A Convenient, Rapid Microwave Assisted Synthesis of Some Novel Imidazole Derivatives and Their Antimicrobial Activity

 

Dr. Dimple K. Rathore*, Dr. Vinod K. Sharma

Microwave Chemistry Laboratory, M. L. Sukhadia University, Udaipur, Rajasthan, India.

*Corresponding Author E-mail: dimple01rathore@gmail.com

 

ABSTRACT:

A series of imidazole derivatives were synthesized by condensation of, differently substituted 4-benzylidene-2-phenyloxazol-5(4H)-one and ammonia, which on further reaction with barbituric acid produces the final products (substituted 5-((5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-triones) 3(a-f). The structures of the newly synthesized compounds were supported by IR, 1H NMR, 13C NMR and MASS spectral data. All the reactions were carried out by environmental benign, efficient and extremely fast procedure microwave assisted synthesis. The derivatives of these moieties were screened for antibacterial and antifungal activity. It was seen that the compounds showed more antibacterial activity towards the test organisms S. pyogenus and S. aureus and significant activity against all strains of fungi.

 

KEYWORDS: Microwave assisted synthesis, Imidazole, Antibacterial activity, Antifungal activity.

 

 

 

INTRODUCTION:

In the context of green chemistry, among the nonconventional methods of reaction activation in organic synthesis, microwave irradiation for reaction activation provides an alternative to the conventional heating for introducing energy into chemical reactions by using the ability of some liquids and solids to transform electromagnetic energy into heat. This in situ mode of heat generation has attracted many chemists because its magnitude depends on the dielectric properties of the molecules. The microwave-assisted reactions are fast, clean, economic and eco-friendly and this technique has been proposed as the “technology of tomorrow”.

 

During recent years, microwaves have been extensively used for carrying out chemical reactions and have become a useful non-conventional energy source for performing organic synthesis1.

 

Imidazole a five membered heterocycle having 3 carbon atom, 2 nitrogen atom and two double bond – appears in a no. of naturally accuring products like the amino acids, histidine and purines which comprises many of the most important bases in nucleic acids. Imidazole derivatives possess a broad spectrum of pharmacological activities2-5such as  anti-parkinson, anticonvulsant and monoamineoxidase (MAO) inhibitory activity6-8, antirheumatoid arthritis 9, antiepileptic 10, anti-imflammatory11-12, antibacterial activity 13-14, antifungal activity 15 antitubercular 16, antiviral 17 and anticancer activity18-20 (i.e. possess significant cytotoxic activity against Dalton’s Lymphoma Ascites (DLA) and Ehrlich’s Ascites Carcinoma (EAC) cell lines.).

 

Barbiturates are drugs that act as central nervous system depressants, and, by virtue of this, they produce a wide spectrum of effects, from mild sedation to total anesthesia.

In the view of above mentioned biological activity of imidazole derivatives and in continuation of our interest in the development of environmentally benign protocols, we here in report a facile and rapid synthesis of 5-((5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-triones derivatives under microwave irradiation. We have developed an efficient method for incorporation of imidazole derivatives and barbiturates in one frame work and hope to obtain a few compounds having good antibacterial and antifungal activity. The synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR and MASS spectral data.

 

EXPERIMENTAL SECTION:

Chemicals were purchased from commercial supplier and were used without any further purification. All the reactions were carried out in a Modified Microwave oven (Kenstar, model no: OM26.EGO). Melting point was determined by open capillary method and is uncorrected. The purity of the compound was ascertained by percolated TLC using silica gel G using ethyl acetate: n-hexane (7:3) as an eluent. The spots were visualized by using iodine vapors. The IR spectra were recorded on FT IR Spectrometer Shimadzu 8201. The 1H NMR spectra were obtained using a Bruker Advance spectrospin 400 (400 MHz) instrument using TMS as internal standard. 13C NMR on a Varian AMX 400 (100 MHz) spectrometer as solutions in CDCl3. Mass spectra were recorded on Accu TOF MS ES+.

