pharmaceutical applications such as antihyperglycemic [26], bactericidal [27], pesticidal [28], fungicidal [29], insecticidal [30], anticonvulsant [31], tuberculostatic [32], anti-inflammatory [33] etc.

Different possibilities of heterocyclic modifications with a wide spectrum of pharmacological propertiesare the most important grounds for investigation of this class of compounds. There have been many reports in literature depicting that the presence of heterocyclic moieties such as thiazole, pyrazole, flavone, chromone, sultam, and furan at fifth position proves to be more potent and efficacious than a simple aryl group [34–39]. Although there are not many TZDs fused to pyrazoles, a number of them are incorporated into a wide variety of therapeutically important compounds possessing a broad spectrum of biological activities. In a recent article, pyrazolyl-2, 4-TZDs have been reported as anti-inflammatory and neuroprotective agents.

Motivated by these findings and in continuation of our ongoing efforts endowed with the discovery of nitrogen-containing heterocycles with potential chemotherapeutic activities [8, 10, 40–44], we disclose here the synthesis and investigations of antimicrobial activities of new pyrazolyl-2, 4-TZD.

2. Results and discussion

2.1. Chemistry

The synthetic route for the preparation of ethyl 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetates (4a-h), methyl 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetates (5a-h), and 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acids (6a-h) has been illustrated in Scheme 1. Initially, Knoevenagel condensation was carried out with equimolar ratio of ethyl 2-(2, 4-dioxothiazolidin-3-yl)acetate (3) and 1, 3-diphenyl-1H-pyrazole-4-carbaldehyde (1a) in ethanol in presence of catalytic amount of piperidine by refluxing for 5-6 h. The usual work up of the reaction afforded the single product, ethyl 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (4a) as yellow solid in 90% yield. Similar method was adopted for the preparation of 5a in methanol. The acid hydrolysis of 4a or 5a in acetic acid in the presence of dilute sulfuric acid under refluxing for 5-6 h gave the desired product 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetic acid (6a) in 94% yield.

Scheme 1
scheme 1

Synthesis of pyrazolyl-2, 4-TZDs (4-6).

All other compounds 4b-h, 5b-h, and 6b-h were prepared adopting the similar methodology. The physical data of all compounds 4-6 have been summarized in Table 1.

Table 1 Physical data of the compounds 4-6

The structures of all compounds 4a-h, 5a-h, and 6a-h were established by the spectral (IR, NMR {see additional files 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 and 24}, Mass) and elemental analysis. For example, IR spectrum of the compound 4a exhibited characteristic absorption bands at 1736 and 1690 cm-1 because of carbonyl groups of ester and TZD. The 1H NMR spectrum of the product 4a (see additional files 1) showed three characteristic singlets at δ 8.213, δ 7.963, and δ 4.473 because of C(5)-H of pyrazole ring, =CH and -NCH2, respectively, apart from other aromatic signals. Besides these the aliphatic region also showed the characteristic quartet and triplet due to -OCH2CH3 at δ 4.248 and δ 1.301, respectively. The product 6a was characterized by careful comparison of the IR and 1H NMR spectra (see additional file 17) with those of the 4a. An important characteristic feature in 1H NMR spectrum of 6a was disappearance of the triplet and quartet in the aliphatic region which was present in the spectrum of 4a.

The starting materials 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes (1a-h) were prepared according to literature procedure involving Vilsmeier-Haack reaction of various substituted acetophenone hydrazones using POCl3/DMF at 50-60°C for 4-5 h [45–47] and ethyl/methyl 2-(2, 4-dioxothiazolidin-3-yl)acetates (3, 2) were prepared in multiple steps by alkylation of potassium salt of thiazolidine-2, 4-dione (TZDs) with appropriate alkyl 2-bromoacetate either in acetone at 50°C for 5 h or in KI/DMF at 90°C for 12 h [48]. The key starting material 2, 4-TZD needed for this purpose was obtained in one step from equimolar amounts of chloroacetic acid and thiourea under ice cold condition. The white precipitate of 2-imino thiazolidine-4-one obtained was then acidified and refluxed with HCl for 12 h to get white crystals of 2, 4-TZD [49].

Although geometrical isomerism (E/Z isomers) was possible because of restricted rotation about the exocyclic C=C bond of the pyrazolyl-2, 4-TZDs, all the derivatives prepared in this study were obtained exclusively in Z-form as confirmed by the analytical data. The 1H NMR spectra of the pyrazolyl-2, 4-TZDs (see additional files 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24) showed that the most characteristic olefinic proton =CH was deshielded more (δ = 7.3-7.6 ppm) as expected in Z-form, relative to the slightly shielded protons of the E-form (δ = 6.2-6.3 ppm, in case of various other arylidene-2, 4-TZD). This deshielding of the olefinic proton is caused by the anisotropic effect exerted by the nearby carbonyl group of the 2, 4-TZDs in Z-isomer. Furthermore, the Z-isomers are thermodynamic more stable because of intramolecular hydrogen bond that can be formed between the hydrogen bond of =CH and oxygen atom in TZD [50, 51].

2.2. Pharmacology

2.2.1. In vitro antifungal activity

All the 24 compounds were tested for their in vitro antifungal activity against two fungi, namely, Aspergillus niger and Aspergillus flavus. Standard antibiotic, namely, Fluconazole, was used for comparison with antifungal activity shown by compounds 4a-h, 5a-h, and 6a-h. A careful analysis of percentage mycelial growth inhibition revealed that almost all the newly synthesized compounds showed comparable antifungal activity with commercial antibiotics Fluconazole as shown in Table 2.

Table 2 In vitro antifungal activity of the compounds 4-6

Compounds 4b and 4e showed maximum inhibition against A. niger (70%) and A. flavus (67.7%), respectively. Eleven compounds 4d, 4e, 4g, 5a, 5h, 6a, 6b, 6d, 6e, 6f, and 6h showed more than 60% inhibition against A. flavus in comparison to 77.7% of Fluconazole. Eleven compounds which showed more than 60% inhibition against A. niger are 4b, 4d, 4e, 4h, 5c, 5d, 6a, 6b, 6d, 6e, 6f. After all, the compounds which showed more than 60% inhibition against both the pathogenic fungi are 4a, 4e, 6a, 6d, and 6e.

2.2.2. In vitro antibacterial activity

All the 24 compounds 4a-h, 5a-h, and 6a-h were tested in vitro for their antibacterial activity against two Gram-positive bacteria, namely, Staphylococcus aureus (MTCC 96), Bacillus subtillis (MTCC 121) and two Gram-negative bacteria, namely, Escherichia coli (MTCC 1652), and Pseudomonas aeruginosa (MTCC 741) (Tables 3 and 4). Minimum inhibitory concentrations (MIC) of those compounds were determined which were showing activity in primary screening. Standard antibiotic, Ciprofloxacin, was used for comparison with antibacterial activity shown by the compounds 4a-h, 5a-h, and 6a-h.

Table 3 In vitro antibacterial activity of the compounds 4-6
Table 4 MIC of the compounds 4-6

All compounds of the tested series showed variable antibacterial activity against Gram-positive bacteria. Three of the tested compounds 5h, 6a, and 6h exhibited good antibacterial activity against Gram-positive bacteria. However, none of the compounds showed activity against Gram-negative bacteria.

In case of Gram-positive bacteria, compounds 4h, 5b, 5h, 6a, 6b, and 6h were found to be most effective against S. aureus with zone of inhibition ranging between 18.6 mm and 20.0 mm and the compounds 5h, 6a, and 6b were most effective against B. subtillis with zone of inhibition ranging between 19.3 mm and 21.0 mm (Table 3).

