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ORIGINAL ARTICLE |
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Year : 2014 | Volume
: 5
| Issue : 4 | Page : 196-201 |
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Synthesis, characterization, antimicrobial, and pharmacological evaluation of some 2, 5-disubstituted sulfonyl amino 1,3,4-oxadiazole and 2-amino-disubstituted 1,3,4-thiadiazole derivatives
Dilipkumar Pal1, Rohit Tripathi2, Desh Deepak Pandey2, Preety Mishra2
1 Department of Pharmaceutical Sciences, Guru Ghasidas Vishwavidyalaya, Bilaspur, Chhattisgarh, India 2 Department of Pharmaceutical Chemistry, KNIMT Faculty of Pharmacy, Sultanpur, Uttar Pradesh, India
Date of Web Publication | 15-Oct-2014 |
Correspondence Address: Dilipkumar Pal Department of Pharmaceutical Sciences, Guru Ghasidas Vishwavidyalaya, Bilaspur, Chhattisgarh - 495 009 India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/2231-4040.143040
The presence of heterocyclic structures in diverse types of compounds, this is strongly indicative of the profound effect like structure exerts on physiologic activity, and recognition of this is abundantly reflected in efforts to find useful synthetic drugs. The search for better pharmacological active drug and the importance of disubstituted 1,3,4-oxadiazole and 1,3,4-thiadiazole as active pharmacophores, prompted us to design, synthesize, characterize, and evaluate a series of differently substituted sulfonyl amino 1,3,4-oxadiazole and 1,3,4-thiadiazole for their potential antimicrobial, analgesic and antiinflammatory activity, respectively. New sulfonyl amino 1,3,4-oxadiazole and 1,3,4-thiadiazole derivatives were synthesized by intramolecular cyclization of thiosemicarbazide in alkaline medium. Reactions were carried out by the reaction between aromatic carbonyl halide and thiosemicarbazide. Keywords: 1,3,3,4-oxadiazole, 4-thiadiazole, semicarbazide, sulphonyl amino 1, thiosemicarbazide
How to cite this article: Pal D, Tripathi R, Pandey DD, Mishra P. Synthesis, characterization, antimicrobial, and pharmacological evaluation of some 2, 5-disubstituted sulfonyl amino 1,3,4-oxadiazole and 2-amino-disubstituted 1,3,4-thiadiazole derivatives. J Adv Pharm Technol Res 2014;5:196-201 |
How to cite this URL: Pal D, Tripathi R, Pandey DD, Mishra P. Synthesis, characterization, antimicrobial, and pharmacological evaluation of some 2, 5-disubstituted sulfonyl amino 1,3,4-oxadiazole and 2-amino-disubstituted 1,3,4-thiadiazole derivatives. J Adv Pharm Technol Res [serial online] 2014 [cited 2023 Mar 30];5:196-201. Available from: https://www.japtr.org/text.asp?2014/5/4/196/143040 |
Introduction | |  |
A fused aromatic ring consists of monocyclic rings that share their connecting bonds forming other aromatic compounds such as oxadiazoles and thiadiazoles with two nitrogen instead of one. These are the azoles with oxygen, or sulfur, and nitrogen separated by one carbon atom. [1] Oxadiazole and thiadiazole derivatives have been evaluated and proved for a wide range of pharmacological, biochemical, clinical uses and applications. [2] Phenyl 1, 3, 4-oxadiazole derivatives are known to have diverse biological activities like antifungal, [3] antibacterial, [4],[5] anticonvulsant, [6],[7],[8] antiinflammatory [9] etc., moreover, 1, 3, 4-thiadiazole derivatives also possess diverse chemical and pharmacological applications such as, antiinflammatory, [10],[11] analgesic, [12] anticonvulsant, [13] antimicrobial, [14] anticancer, [15] antifungal, [16] antiviral, [17] carbonic anhydrates inhibitor, [18] antidepressants, [19] and antioxidant. [20],[21] properties. This property of 1, 3, 4-thiadiazole is particularly due to the presence of = N-C-S moiety. [22]
Materials and methods | |  |
All used chemicals and glass were supplied by (Merck and S.D. Fine Chemicals, Lucknow, Uttar Pradesh, India). Melting point was determined by open capillary tube method. Progress of each step was confirmed by teens learning control (TLC). Purification of compounds was checked by column chromatography and silica gel G (60-120 MESS) and silica gel GF 254 (4:1) for preparation of the TLC plates and spots were seen under iodine vapor and U.V. light chamber (Ramtech Laboratories Product, Chennai, India). Proton nuclear magnetic resonance ( 1 HNMR) Spectra were recorded on a BRUKER DR × 300 MHz instrument) in DMSO-d 6 using (tetramethylsilane) as an internal standard. Chemical shifts (d) were expressed in ppm. The mass spectra were recorded on water OPLC - TQDMS in positive mode electrospray Ionization mass spectrometry spectrophotometer.