 

1(a-f) - General procedure for Synthesis of substituted 4-methylene-2-phenyloxazol-5(4H)-one

Hippuric acid (0.01 mole), Sodium acetate (0.01 mole) and aldehyde (0.01 mole) are finely powdered and mixed in beaker. To the above mixture add acetic anhydride (5ml for 1 gm).The reaction mixture was irradiated under microwave for 3 to 4 min. at 480W with intermitted irradiation of 30 sec. interval. Upon completion of reaction (monitored by TLC), alcohol was added to the reaction mixture for purification and kept overnight, which was then filtered.  The filtered product was washed several times with water and dried. Above reaction was carried based on the methods described in the literature21.

 

2(a-f) Synthesis of 4-substituted methylene-2-phenyl-1H-imidazol-5(4H)-one

The compound 1 (0.01 mole) is taken in Erlenmeyer flask in which alcohol (approx.) is added as solvent. To the above mixture ammonia (0.01 mole) was added. The above reaction mixture was irradiated under microwave irradiation for 5 min. at 360–480 W with intermitted irradiation of 30 followed by 15 sec. The progress of the reaction was monitored by TLC. After the reaction was completed the product was filtered, concentrated and left for crystallization. The product was purified and recrystallized with alcohol.

 

2a- 4-benzylidene-2-phenyl-1H-imidazol-5(4H)-one

Molecular Formula C16H12N2O; Yield (%) 92; mp 135°C; IR (KBr): nmax -3301 (NH amide),3197 [amine (sec.)], 1660 (C=O), 1617 (C=N) 1592 (C=C); 1H NMR (300 MHz, DMSO-d6: 7.07-7.73 (m, 10H, Ar-H), 3.92 (s, 1H, C=CH), 3.05 (s, 1H, NH);  13C NMR (CDCl3) (δ/ppm); 114.6, 130.3 (C=C), 157.9 (C=N), 167.4 (-NH-CO-), 128.2, 128.8, 130.1, 131.8 (Ar-C), 127.9, 128.5, 128.6, 135.2 (Ar-C). Anal. Calc. C, 77.40; H, 4.87; N, 11.28; O, 6.44. Found: C, 77.37; H, 4.81; N, 11.23; O, 6.40.

 

2b- 4-(4-fluorobenzylidene)-2-phenyl-1H-imidazol-5(4H)-one

Molecular Formula C16H11FN2O; Yield (%) 87; mp 150°C; IR (KBr): nmax -3298 (NH amide), 3194 [amine (sec.)], 1657 (C=O), 1614 (C=N), 1589 (C=C), 762 (C-F); 1H NMR (300 MHz, DMSO-d6: 6.73-7.39(m, 9H, Ar-H), 3.58 (s, 1H, C=CH), 2.71 (s, 1H, NH);  13C NMR (CDCl3) (δ/ppm); 114.6, 130.3 (C=C), 157.9 (C=N), 167.4 (-NH-CO-), 128.2, 128.8, 130.1, 131.8 (Ar-C), 115.4, 130.4, 130.8, 162.1 (Ar-C). Anal. Calc. C, 72.17; H, 4.16; F, 7.14; N, 10.52; O, 6.01. Found: C, 72.11; H, 4.10; F, 7.10; N, 10.49; O, 5.97.

 

2c- 4-(4-chlorobenzylidene)-2-phenyl-1H-imidazol-5(4H)-one

Molecular Formula C16H11ClN2O; Yield (%) 88; mp 95°C; IR (KBr): nmax -3292 (NH amide), 3188 [amine (sec.)], 1651 (C=O), 1608 (C=N), 1583 (C=C), 1139 (C-Cl); 1H NMR (300 MHz, DMSO-d6: 6.95-7.61 (m, 9H, Ar-H), 3.8 (s, 1H, C=CH), 2.93 (s, 1H, NH);  13C NMR (CDCl3) (δ/ppm); 114.6, 130.3 (C=C), 157.9 (C=N), 167.4 (-NH-CO-), 128.2, 128.8, 130.1, 131.8 (Ar-C), 128.7, 129.0, 133.3, 133.5 (Ar-C). Anal. Calc. C, 67.97; H, 3.92; Cl, 12.54; N, 9.91; O, 5.66. Found: C, 67.90; H, 3.89; Cl, 12.50; N, 9.87; O, 5.61.