In whole series, compounds 4a, 4h, and 5h showed maximum antibacterial activity against S. aureus (MIC 64 μg/mL) and compounds 5h (MIC 32 μg/mL), 6a & 6h (MIC 64 μg/mL) against B. subtillis (Table 4).

3. Conclusions

We have described herein an efficient and convenient synthesis of three series of pyrazolyl-2, 4-TZDs (4-6) by Knoevenagel condensation. All the 24 compounds synthesized were characterized by spectral and elemental analytical data and evaluated for their in vitro antifungal and antibacterial activities. Results of the antifungal activity were found to be comparable with the reference compound. On the other hand, antibacterial activity was best observed for Gram-positive bacteria only, none of the compounds showed activity against Gram-negative bacteria.

4. Experimental

4.1. General remarks

Melting points (mps) were taken on slides in an electrical apparatus Labindia visual melting range apparatus and are uncorrected. Calibration of melting point apparatus was done using benzoic acid as reference. IR spectra were recorded on a Perkin-Elmer 1800 FT-IR spectrophotometer. 1H NMR spectra (see additional files 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24) were recorded on a Bruker 300 & 400 MHz instrument using tetramethylsilane as an internal standard. Mass spectra were recorded on 2500 eV (ESI Source) using a water's Q-TOF microinstrument and elemental analysis on Perkin-Elmer 2400 instrument. All the reagents were purchased from the commercial sources and were used without further purification.

4.2. Preparation of ethyl 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetates (4a-h)

Typical procedure: A mixture of 1, 3-diphenyl-1H-pyrazol-4-carboxaldehyde 1a (0.5 g, 2 mmol) and ethyl 2-(2, 4-dioxothiazolidin-3-yl)acetate 3 (0.4 g, 2 mmol) in ethanol (20 mL) and 2-3 drops of piperidine was refluxed for 4-5 h. A solid was separated out of the reaction mixture within 15-20 min and the refluxing was continued for 4-5 h to complete the reaction. The reaction mixture was cooled to room temperature, filtered, and washed with ethanol to give the pure product 4a (0.87 g, 90% yield).

The other derivatives 4b-h were synthesized by adopting the similar procedure.

4.3. Ethyl 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (4a)

IR (νmax, KBr) cm-1: 1736, 1690, 1612, 1535, 1504, 1450, 1373, 1311, 1227, 1142, 1103, 1065, 1026. 1H NMR (CDCl3, 400 MHz, δ): 8.213 (s, 1H, Pyrazolyl H), 7.963 (s, 1H, =CH), 7.817-7.795 (m, 2H, Ar H), 7.678-7.654 (m, 2H, Ar H), 7.549-7.471 (m, 5H, Ar H), 7.414-7.377 (m, 1H, Ar H), 4.473 (s, 2H, NCH2), 4.275-4.222 (q, 2H, -OCH2CH3), 1.319-1.283 (t, 3H, -OCH2CH3). MS (ESI+) m/z 434 [M+H]. Anal. Found: C, 63.3; H, 4.6; N, 9.5. C23H19N3O4S requires C, 63.73; H, 4.42; N, 9.69%.

4.4. Ethyl 2-((Z)-2, 4-dioxo-5-((1-phenyl-3-p-tolyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (4b)

IR (νmax, KBr) cm-1: 1736, 1690, 1605, 1520, 1450, 1373, 1311, 1219, 1142, 1095, 1026. 1H NMR (DMSO-d6, 400 MHz, δ): 8.812 (s, 1H, Pyrazolyl H), 8.041-8.022 (m, 2H, Ar H), 7.739 (s, 1H, =CH) 7.598-7.536 (m, 4H, Ar H), 7.448-7.379 (m, 3H, Ar H), 4.480 (s, 2H, NCH2), 4.199-4.145 (q, 2H, -OCH2CH3), 2.405 (s, 3H, Ph CH3), 1.231-1.195 (t, 3H, -OCH2CH3). MS (ESI+) m/z 448 [M+H]. Anal. Found: C, 64.0; H, 4.98; N, 9.2. C24H21N3O4S requires C, 64.41; H, 4.73, N, 9.39%.

4.5. Ethyl 2-((Z)-5-((3-(4-methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (4c)

IR (νmax, KBr) cm-1: 1736, 1690, 1612, 1520, 1450, 1373, 1311, 1296, 1227, 1180, 1142, 1095, 1026, 1018. 1H NMR (TFA-d1, 400 MHz, δ): 8.483 (s, 1H, Pyrazolyl H), 7.917 (s, 1H, =CH), 7.667-7.583 (m, 7H, Ar H), 7.179-7.157 (d, 2H, Ar H, J = 8.8 Hz), 4.620 (s, 2H, NCH2), 4.345-4.291 (q, 2H, CH2CH3), 3.922 (s, 3H, Ph OCH3), 1.304-1.269 (t, 3H, CH3CH2). MS (ESI+) m/z 464 [M+H]. Anal. Found: C, 61.8; H, 4.1; N, 8.6. C24H21N3O5S requires C, 62.19; H, 4.57; N, 9.07%.

4.6. Ethyl 2-((Z)-5-((3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (4d)

IR (νmax, KBr) cm-1: 1736, 1690, 1612, 1528, 1443, 1373, 1311, 1227, 1142, 1095, 1011. 1H NMR (TFA-d1, 400 MHz, δ): 8.657 (s, 1H, Pyrazolyl H), 8.052 (s, 1H, =CH), 7.832-7.748 (m, 5H, Ar H), 7.748-7.724 (m, 4H, Ar H), 4.789 (s, 2H, NCH2), 4.515-4.462 (q, 2H, -OCH2CH3), 1.476-1.440 (t, 3H, -OCH2CH3). MS (ESI+) m/z 454 [M+H]. Anal. Found: C, 58.6; H, 3.9; N, 8.7. C23H18ClN3O4S requires C, 59.04; H, 3.88; N, 8.98%.

4.7. Ethyl 2-((Z)-5-((3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (4e)

IR (νmax, KBr) cm-1: 1736, 1697, 1612, 1512, 1450, 1373, 1311, 1234, 1142, 1095, 1026. 1H NMR (TFA-d1, 400 MHz, δ): 8.489 (s, 1H, Pyrazolyl H), 7.884 (s, 1H, =CH), 7.652-7.584 (m, 7H, Ar H), 7.290-7.247 (m, 2H, Ar H), 4.624 (s, 2H, NCH2), 4.351-4.297 (q, 2H, -OCH2CH3), 1.311-1.275 (t, 3H, -OCH2CH3). MS (ESI+) m/z 437 [M+H]. Anal. Found: C, 61.0; H, 4.2; N, 9.2. C23H18FN3O4S requires C, 61.19; H, 4.02; N, 9.31%.

4.8. Ethyl 2-((Z)-5-((3-(4-bromophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (4f)

IR (νmax, KBr) cm-1: 1736, 1690, 1605, 1528, 1443, 1373, 1311, 1227, 1142, 1095, 1003. 1H NMR (TFA-d1, 400 MHz, δ): 8.488 (s, 1H, Pyrazolyl H), 7.896 (s, 1H, =CH), 7.750-7.729 (m, 2H, Ar H), 7.650-7.588 (m, 5H, Ar H), 7.489-7.467 (d, 2H, Ar H, J = 8.8 Hz) 4.633 (s, 2H, NCH2), 4.359-4.305 (q, 2H, -OCH2CH3), 1.319-1.283 (t, 3H, -OCH2CH3). MS (ESI+) m/z 497 [M+H]. Anal. Found: C, 53.7; H, 3.4; N, 8.0. C23H18BrN3O4S requires C, 53.91; H, 3.54; N, 8.20%.