 

2d- 4-(4-hydroxybenzylidene)-2-phenyl-1H-imidazol-5(4H)-one

Molecular Formula C16H11N3O3; Yield (%) 90; mp 128°C; IR (KBr): nmax -3289 (NH amide), 3184 [amine (sec.)], 1647 (C=O), 1604 (C=N), 1579 (C=C), 3511 (O-H); 1H NMR (300 MHz, DMSO-d6: 6.76-7.42(m, 9H, Ar-H), 3.61 (s, 1H, C=CH), 2.74 (s, 1H, NH), 9.78 (S, 1H, OH);  13C NMR (CDCl3) (δ/ppm); 114.6, 130.3 (C=C), 157.9 (C=N), 167.4 (-NH-CO-), 128.2, 128.8, 130.1, 131.8 (Ar-C), 115.8, 127.8, 130.6, 157.7 (Ar-C). Anal. Calc. C, 72.72; H, 4.58; N, 10.60; O, 12.11. Found: C, 72.67; H, 4.53; N, 10.55; O, 12.07.

 

 

2e- 4-(3-nitrobenzylidene)-2-phenyl-1H-imidazol-5(4H)-one

Molecular Formula C16H12N2O2; Yield (%) 89; mp 118°C; IR (KBr): nmax -3286 (NH amide), 3182 [amine (sec.)], 1645 (C=O), 1602 (C=N), 1577 (C=C), 1527 , 1352 (NO2); 1H NMR (300 MHz, DMSO-d6: 7.35s (s, 1H, Ar-H), 7.45-8.11 (m, 8H, Ar-H), 4.3 (s, 1H, C=CH), 3.43 (s, 1H, NH);  13C NMR (CDCl3) (δ/ppm); 114.6, 130.3 (C=C), 157.9 (C=N), 167.4 (-NH-CO-), 128.2, 128.8, 130.1, 131.8 (Ar-C), 122.7, 123.1, 129.5, 134.6, 136.16, 147.8 (Ar-C). Anal. Calc. C, 65.53; H, 3.78; N, 14.33; O, 16.37. Found: C, 65.50; H, 3.73; N, 14.30; O, 16.31.`MS: (m/z) 106.0 [C6H4NO]+, 122.0 [C6H4NO2]+, 145.0[C8H5N2O]+, 171.1 [C10H7N2O]+, 196.1 [C12H8N2O]+, 200.0 [C10H6N3O2]+ , 216.0 [C10H6N3O3]+, 222.1 [C14H10N2O]+, 225.1 [C12H7N3O2]+, 251.1 [C14H9N3O2]+, 267.1 [C14H9N3O3]+, 277.1 [C10H11N3O2]+, 293.1 [C16H11N3O3]+.

 

2f- 4-(furan-2-ylmethylene)-2-phenyl-1H-imidazol-5(4H)-one

Molecular Formula C14H10N2O2; Yield (%) 91; mp 144°C; IR (KBr): nmax -3281 (NH amide), 3177 [amine (sec.)], 1642 (C=O), 1601 (C=N), 1575 (C=C), 1094 (C-O-C), 734 (furan); 1H NMR (300 MHz, DMSO-d6: 7.35s (s, 1H, Ar-H), 7.45-8.11 (m, 8H, Ar-H), 4.3 (s, 1H, C=CH), 3.43 (s, 1H, NH);  13C NMR (CDCl3) (δ/ppm); 132.3, 136.3 (C=C), 157.9 (C=N), 167.4 (-NH-CO-), 128.2, 128.8, 130.1, 131.8 (Ar-C), 109.5, 112.7, 143.7, 151.5 (furan). Anal. Calc. C, 70.58; H, 4.23; N, 11.76; O, 13.43. Found: C, 70.52; H, 4.20; N, 11.71; O, 13.39.

 

3(a-f) Synthesis of 5-((5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-triones

The compound 2(a-f) (0.01 mole) is taken in Erlenmeyer flask and dissolved in DMF. To the above solution Barbituric acid (0.01) is added and 7 to 8 drops of pyridine was added as catalyst. The above reaction mixture was irradiated under microwave irradiation for 6 min. at 480W with intermitted irradiation of 30 followed by 15 sec. The progress of the reaction was monitored by TLC. After the reaction was completed the product was filtered, concentrated and left for crystallization. The products were purified and recrystallized with mixture of alcohol and acetone (1:1).