4.9. Ethyl 2-((Z)-5-((3-(4-hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (4g)

IR (νmax, KBr) cm-1: 3387, 1736, 1682, 1605, 1520, 1373, 1319, 1234, 1142, 1103, 1026. 1H NMR (DMSO-d6, 400 MHz, δ): 9.850 (bs, 1H, OH), 8.773 (s, 1H, Pyrazolyl H), 8.027-8.007 (m, 2H, Ar H), 7.734 (s, 1H, =CH), 7.588-7.549 (m, 2H, Ar H), 7.474-7.452 (d, 2H, Ar H, J = 8.8 Hz), 7.435-7.398 (m, 1H, Ar H), 6.955-6.933 (d, 2H, Ar H, J = 8.8 Hz), 4.479 (s, 2H, NCH2), 4.199-4.146 (q, 2H, -OCH2CH3), 1.232-1.196 (t, 3H, -OCH2CH3). MS (ESI+) m/z 435 [M+H]. Anal. Found: C, 61.3; H, 4.4; N, 9.1. C23H19N3O5S requires C, 61.46; H, 4.26; N, 9.35%.

4.10. Ethyl 2-((Z)-5-((3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (4h)

IR (νmax, KBr) cm-1: 1736, 1697, 1620, 1528, 1350, 1319, 1234, 1142, 1095. 1H NMR (TFA-d1, 400 MHz, δ): 8.482-8.460 (d, 2H, Ar H, J = 8.8 Hz), 8.391 (s, 1H, Pyrazolyl H), 7.957 (s, 1H, =CH), 7.895-7.874 (d, 2H, Ar H, J = 8.4 Hz), 7.664-7.652 (m, 2H, Ar H), 7.586-7.573 (m, 3H, Ar H), 4.666 (s, 2H, NCH2), 4.388-4.334 (q, 2H, -OCH2CH3), 1.347-1.311 (t, 3H, -OCH2CH3). MS (ESI+) m/z 465 [M+H]. Anal. Found: C, 57.4; H, 3.9; N, 11.6. C23H18N4O6S requires C, 57.73; H, 3.79; N, 11.71%.

4.11. Preparation of methyl 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetates (5a-h)

Typical procedure: A mixture of 1, 3-diphenyl-1H-pyrazol-4-carboxaldehyde 1a (0.5 g, 2 mmol) and methyl 2-(2, 4-dioxothiazolidin-3-yl)acetate 2 (0.38 g, 2 mmol) in methanol (20 ml) and 2-3 drops of piperidine was refluxed 4-5 h. A solid was separated out of the reaction mixture within 15-20 min and the refluxing was continued for 4-5 h to complete the reaction. The reaction mixture was cooled to room temperature, filtered and washed with methanol to give the pure product 5a (0.84 g, 92% yield).

The other derivatives 5b-h were synthesized by adopting the similar procedure.

4.12. Methyl 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (5a)

IR (νmax, KBr) cm-1: 1744, 1690, 1605, 1535, 1443, 1366, 1311, 1234, 1142, 1103, 1011. 1H NMR (DMSO-d6, 400 MHz, δ): 8.828 (s, 1H, Pyrazolyl H), 8.069-8.029 (m, 2H, Ar H), 7.745 (s, 1H, =CH), 7.685-7.649 (m, 2H, Ar H), 7.601-7.537 (m, 5H, Ar H), 7.453-7.417 (m, 1H, Ar H), 4.501 (s, 2H, NCH2), 3.711 (s, 3H, COOCH3). MS (ESI+) m/z 406 [M+H]. Anal. Found: C, 62.7; H, 4.2; N, 9.9. C22H17N3O4S requires C, 63.00; H, 4.09; N, 10.02%.

4.13. Methyl 2-((Z)-2, 4-dioxo-5-((1-phenyl-3-p-tolyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (5b)

IR (νmax, KBr) cm-1: 1744, 1690, 1605, 1512, 1443, 1366, 1319, 1234, 1142, 1103, 1011. 1H NMR (TFA-d1, 400 MHz, δ): 8.501 (s, 1H, Pyrazolyl H), 7.924 (s, 1H, =CH), 7.626 (m, 5H, Ar H), 7.492-7.472 (m, 2H, Ar H), 7.417-7.398 (m, 2H, Ar H), 4.632 (s, 2H, NCH2), 3.711 (s, 3H, COOCH3), 2.404 (s, 3H, Ph CH3). MS (ESI+) m/z 419 [M+H]. Anal. Found: C, 63.6; H, 4.5; N, 9.4. C23H19N3O4S requires C, 63.73; H, 4.42; N, 9.69%.

4.14. Methyl 2-((Z)-5-((3-(4-methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (5c)

IR (νmax, KBr) cm-1: 1744, 1690, 1612, 1520, 1443, 1366, 1296, 1242, 1180, 1142, 1103, 1018. 1H NMR (TFA-d1, 400 MHz, δ): 8.477 (s, 1H, Pyrazolyl H), 7.915 (s, 1H, =CH), 7.665-7.568 (m, 6H, Ar H), 7.178-7.156 (d, 2H, Ar H, J = 8.8 Hz), 4.630 (s, 2H, NCH2), 3.923 (s, 3H, COOCH3), 3.859 (s, 3H, Ph OCH3). MS (ESI+) m/z 436 [M+H]. Anal. Found: C, 61.3; H, 4.4; N, 9.2. C23H19N3O5S requires C, 61.46; H, 4.26; N, 9.35%.

4.15. Methyl 2-((Z)-5-((3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (5d)

IR (νmax, KBr) cm-1: 1744, 1697, 1605, 1528, 1443, 1366, 1319, 1242, 1142, 1103, 1011. 1H NMR (TFA-d1, 400 MHz, δ): 8.476 (s, 1H, Pyrazolyl H), 7.884 (s, 1H, =CH), 7.618-7.552 (m, 9H, Ar H), 4.630 (s, 2H, NCH2), 3.861 (s, 3H, COOCH3). MS (ESI+) m/z 440 [M+H]. Anal. Found: C, 58.0; H, 3.6; N, 9.1. C22H16N3O4S requires C, 58.21; H, 3.55; N, 9.26%.

Methyl 2-((Z)-5-((3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (5e)

IR (νmax, KBr) cm-1: 1744, 1697, 1612, 1520, 1404, 1366, 1319, 1234, 1149, 1095. 1H NMR (TFA-d1, 400 MHz, δ): 8.494 (s, 1H, Pyrazolyl H), 7.893 (s, 1H, =CH), 7.650-7.616 (m, 7H, Ar H), 7.300-7.258 (m, 2H, Ar H), 4.663 (s, 2H, NCH2), 3.876 (s, 3H, COOCH3). MS (ESI+) m/z 424 [M+H]. Anal. Found: C, 60.2; H, 3.8; N, 9.5. C22H16FN3O4S requires C, 60.40; H, 3.69; N, 9.61%.

Methyl 2-((Z)-5-((3-(4-bromophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (5f)

IR (νmax, KBr) cm-1: 1744, 1697, 1612, 1520, 1404, 1366, 1319, 1234, 1149, 1095. 1H NMR (CDCl3 + TFA-d1, 400 MHz, δ): 8.250 (s, 1H, Pyrazolyl H), 7.899 (s, 1H, =CH), 7.750-7.730 (d, 2H, Ar H, J = 8.0 Hz), 7.660-7.611 (m, 5H, Ar H), 7.500-7.480 (d, 2H, Ar H, J = 8.00 Hz), 4.652 (s, 2H, NCH2), 3.901 (s, 3H, COOCH3). MS (ESI+) m/z 483 [M+H]. Anal. Found: C, 52.9; H, 3.4; N, 8.2. C22H16BrN3O4S requires C, 53.02; H, 3.24; N, 8.43%.

Methyl 2-((Z)-5-((3-(4-hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (5g)

IR (νmax, KBr) cm-1: 3348, 1736, 1682, 1605, 1512, 1443, 1412, 1373, 1311, 1234, 1211, 1142, 1103. 1H NMR (DMSO-d6, 400 MHz, δ): 9.863 (s, 1H, Ph OH), 8.764 (s, 1H, Pyrazolyl H), 8.023-8.003 (m, 2H, Ar H), 7.730 (s, 1H, =CH), 7.585-7.546 (m, 2H, Ar H), 7.471-7.450 (d, 2H, Ar H, J = 8.4 Hz), 7.434-7.395 (m, 1H, Ar H), 6.954-6.933 (d, 2H, Ar H, J = 8.4 Hz), 4.499 (s, 2H, NCH2), 3.712 (s, 3H, COOCH3). MS (ESI+) m/z 450 [M+H]. Anal. Found: C, 60.5; H, 4.0; N, 9.5. C22H17N3O5S requires C, 60.68; H, 3.93; N, 9.65%.

Methyl 2-((Z)-5-((3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (5h)

IR (νmax, KBr) cm-1: 1744, 1690, 1605, 1528, 1412, 1342, 1273, 1219, 1142, 1103. 1H NMR (CDCl3 + TFA-d1, 400 MHz, δ): 8.454-8.434 (d, 2H, Ar H, J = 8.8 Hz), 8.261-8.247 (m, 2H, Ar H), 7.906-7.834 (m, 3H, Ar H), 7.710-7.689 (m, 2H, Ar H), 7.637-7.571 (m, 2H, Ar H), 4.642 (s, 2H, NCH2), 3.985 (s, 3H, COOCH3). MS (ESI+) m/z 450 [M+H]. Anal. Found: C, 58.7; H, 3.6; N, 11.8. C22H16N4O6S requires C, 58.89; H, 3.47; N, 12.06%.

Preparation of 2-((Z)-5-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6a-h)

Typical procedure: A mixture of ethyl 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate 4a (0.5g, 1.1 mmol), 10 mL of 50% aqueous sulphuric acid in 35 mL acetic acid was refluxed for 5-6 h. On cooling, the reaction mixture was poured onto crushed ice. Solid separated was filtered, washed with excess of cold water followed by alcohol to obtain white solid 6a (0.47g, 94%). Similarly, 6a can also be obtained from 5a by hydrolysis.

All other derivatives 6b-h were synthesized by adopting the similar procedure.

2-((Z)-2, 4-Dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetic acid (6a)

IR (νmax, KBr) cm-1: 3472, 3418, 1744, 1697, 1605, 1528, 1504, 1443, 1373, 1319, 1219, 1149, 1103, 1102, 1057, 1003. 1H NMR (DMSO-d6, 300 MHz, δ): 8.807 (s, 1H, Pyrazolyl H), 8.040-8.018 (m, 2H, Ar H), 7.729-7.434 (m, 9H, ArH + =CH), 4.359 (s, 2H, NCH2). MS (ESI+) m/z 392 [M+H]. Anal. Found: C, 62.1; H, 3.8; N, 10.2. C21H15N3O4S requires C, 62.21; H, 3.73; N, 10.36%.

2-((Z)-2, 4-Dioxo-5-((1-phenyl-3-p-tolyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetic acid (6b)

IR (νmax, KBr) cm-1: 1744, 1697, 1605, 1512, 1450, 1389, 1319, 1227, 1149, 1103, 1003. 1H NMR (DMSO-d6, 300 MHz, δ): 8.795 (s, 1H, Pyrazolyl H), 8.045-8.015 (m, 2H, Ar H), 7.727 (s, 1H, =CH), 7.603-7.530 (m, 4H, Ar H), 7.451-7.373 (m, 3H, Ar H), 4.366 (s, 2H, NCH2), 2.405 (s, 3H, CH3). MS (ESI+) m/z 406 [M+H]. Anal. Found: C, 62.8; H, 4.2; N, 9.9. C22H17N3O4S requires C, 63.00; H, 4.09; N, 10.02%.

2-((Z)-5-((3-(4-Methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6c)

IR (νmax, KBr) cm-1: 1736, 1690, 1612, 1520, 1450, 1396, 1296, 1242, 1180, 1142, 1103, 1018. 1H NMR (DMSO-d6, 300 MHz, δ): 8.782 (s, 1H, Pyrazolyl H), 8.037-8.011 (m, 2H, Ar H), 7.722 (s, 1H, =CH), 7.599-7.548 (m, 4H, Ar H), 7.447-7.398 (m, 1H, Ar H), 7.149-7.120 (d, 2H, Ar H, J = 8.7 Hz), 4.365 (s, 2H, NCH2), 3.842 (s, 3H, OCH3). MS (ESI+) m/z 422 [M+H]. Anal. Found: C, 60.5; H, 3.8, N, 14.20. C22H17N3O5S requires C, 60.68; H, 3.93; N, 9.65%.

2-((Z)-5-((3-(4-Chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6d)

IR (νmax, KBr) cm-1: 3472, 3418, 1736, 1690, 1612, 1520, 1450, 1396, 1296, 1242, 1180, 1142, 1103, 1018. 1H NMR (DMSO-d6, 300 MHz, δ): 8.776 (s, 1H, Pyrazolyl H), 8.006-7.980 (d, 2H, Ar H, J = 7.8 Hz), 7.687 (s, 1H, =CH), 7.656-7.544 (m, 6H, Ar H), 7.449-7.365 (m, 1H, Ar H), 4.350 (s, 2H, NCH2). MS (ESI+) m/z 426 [M+H]. Anal. Found: C, 57.0; H, 3.4; N, 9.4. C21H14ClN3O4S requires C, 57.34; H, 3.21; N, 9.55%.

2-((Z)-5-((3-(4-Fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6e)

IR (νmax, KBr) cm-1: 1751, 1697, 1612, 1512, 1450, 1373, 1319, 1227, 1149, 1095, 1003. 1H NMR (DMSO-d6, 300 MHz, δ): 8.819 (s, 1H, Pyrazolyl H), 8.048-8.022 (d, 2H, Ar H, J = 7.8 Hz), 7.737-7.711 (m, 3H, =CH and Ar H), 7.607-7.556 (m, 2H, Ar H), 7.455-7.396 (m, 3H, Ar H), 4.369 (s, 2H, NCH2). MS (ESI+) m/z 410 [M+H]. Anal. Found: C, 59.4; H, 3.5; N, 9.8. C21H14FN3O4S requires C, 59.57; H, 3.33; N, 9.92%.

2-((Z)-5-((3-(4-Bromophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6f)

IR (νmax, KBr) cm-1: 1744, 1697, 1605, 1528, 1504, 1443, 1389, 1319, 1242, 1149, 1103, 1003. 1H NMR (DMSO-d6, 300 MHz, δ): 8.822 (s, 1H, Pyrazolyl H), 8.039-8.013 (m, 2H, Ar H), 7.798-7.771 (d, 2H, Ar H, J = 8.1 Hz), 7.712 (s, 1H, =CH), 7.634-7.607 (d, 2H, Ar H, J = 8.1 Hz), 7.581-7.555 (m, 2H, Ar H), 7.460-7.413 (m, 1H, Ar H), 4.372 (s, 2H, NCH2). MS (ESI+) m/z 470 [M+H]. Anal. Found: C, 51.9; H, 2.8; N, 8.5. C21H14BrN3O4S requires C, 52.08; H, 2.91; N, 8.68%.