 

3a- 5-((5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)(phenyl)methyl)pyrimidine-2,4,6(1H,3H,5H)-trione

Molecular Formula C20H16N4O4; Yield (%) 89; mp 165°C; IR (KBr): nmax - 3192 (NH amide), 3080(N (sec) 2858 (ArH), 1678,1699 (C=O), 1585 (C=N), 2818 (tert. alkane); 1H NMR (300 MHz, DMSO-d6: 2.01- 3.26 (m,d,d, 3H, tert.H), 10.6 (s, 1H, NH), 11.08 (s, 2H, NH), 6.52-8.06 (m, 10H,  Ar);  13C NMR (CDCl3) (δ/ppm); 164.4 (C=N), 177.4 (NH-CO-), 70.0, 30.7 (C-C), 23.3, 150.4, 169.3 (barbiturate),  128.8, 131.3, 131.0, 133.0 (Ar-C), 126.1, 125.9, 128.4, 148.4 (Ar-C). Anal. Calc. C, 63.82; H, 4.28; N, 14.89; O, 17.00. Found: C, 63.79; H, 4.23; N, 14.83; O, 16.97.

 

3b- 5-((4-fluorophenyl)(5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-trione

Molecular Formula C20H15FN4O4; Yield (%) 86; mp  143°C; IR (KBr): nmax - 3195 (NH amide), 3083 (N (sec)), 2862 (ArH), 1682,1700 (C=O), 1588 (C=N), 762 (C-F), 2822 (tert. alkane); 1H NMR (300 MHz, DMSO-d6 : 1.86-2.97 (m,d,d, 3H, tert.H), 10.1 (s, 1H, NH), 10.91 (s, 2H, NH), 6.18-7.72  (m, 9H,  Ar); 13C NMR (CDCl3) (δ/ppm); 164.4 (C=N), 177.4 (NH-CO-), 70.0, 30.7 (C-C), 23.3, 150.4, 169.3 (barbiturate),  128.8, 131.3, 131.0, 133.0 (Ar-C), 115.2, 129.3, 144.0, 160.1 (Ar-C). Anal. Calc. C, 60.91; H, 3.83; F, 4.82; N, 14.21; O, 16.23. Found: C, 60.87; H, 3.80; F, 4.77; N, 14.19; O, 16.20.

 

3c– 5-((4-chlorophenyl)(5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-trione

Molecular Formula C20H15FN4O4; Yield (%) 88; mp  186°C; IR (KBr): nmax :- 3201 (NH amide), 3090 (N (sec)), 2868 (ArH), 1688,1706 (C=O), 1142 (C-Cl), 1595 (C=N), 2829 (tert. alkane); 1H NMR (300 MHz, DMSO-d6 : 1.96-3.04 (m,d,d, 3H, tert.H), 10.4 (s, 1H, NH), 11.01 (s, 2H, NH),  6.4-7.94 (m, 9H, Ar); 13C NMR (CDCl3) (δ/ppm); 164.4 (C=N), 177.4 (NH-CO-), 70.0, 30.7 (C-C), 23.3, 150.4, 169.3 (barbiturate),  128.8, 131.3, 131.0, 133.0 (Ar-C), 128.5, 127.5, 131.5, 146.5 (Ar-C). Anal. Calc. C, 58.47; H, 3.68; Cl, 8.63; N, 13.64; O, 15.58. Found: C, 58.43; H, 3.61; Cl, 8.60; N, 13.60; O, 15.55 MS: (m/s) 111.0 [C6H4Cl]+, 202.0 [C9H4N3OS]+, 228.0 [C11H6N3OS]+, 253.0 [C13H8N3OS]+, 254.0 [C13H9N3OS]+, 279.0 [C15H9N3OS]+, 305.1 [C17H11N3OS]+, 287.9 [C13H7ClN3OS]+, 313.0 [C15H8ClN3OS]+, 339.0 [C17H10ClN3OS]+, 365.0 [C19H12ClN3OS]+.