2-((Z)-5-((3-(4-Hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6g)

IR (νmax, KBr) cm-1: 3379, 3310, 1736, 1713, 1674, 1605, 1512, 1443, 1404, 1373, 1219, 1142, 1103, 1057, 1003. 1H NMR (DMSO-d6, 300 MHz, δ): 9.886 (bs, 1H, Ph OH), 8.753 (s, 1H, Pyrazolyl H), 8.026-8.000 (d, 2H, Ar H, J = 7.8 Hz), 7.721 (s, 1H, =CH), 7.591-7.540 (m, 2H, Ar H), 7.476-7.388 (m, 3H, Ar H), 6.960-6.933 (d, 2H, Ar H, J = 8.1 Hz), 4.361 (s, 2H, NCH2). MS (ESI+) m/z 408 [M+H]. Anal. Found: C, 59.7; H, 3.7; N, 9.8. C21H15N3O5S requires C, 59.85; H, 3.59; N, 9.97%.

2-((Z)-5-((3-(4-Nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (6h)

IR (νmax, KBr) cm-1: 3418, 3479, 1774, 1728, 1674, 1605, 1528, 1404, 1350, 1242, 1180, 1142, 1103 1065. 1H NMR (DMSO-d6, 300 MHz, δ): 8.887 (s, 1H, Pyrazolyl H), 8.433-8.404 (d, 2H, Ar H, J = 8.7 Hz), 8.066-8.039 (d, 2H, Ar H, J = 8.1 Hz), 7.983-7.954 (d, 2H, Ar H, J = 8.7 Hz), 7.763 (s, 1H, =CH), 7.622-7.571 (m, 2H, Ar H), 7.482-7.434 (m, 1H, Ar H), 4.384 (s, 2H, NCH2). MS (ESI+) m/z 451 [M+H]. Anal. Found: C, 55.8; H, 3.0; N, 12.3. C21H14N4O6S requires C, 56.00; H, 3.13; N, 12.44%.

Biological assay

Test microorganisms

Four bacteria, S. aureus (MTCC 96), B. subtilis (MTCC 121) (Gram-positive), E. coli (MTCC 1652) and P. aeruginosa (MTCC 741) (Gram-negative) procured from MTCC, Chandigarh and two fungi, A. niger and A. flavus, the ear pathogens isolated from the Kurukshetra patients, were used in this study [52].

In vitro antibacterial activity

The antibacterial activity of synthesized compounds was evaluated by the agar well-diffusion method. All the cultures were adjusted to 0.5 McFarland standard, which is visually comparable to a microbial suspension of approximately 1.5 × 108 cfu/mL. 20-mL of Mueller Hinton agar medium was poured into each Petri plate and the agar plates were swabbed with 100 μL inocula of each test bacterium and kept for 15 min for adsorption. Using sterile cork borer of 8-mm diameter, wells were bored into the seeded agar plates and these were loaded with a 100-μL volume with concentration of 4.0 mg/mL of each compound reconstituted in the dimethylsulphoxide (DMSO). All the plates were incubated at 37°C for 24 h. Antibacterial activity of each synthetic compound was evaluated by measuring the zone of growth inhibition against the test organisms with zone reader (Hi Antibiotic zone scale). DMSO was used as a negative control whereas ciprofloxacin was used as a positive control. This procedure was performed in three replicate plates for each organism [53].

Determination of MIC

MIC is the lowest concentration of an antimicrobial compound that will inhibit the visible growth of a microorganism after overnight incubation. MIC of the various compounds against bacterial strains was tested through a macro dilution tube method as recommended by NCCLS [54]. In this method, various test concentrations of synthesized compounds were made from 128 to 0.25 μg/mL in sterile tubes no. 1 to 10. 100-μL sterile Mueller Hinton Broth (MHB) was poured in each sterile tube followed by addition of 200 μL test compound in tube 1. Twofold serial dilutions were carried out from the tube no. 1 to the tube no. 10 and excess broth (100 μL) was discarded from the last tube no. 10. To each tube, 100 μL of standard inoculums (1.5 × 108 cfu/mL) was added. Ciprofloxacin was used as control. Turbidity was observed after incubating the inoculated tubes at 37°C for 24 h.

In vitro antifungal activity

The antifungal activity of the synthesized compounds was evaluated by poisoned food technique. The molds were grown on Sabouraud dextrose agar (SDA) at 25°C for 7 days and used as inocula. 15 mL of molten SDA (45°C) was poisoned by the addition of 100 μL volume of each compound having concentration of 4.0 mg/mL, reconstituted in the DMSO, poured into a sterile Petri plate and allowed it to solidify at room temperature. The solidified poisoned agar plates were inoculated at the centre with fungal plugs (8-mm diameter), obtained from the actively growing colony and incubated at 25°C for 7 days. DMSO was used as the negative control whereas fluconazole was used as the positive control. The experiments were performed in triplicates. Diameter of the fungal colonies was measured and expressed as percent mycelial inhibition determined by applying the formula [55].

Inhibition of mycelial growth  % = ( d c - d t ) ∕ d c × 100

where dc average diameter of fungal colony in negative control plates, dt average diameter of fungal colony in experimental plates.

Abbreviations

DMSO:

dimethylsulfoxide

MIC:

minimum inhibitory concentration

MTCC:

microbial-type culture collection

SDA:

Sabouraud dextrose agar

TZDs:

thiazolidine-2,4-dione.

References

  1. Berber I, Cokmus C, Atalan E: Characterization of Staphylococcus species by SDS-PAGE of whole cell and extracellular proteins. Microbiology 2003, 72: 42–47. 10.1023/A:1022221905449

    Article  CAS  Google Scholar 

  2. Bildirici I, Sener A, Tozlu I: Further derivatives of 4-benzoyl-1, 5-diphenyl-1H pyrazole-3-carboxylic acid and their antibacterial activities. Med Chem Rev 2007, 16: 418–426. 10.1007/s00044-007-9082-z

    CAS  Google Scholar 

  3. Sung WS, Jung HJ, Park K, Kim HS, Lee Ln-S, Lee DG: 2, 5-Dimethyl-4-hydroxy-3(2H)-furanone (DMHF): antimicrobial compound with cell cycle arrest in nosocomial pathogens. Life Sci 2007, 80: 586–591. 10.1016/j.lfs.2006.10.008

    Article  CAS  Google Scholar 

  4. Aggarwal R, Kumar V, Tyagi P, Singh SP: Synthesis and antibacterial activity of some new 1-heteroaryl-5-amino-3H/methyl-4-phenylpyrazoles. Bioorg Med Chem 2006, 14: 1785–1791. 10.1016/j.bmc.2005.10.026

    Article  CAS  Google Scholar 

  5. Kumar V, Aggarwal R, Tyagi P, Singh SP: Synthesis and antibacterial activity of some new 1-heteroaryl-5-amino-4-phenyl-3-trifluoromethylpyrazoles. Eur J Med Chem 2005, 40: 922–927. 10.1016/j.ejmech.2005.03.021

    Article  CAS  Google Scholar 

  6. Kane JL, Hirth BH, Liang B, Gourlie BB, Nahill S, Barsomian G: Ureas of 5-aminopyrazole and 2-aminothiazole inhibit growth of gram-positive bacteria. Bioorg Med Chem Lett 2003, 13: 4463–4466. 10.1016/j.bmcl.2003.09.013

    Article  CAS  Google Scholar 

  7. Deohate PP, Deohate JP, Berad BN: Synthesis of some novel 1, 2, 4-dithiazolidines and their antibacterial and antifungal activity. Asian J Chem 2004, 16: 255–260.