 

3d– 5-((3-nitrophenyl)(5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-trione

Molecular Formula C20H15N5O6; Yield (%) 85; mp  172°C; IR (KBr): nmax :- 3207 (NH amide), 3096 (N (sec)), 2874 (ArH), 1695,1711 (C=O), 1348,1527 (NO2), 1602 (C=N), 2835 (tert. alkane); 1H NMR (300 MHz, DMSO-d6 : 2.06-3.47 (m,d,d, 3H, tert.H), 10.8 (s, 1H, NH), 11.21 (s, 2H, NH),  6.9-8.44 (m, 9H,Ar); 13C NMR (CDCl3) (δ/ppm); 164.4 (C=N), 177.4 (NH-CO-), 70.0, 30.7 (C-C), 23.3, 150.4, 169.3 (barbiturate),  128.8, 131.3, 131.0, 133.0 (Ar-C), 121.1, 129.3, 132.2, 147.6, 149.3 (Ar-C). Anal. Calc. C, 57.01; H, 3.59; N, 16.62; O, 22.78. Found: C, 56.97; H, 3.55; N, 16.60; O, 22.73.

3e– 5-((4-hydroxyphenyl)(5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-trione

Molecular Formula C20H16N4O5; Yield (%) 84; mp 166°C; IR (KBr): nmax :- 3209 (NH amide), 3099 (N (sec)), 2878 (ArH), 1697,1715 (C=O), 3510 (0-H), 1605 (C=N), 2839 (tert. alkane); 1H NMR (300 MHz, DMSO-d6 : 1.96-2.95 (m,d,d, 3H, tert.H), 10.08 (s, 1H, NH), 10.81 (s, 2H, NH), 6.6-7.69 (m, 9H,Ar), 10.42 (s, 1H, OH); 13C NMR (CDCl3) (δ/ppm); 164.4 (C=N), 177.4 (NH-CO-), 70.0, 30.7 (C-C), 23.3, 150.4, 169.3 (barbiturate),  128.8, 131.3, 131.0, 133.0 (Ar-C), 115.6, 127.5, 141.0, 155.7 (Ar-C). Anal. Calc. C, 61.22; H, 4.11; N, 14.28; O, 20.39. Found: C, 61.20; H, 4.09; N, 14.23; O, 20.33.

 

3f – 5-(furan-2-yl(5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-trione

Molecular Formula C18H14N4O5; Yield (%) 88; mp  190°C; IR (KBr): nmax :- 3204 (NH amide), 1088 (C-O-C), 730 (furan), 3094 (N (sec)), 2873 (ArH), 1692, 1710(C=O), 1601 (C=N), 2834 (tert. alkane); 1H NMR (300 MHz, DMSO-d6 : 1.97-2.94 (m,d,d, 3H, tert.H), 10.06 (s, 1H, NH), 10.81 (s, 2H, NH), 6.4-7.67 (m, 5H,Ar), 6.77-6.81 (furan m ,3H); 13C NMR (CDCl3) (δ/ppm); 164.4 (C=N), 177.4 (NH-CO-), 68.2, 31.9 (C-C), 21.5, 150.4, 169.3 (barbiturate),  128.8, 131.3, 131.0, 133.0 (Ar-C), 105.9, 110.0, 141.5, 156.0 (furan). Anal. Calc. C, 59.02; H, 3.85; N, 15.29; O, 21.84. Found: C, 59.01; H, 3.80; N, 15.27; O, 21.80.

 

 

Scheme:

                           


RESULT AND DISCUSSION:              

The oxazolones derivatives were synthesized by condensation of various benzaldehydes, hippuric acid, acetic anhydride and sodium acetate under microwave irradiation method. The melting points of the synthesized compounds were checked by the given literature. The compounds 2(a-f) 4-substituted methylene-2-phenyl-1H-imidazol-5(4H)-one, were synthesized by the condensation reaction of oxazolones 1(a-f) with ammonia under microwave irradiation. The purity of compounds was analyzed by TLC using benzene: Ethyl acetate (7:3) as mobile base. The title compounds 3(a-f) 5-((5-oxo-2-phenyl-4,5-dihydro-1H-imidazol-4-yl)methyl)pyrimidine-2,4,6(1H,3H,5H)-triones were synthesized by reaction of 2(a-f) with barbituric acid. The structures of the synthesized compound were confirmed on the basis of spectral analysis. The compound showed absorption band at around 3192 - 3209 (NH amide), 2818 - 2839 (tert. alkane). Further in their H NMR (δ ppm DMSO d6) spectrum the appearance of signal at 1.86 – 3.47 (tertiary H) and  singlets for NH and in 13C NMR appearence of signal near 70.0 and 30.7 (C-C) confirms the formation of compounds. Also Mass spectrum of the compounds showed molecular ion peak corresponding to their molecular formula.