    CAS  Google Scholar 

  8. Prakash O, Kumar R, Parkash V: Synthesis and antifungal activity of some new 3-hydroxy-2-(1-phenyl-3-aryl-4-pyrazolyl)chromones. Eur J Med Chem 2008, 43: 435–440. 10.1016/j.ejmech.2007.04.004

    Article  CAS  Google Scholar 

  9. Mares D, Romagnoli C, Andreotti E, Manfrini M, Vicentini CB: Synthesis and antifungal action of new tricyclazole analogues. J Agric Food Chem 2004, 52: 2003–2009. 10.1021/jf030695y

    Article  CAS  Google Scholar 

  10. Prakash O, Aneja DK, Arora S, Sharma C, Aneja KR: Synthesis and antimicrobial activities of some new 5-((3-(aryl)-1-phenyl-1H-pyrazol-4-yl)methylene)-3-phenylthiazolidine-2, 4-diones. Med Chem Res 2010.

    Google Scholar 

  11. Romagnoli C, Mares D, Bruni A, Andreotti E, Manfrini M, Vicentini CB: Antifungal activity of 5 new synthetic compounds vs. Trichophyton rubrum and Epidermophyton floccosum. Mycopathologia 2001, 153: 129–132.

    Article  Google Scholar 

  12. Chen H, Li Z, Han Y: Synthesis and fungicidal activity against Rhizoctonia solani of 2-alkyl (alkylthio)-5-pyrazolyl-1, 3, 4-oxadiazoles (thiadiazoles). J Agric Food Chem 2000, 48: 5312–5315. 10.1021/jf991065s

    Article  CAS  Google Scholar 

  13. Singh N, Sangwan NK, Dhindsa KS: Synthesis and fungitoxic activity of 5-aryl-1-formyl-4, 5-dihydro-3-(2-hydroxyphenyl)-1H-pyrazoles and their complexes. Pest Manag Sci 2000, 56: 284–288. 10.1002/(SICI)1526-4998(200003)56:3<284::AID-PS128>3.0.CO;2-M

    Article  CAS  Google Scholar 

  14. Tanitame A, Oyamada Y, Ofuji K, Fujimoto M, Suzuki K, Ueda T, Tearuchi H, Kawasaki M, Nagai K, Wachi M, Yamagishi J: Synthesis and antibacterial activity of novel and potent DNA gyrase inhibitors with azole ring. Bioorg Med Chem 2004, 12: 5515–5524. 10.1016/j.bmc.2004.08.010

    Article  CAS  Google Scholar 

  15. Kees KL, Fitzgerald JJ, Steiner KE, Mattes JF, Mihan B, Tosi T, Moondoro D, McCaleb ML: New potent antihyperglycemic in db/db mice: synthesis and structure-activity relationship studies of (4-substituted benzyl)(trifloromethyl)pyrazoles and -pyrazolones. J Med Chem 1996, 39: 3920–3928. 10.1021/jm960444z

    Article  CAS  Google Scholar 

  16. Meazza G, Bettarini F, Porta PL, Piccardi P, Signorini E, Portoso D, Fornara L: Synthesis and herbicidal activity of novel heterocyclic protoporphyrinogen oxidase inhibitors. Pest Manag Sci 2004, 60: 1178–1188. 10.1002/ps.923

    Article  CAS  Google Scholar 

  17. Waldrep TW, Beck JR, Lynch MP, Wright FL: Synthesis and herbicidal activity of 1-aryl-5-halo- and 1-aryl-5-(trifluoromethyl)-1H-pyrazole-4-carboxamides. J Agric Food Chem 1990, 38: 541–544. 10.1021/jf00092a045

    Article  CAS  Google Scholar 

  18. Park H-J, Lee K, Park S-J, Ahn B, Lee J-C, Cho HY, Lee K-I: Identification of antitumor activity of pyrazole oxime ethers. Bioorg Med Chem Lett 2005, 15: 3307–3312. 10.1016/j.bmcl.2005.03.082

    Article  CAS  Google Scholar 

  19. Hatheway GJ, Hansch C, Kim KH, Milstein SR, Schmidt CL, Smith RN: Antitumor 1-(X-aryl)-3, 3-dialkyltriazenes. 1. Quantitative structure-activity relationships vs. L1210 Leukemia in Mice. J Med Chem 1978, 21: 563–574. 10.1021/jm00204a012

    Article  CAS  Google Scholar 

  20. Katayama H, Oshiyama T: Preparation and bioactivity of pyrazole derivatives as potential cross-linking agent. Can J Chem 1997, 75: 913–919.

    Article  CAS  Google Scholar 

  21. Manfredini S, Bazzanini R, Baraaldi PG, Guameri M, Simoni D, Marongiu ME, Pani A, Tramontano E, Colla PL: Pyrazole-related nucleosides. Synthesis and antiviral/antitumor activity of some substituted pyrazole and pyrazolo[4,3-d]-1,2,3-triazin-4-one nucleosides. J Med Chem 1992, 35: 917–924. 10.1021/jm00083a017

    Article  CAS  Google Scholar 

  22. Wustrow DJ, Rubin CR, Knobelsdorf JA, Akunne H, MacKenzie DR, Pugsley TA, Zoski KT, Heffner TG, Wise LD: Pyrazolo[1, 5-a]pyrimidine CRF-1 receptor antagonists. Bioorg Med Chem Lett 1998, 8: 2067–2070. 10.1016/S0960-894X(98)00372-2

    Article  CAS  Google Scholar 

  23. Habeeb AG, Rao PNP, Knaus EE: Design and synthesis of celecoxib and rofecoxib analogues as selective cyclooxygenase-2 (COX-2) inhibitors: replacement of sulfonamide and methylsulfonyl pharmacophores by an azido bioisostere. J Med Chem 2001, 44: 3039–3042. 10.1021/jm010153c

    Article  CAS  Google Scholar 

  24. Martel AM, Graul A, Rabbaseda X, Castaner R: Slidenafil: treatment of erectile dysfunction, phosphodiesterase V inhibitor. Drugs Future 1997, 22: 138–143.

    Article  CAS  Google Scholar 

  25. Yoshioka T, Fujita T, Kanai T, Aizava Y, Kurumada T, Hasegava K, Horikoshi H: Studies on hindered phenols and analogues. 1. Hypolipidemic and hypoglycaemic agents with ability to inhibit lipid peroxidation. J Med Chem 1989, 32: 421–428. 10.1021/jm00122a022

    Article  CAS  Google Scholar 

  26. Lee HW, Kim BY, Ahn JB, Kang SW, Lee JH, Shin JS, Ahn SK, Lee SJ, Yoon SS: Molecular design, synthesis, and hypoglycaemic and hypolipidemic activities of novel pyrimidine derivatives having thiazolidinedione. Eur J Med Chem 2005, 40: 862–874. 10.1016/j.ejmech.2005.03.019

    Article  CAS  Google Scholar 

  27. Bozdag-Dundar O, Verspohl EJ, Das-Evcimen N, Kaup RM, Bauer K, Sarikaya M, Evranos B, Ertan R: Synthesis and biological activity of some new flavonyl-2, 4-thiazolidinediones. Bioorg Med Chem 2008, 16: 6747–6751. 10.1016/j.bmc.2008.05.059

    Article  Google Scholar 

  28. Eun JS, Kim KS, Kim HN, Park SA, Ma T, Lee KA, Kim DK, Kim HK, Kim IS, Jung YH, Zee OP, Yoo DJ, Kwak YG: Synthesis of psoralen derivatives and their blocking effect of hkv1.5 channel. Arch Pharm Res 2007, 30: 155–160. 10.1007/BF02977688

    Article  CAS  Google Scholar 

  29. Mori M, Takagi M, Noritake C, Kagabu S: 2, 4-Dioxo-1, 3-thiazolidine derivatives as a lead for new fungicides. J Pestic Sci 2008, 33: 357–363. 10.1584/jpestics.G08-15

    Article  CAS  Google Scholar 

  30. Sahu SK, Banerjee M, Mishra SK, Mohanta RK: Synthesis, partition coefficient and antibacterial activity of 3'-phenyl(substituted)-6'-aryl-2'(1H)-cis-3', 3'a-dihydrospiro[3-H-indole-3, 5'-pyrazolo (3', 4'-d)-thiazolo-2-(1H)-ones]. Acta Pol Pharm Drug Res 2007, 64: 121–126.