 

Antimicrobial Activity

The compounds were tested in vitro for antibacterial activity against the test organisms E. coli (MTCC 443), P. aeruginosa (MTCC 1688), S. aureus (MTCC 96) and S. pyogenus (MTCC 442) and antifungal activity against the organisms C. albicans (MTCC 227), A. niger (MTCC 282) and A. clavatus (MTCC 1323). ‘Broth Dilution Method’ was used for MIC (Minimal Inhibition Concentration) determination. The data were compared to the standard Ampicillin, Chloramphenicol, Ciprofloxacin and Norfloxacin for bacteria and Nystatin and Greseofulvin for fungi. The results are given in table 1 and 2.

The tested compounds exhibited mild to moderate antibacterial activity against all four strains of bacteria. The compounds 3e and 3b showed 100 µg/mL MBC against S. pyogenus. Other compounds showed MBC ranging from 125 to 250 µg/mL. On comparing the compounds it was observed that the compounds are more active against gram negative ones.

 

The tested compounds exhibited mild antifungal activity against both strains of fungus. The compounds 3b showed 250 µg/mL MFC against A. niger. The compounds 3d showed 250 µg/mL MFC against A. clavatus. Other compounds showed MFC ranging from 500 and above.

 

 

Table 1-In vitro antibacterial activity of synthesized compounds

Compound

Minimal Inhibition Concentration (µg/ml)

E. coli

MTCC 442

P. aeruginosa

MTCC 441

S. aureus

MTCC 96

S. pyogenus

MTCC 443

3a

200

200

125

200

3b

200

200

125

100

3c

200

125

200

125

3d

250

250

250

250

3e

200

200

125

100

3f

200

125

200

125

Ampicillin

100

--

250

100

Chloramphenicol

50

50

50

50

Ciprofloxacin

25

25

50

50

Norfloxacin

10

10

10

10

 

Table 2- In vitro antifungal activity of synthesized compounds

Compound

Minimal Inhibition Concentration (µg/ml)

C. albicans

MTCC 227

A. Niger

MTCC 282

A. clavatus

MTCC 1323

3a

1000

>1000

1000

3b

1000

250

500

3c

>1000

1000

1000

3d

500

1000

250

3e

1000

>1000

1000

3f

500

1000

1000

Nystatin

100

100

100

Greseofulvin

500

100

100

 

 

CONCLUSION:

In conclusion, the proposed methodology (Microwave synthesis) provides a fast, clean, economic and environment benign synthesis of imidazole. Synthesized compounds 3a, 3b, 3c, 3e, 3f showed good activities against bacterial strains and compounds 3b, 3d and 3f showed good activities against fungal strain. The bacterial activities of the compounds are comparable with that of standard drug Ampicillin and fungal activities of compounds against C. albicans are comparable with that of standard drug Greseofulvin.

ACKNOWLEDGMENTS:

The authors acknowledge the financial support of the University Grant Commission, India and Mohanlal Sukhadia University, Udaipur, Rajasthan for providing laboratory and other basic facilities for carrying out experimental work. They thank Sophisticated Analytical Instrumentation Facility (SAIF) Punjab University, Chandigarh for characterization of the synthesized compounds. They also wish to express their gratitude to Microcare Laboratory, Surat, Gujrat in connection with anti-microbial tests.

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Received on 02.08.2016         Modified on 24.08.2016

Accepted on 15.09.2016         © AJRC All right reserved

Asian J. Research Chem. 2016; 9(10):469-474.

DOI: 10.5958/0974-4150.2016.00070.5