    CAS  Google Scholar 

  31. Dwivedi C, Gupta TK, Parmar SS: Substituted thiazolidones as anticonvulsants. J Med Chem 1972, 15: 553–554. 10.1021/jm00275a031

    Article  CAS  Google Scholar 

  32. Verma A, Saraf SK: 4-Thiazolidinone--a biological active scaffold. Eur J Med Chem 2008, 43: 897–905. 10.1016/j.ejmech.2007.07.017

    Article  CAS  Google Scholar 

  33. Ceriello A: Thiazolidinediones as anti-inflammatory and anti-atherogenics. Diab Met Res Rev 2008, 24: 14–26. 10.1002/dmrr.790

    Article  CAS  Google Scholar 

  34. Bozdag-Dundar O, Ozgen O, Mentese A, Altanlar N, Atli O, Kendib E, Eetana R: Synthesis and antimicrobial activity of some new thiazolyl thiazolidine-2, 4-dione derivatives. Bioorg Med Chem 2007, 15: 6012–6017. 10.1016/j.bmc.2007.06.049

    Article  Google Scholar 

  35. Brooke EW, Davies SG, Mulvaney AW, Okada M, Pompeo F, Sim E, Vickers RJ, Westwood IM: Synthesis and in vitro evaluation of novel small molecule inhibitors of bacterial arylamine N-acetyltransferases (NATs). Bioorg Med Chem Lett 2003, 13: 2527–2530. 10.1016/S0960-894X(03)00484-0

    Article  CAS  Google Scholar 

  36. Tuncbilek M, Altanlar N: Synthesis and antimicrobal evaluation of some 3-(substituted phenacyl)-5-[4'-(4H-oxo-1-benzopyran-2-yl)-benzylidene]-2, 4-thiazolidinediones. IL Farmaco 1999, 54: 475–478. 10.1016/S0014-827X(99)00054-3

    Article  CAS  Google Scholar 

  37. Tuncbilek M, Bozda O, Bozdag-Dundar O, Ayhan-Kilcigil G, Ceylan M, Waheed A, Verspohl EJ, Ertan R: Synthesis and hypoglycemic activity of some substituted flavonyl thiazolidinedione derivatives-fifth communication: flavonyl benzyl substituted 2, 4-thiazolidinediones. IL Farmaco 2003, 58: 79–83. 10.1016/S0014-827X(02)01241-7

    Article  CAS  Google Scholar 

  38. Pomel V, Klicic J, Covini D, Church DD, Shaw JP, Roulin K, Burgat-Charvillon F, Valognes D, Camps M, Chabert C, Gillieeron C, Francon B, Perrin D, Leroy D, Gretener D, Nichols A, Vitte PA, Carboni S, Rommel C, Schwarz MK, Ruckle T: Furan-2-ylmethylene thiazolidinediones as novel, potent, and selective inhibitors of phosphoinositide-3-kinase γ. J Med Chem 2006, 49: 3857–3871. 10.1021/jm0601598

    Article  CAS  Google Scholar 

  39. Bozdag-Dundar O, Evranos B, Das-Evcimen N, Sarikaya M, Ertan R: Synthesis and aldose reductase inhibitory activity of some new chromonyl-2, 4-thiazolidinediones. Eur J Med Chem 2008, 43: 2412–2417. 10.1016/j.ejmech.2008.01.004

    Article  CAS  Google Scholar 

  40. Youssef AM, White MS, Villanueva EB, El-Ashmawy IM, Klegeris A: Synthesis and biological evaluation of novel pyrazolyl-2, 4-thiazolidinediones as anti-inflammatory and neuroprotective agents. Bioorg Med Chem 2010, 18: 2019–2028. 10.1016/j.bmc.2010.01.021

    Article  CAS  Google Scholar 

  41. Prakash O, Kumar M, Kumar R, Sharma C, Aneja KR: Hypervalent Iodine(III) mediated synthesis of novel unsymmetrical 2, 5-disubstituted 1, 3, 4-oxadiazoles as antibacterial and antifungal agents. Eur J Med Chem 2010, 45: 4252–4257. 10.1016/j.ejmech.2010.06.023

    Article  CAS  Google Scholar 

  42. Prakash O, Kumar R, Sehrawat R: Synthesis and antibacterial activity of some new 2, 3-dimethoxy-3-hydroxy-2-(1-phenyl-3-aryl-4-pyrazolyl)chromanones. Eur J Med Chem 2009, 44: 1763–1767. 10.1016/j.ejmech.2008.03.028

    Article  CAS  Google Scholar 

  43. Kumar R, Nair RR, Dhiman SS, Sharma J, Prakash O: Organoiodine(III)-mediated synthesis of 3-aryl/heteroaryl-5, 7-dimethyl-1, 2, 4-triazolo[4, 3-c]pyrimidines as antibacterial agents. Eur J Med Chem 2009, 44: 2260–2264. 10.1016/j.ejmech.2008.06.004

    Article  CAS  Google Scholar 

  44. Prakash O, Aneja DK, Wadhwa D, Kumar R: A facile synthesis of novel dihydroindeno[1, 2-e][1, 2, 4]triazolo[3, 4-b][1, 3, 4]thiadiazines using HTIB. J Heterocycl Chem 2011. doi:10.1002/jhet.815

    Google Scholar 

  45. Kira MA, Abdel-Rahman MO, Gadalla KZ: The Vilsmeier-Haack reaction-III cyclization of hydrazones to pyrazoles. Tetrahedron Lett 1969, 10: 109–110. 10.1016/S0040-4039(01)88217-4

    Article  Google Scholar 

  46. Bernard M, Hulley E, Molenda H, Stochla K, Wrzeciono U: Azoles. 17. Beta-(4-pyrazol)acrylic and propionic acids and their anti-inflammatory activity. Pharmazie 1986, 41: 560–562.

    CAS  Google Scholar 

  47. De Luca L, Giacomelli G, Masala S, Porchddu A: A mild procedure for the preparation of 3-aryl-4-formylpyrazoles. Synlett 2004, 13: 2299–2302.

    Google Scholar 

  48. Xie Y, Liu Y, Gong G, Rinderspacher A, Deng S-X, Smith DH, Toebben U, Tzilianos E, Branden L, Vidovic D, Chung C, Schurer S, Tautz L, Landry DW: Discovery of a novel submicromolar inhibitor of the lymphoid specific tyrosine phosphatase. Bioorg Med Chem Lett 2008, 18: 2840–2844. 10.1016/j.bmcl.2008.03.079

    Article  CAS  Google Scholar 

  49. Pattana SR, Kekareb P, Patlic A, Nikaljec A, Kitturd BS: Studies on the synthesis of novel 2, 4-thiazolidinedione derivatives with antidiabetic activity. Iran J Pharm Sci 2009, 5: 225–230.

    Google Scholar 

  50. El-Deeb IM, Bayoumi SM, El-Sherbeny MA, Abdel-Aziz AA-M: Synthesis and antitumor evaluation of novel cyclic arylsulfonylureas: ADME-T and pharmacophore prediction. Eur J Med Chem 2010, 45: 2516–2530. 10.1016/j.ejmech.2010.02.038

    Article  CAS  Google Scholar 

  51. Kumar BRP, Soni M, Kumar SS, Singh K, Patil M, Baig RBN, Adhikari L: Synthesis, glucose uptake activity and structure-activity relationships of some novel glitazones incorporated with glycine, aromatic and alicyclic amine moieties via two carbon acyl linker. Eur J Med Chem 2011, 46: 835–844. 10.1016/j.ejmech.2010.12.019

    Article  CAS  Google Scholar 

  52. Aneja KR, Sharma C, Joshi R: Fungal infection of the ear: a common problem in the north eastern part of Haryana. Int J Pediatr Otorhinolaryngol 2010, 74: 604–607. 10.1016/j.ijporl.2010.03.001

    Article  CAS  Google Scholar 

  53. Ahmad I, Beg AZ: Antimicrobial and phytochemical studies on 45 Indian medicinal plants against multi-drug resistant human pathogens. J Ethnopharmacol 2001, 74: 113–123. 10.1016/S0378-8741(00)00335-4

    Article  CAS  Google Scholar 

  54. Villanova PA: NCCLS, National Committee for Clinical Laboratory Standards. 2000.

    Google Scholar 

  55. Al-Burtamami SKS, Fatope MO, Marwah RG, Onifade AK, Al-Saidi SH: Chemical composition, antibacterial and antifungal activities of the essential oil of halophyllum tuberculatum from Oman. J Ethnopharmacol 2005, 96: 107–112. 10.1016/j.jep.2004.08.039

    Article  Google Scholar 

Download references

Acknowledgements

DKA and PL are thankful to the CSIR and UGC, New Delhi, for providing JRF and SRF, respectively. We are grateful to the Director, SAIF, Punjab University, Chandigarh, for carrying out mass spectrometric analysis. Thanks are due to the CDRI, Lucknow, for carrying out elemental analysis.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Deepak K Aneja.

Additional information

Competing interests

The authors declare that they have no competing interests.

and Om Prakash contributed equally to this work.

Electronic supplementary material

13588_2011_16_MOESM1_ESM.JPEG

Additional file 1: 1 H NMR Spectra .(4a); 1H NMR of ethyl 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (JPEG 733 KB)

13588_2011_16_MOESM2_ESM.JPEG

Additional file 2: 1 H NMR Spectra .(4b); 1H NMR of ethyl 2-((Z)-2, 4-dioxo-5-((1-phenyl-3-p-tolyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (JPEG 693 KB)

13588_2011_16_MOESM3_ESM.JPEG

Additional file 3: 1 H NMR Spectra .(4c); 1H NMR of ethyl 2-((Z)-5-((3-(4-methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 539 KB)

13588_2011_16_MOESM4_ESM.JPEG

Additional file 4: 1 H NMR Spectra .(4d); 1H NMR of ethyl 2-((Z)-5-((3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 579 KB)

13588_2011_16_MOESM5_ESM.JPEG

Additional file 5: 1 H NMR Spectra .(4e); 1H NMR of ethyl 2-((Z)-5-((3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 552 KB)

13588_2011_16_MOESM6_ESM.JPEG

Additional file 6: 1 H NMR Spectra .(4f); 1H NMR of ethyl 2-((Z)-5-((3-(4-bromophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 590 KB)

13588_2011_16_MOESM7_ESM.JPEG

Additional file 7: 1 H NMR Spectra .(4g); 1H NMR of ethyl 2-((Z)-5-((3-(4-hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 636 KB)

13588_2011_16_MOESM8_ESM.JPEG

Additional file 8: 1 H NMR Spectra .(4h); 1H NMR of ethyl 2-((Z)-5-((3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 580 KB)

13588_2011_16_MOESM9_ESM.JPEG

Additional file 9: 1 H NMR Spectra .(5a); 1H NMR of methyl 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (JPEG 560 KB)

13588_2011_16_MOESM10_ESM.JPEG

Additional file 10: 1 H NMR Spectra .(5b); 1H NMR of methyl 2-((Z)-2, 4-dioxo-5-((1-phenyl-3-p-tolyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetate (JPEG 572 KB)

13588_2011_16_MOESM11_ESM.JPEG

Additional file 11: 1 H NMR Spectra .(5c); 1H NMR of methyl 2-((Z)-5-((3-(4-methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 553 KB)

13588_2011_16_MOESM12_ESM.JPEG

Additional file 12: 1 H NMR Spectra .(5d); 1H NMR of methyl 2-((Z)-5-((3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 533 KB)

13588_2011_16_MOESM13_ESM.JPEG

Additional file 13: 1 H NMR Spectra .(5e); 1H NMR of methyl 2-((Z)-5-((3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 555 KB)

13588_2011_16_MOESM14_ESM.JPEG

Additional file 14: 1 H NMR Spectra .(5f); 1H NMR of methyl 2-((Z)-5-((3-(4-bromophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 696 KB)

13588_2011_16_MOESM15_ESM.JPEG

Additional file 15: 1 H NMR Spectra .(5g); 1H NMR of methyl 2-((Z)-5-((3-(4-hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 631 KB)

13588_2011_16_MOESM16_ESM.JPEG

Additional file 16: 1 H NMR Spectra .(5h); 1H NMR of methyl 2-((Z)-5-((3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetate (JPEG 718 KB)

13588_2011_16_MOESM17_ESM.JPEG

Additional file 17: 1 H NMR Spectra .(6a); 1H NMR of 2-((Z)-2, 4-dioxo-5-((1, 3-diphenyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetic acid (JPEG 743 KB)

13588_2011_16_MOESM18_ESM.JPEG

Additional file 18: 1 H NMR Spectra .(6b); 1H NMR of 2-((Z)-2, 4-dioxo-5-((1-phenyl-3-p-tolyl-1H-pyrazol-4-yl)methylene)thiazolidin-3-yl)acetic acid (JPEG 754 KB)

13588_2011_16_MOESM19_ESM.JPEG

Additional file 19: 1 H NMR Spectra .(6c); 1H NMR of 2-((Z)-5-((3-(4-methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (JPEG 704 KB)

13588_2011_16_MOESM20_ESM.JPEG

Additional file 20: 1 H NMR Spectra .(6d); 1H NMR of 2-((Z)-5-((3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (JPEG 769 KB)

13588_2011_16_MOESM21_ESM.JPEG

Additional file 21: 1 H NMR Spectra .(6e); 1H NMR of 2-((Z)-5-((3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (JPEG 837 KB)

13588_2011_16_MOESM22_ESM.JPEG

Additional file 22: 1 H NMR Spectra .(6f); 1H NMR of 2-((Z)-5-((3-(4-bromophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (JPEG 763 KB)

13588_2011_16_MOESM23_ESM.JPEG

Additional file 23: 1 H NMR Spectra .(6g); 1H NMR of 2-((Z)-5-((3-(4-hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (JPEG 669 KB)

13588_2011_16_MOESM24_ESM.JPEG

Additional file 24: 1 H NMR Spectra .(6h); 1H NMR of 2-((Z)-5-((3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2, 4-dioxothiazolidin-3-yl)acetic acid (JPEG 629 KB)

Rights and permissions

Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (https://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Aneja, D.K., Lohan, P., Arora, S. et al. Synthesis of new pyrazolyl-2, 4-thiazolidinediones as antibacterial and antifungal agents. Org Med Chem Lett 1, 15 (2011). https://doi.org/10.1186/2191-2858-1-15

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/2191-2858-1-15

Keywords