Experimental section
Synthesis
General method of synthesis of acid halides I (a-d)
A mixture of substituted carboxylic acid (0.01 mole) and phosphorus pentachloride was taken in a renal blood flow connected with the condenser by means of the adapter. The mixture was heated gently to melt with vigorous shaking at around 50°C, after 30 min excess POCl 3 was distilled out, and the residue (I a-d) was dried well and used for the next reaction.
Synthesis of compound (II a-d)
Added semicarbazide to the respected acid chloride and reflux for 5 h. These programs of the reaction were monitoring by checking the TLC. The excess benzene was distilled out neutralizing with aq.NaHCO 3 .
Synthesis of compound (III a-d)
Then hydrolyze it in the basic medium. Product was dried well and recrystallized from methanol.
Synthesis of compound (IV a-d)
The product was heated with 4-toluene-sulfonyl chloride in dry pyridine keeping the temperature 150°C-160°C for 3 h on a heating mantle to obtained respective oxadiazole. Progress of the reaction was checked by TLC using solvent system (a-c) chloroform: N-Hexane (2:3). Yield 72%, 77%, 70%, and solvent system for (d) was chloroform: Ethyl acetate: Petroleum ether: Methanol (2:1:3:2). Yield 70%.
Synthesis of compound (V a-d)
The mixture of thiosemicarbazide and aromatic substituted carbonyl chloride in the presence of benzene was refluxed for 3-4 h and added to crushed ice. Recrystallized with ethanol.
Synthesis of compound (VI a-d)
A mixture of 2-amino-5-phenyl-1, 3, 4-thiadiazole and aromatic substituted aldehyde was irradiated in a microwave oven for 20 min with 40% power and interval of 30s. After the completion of reaction, ice cold water was added to separate the solid, recrystallized with ethanol. Progress of the reaction was checked by TLC using the solvent system (a-d) ethyl acetate: Chloroform (3:8). Yield 72%, 74%, 78%, 70%.
Synthetic scheme

Derivatives
I-IV {R= (a=-C 6 H 5 ; b=-2-ClC 6 H 4 ; c=-3-ClC 6 H 4 ; d=-3-NO 2 C 6 H 4 )
V-VI {R= (a=-C 6 H 5 ; b=-2-ClC 6 H 4 ; c = 4-NO 2 C 6 H 4 ; d = 4-ClC 6 H 4 ); Ar= (a=-C 6 H 5 ; b=-2-ClC 6 H 4 ; c=-4-NO 2 C 6 H 4 ; d=-4-ClC 6 H 4 )}.
Antibacterial activity
Antibacterial activity of all synthesized derivatives was determined by disc diffusion method (Kirby Baeur method) against two gram positive bacteria namely Staphylococcus aureus and Bacillus subtilis and two gram negative bacteria namely Salmonella More Details sp. and Pseudomonas sp. minimum inhibitory concentration. Those compounds were determined which are showing activity in primary screening standard antibiotics namely ofloxacin was used for comparison.
Pharmacological evaluations
Antiinflammatory activity of 2-amino-disubstituted-1, 3, 4-thiadiazole compounds was done by carrageenan-induced rat paw edema method using diclofenac sodium-30 as a standard drug, and analgesic activity of 2-amino 5-disubstituted-1, 3, 4-thiadiazole derivatives was done by tail flick method using aspirin as a standard drug.
Statistical analysis
One-way ANOVA using Dunnett's t-test was applied for statistical analysis; treatment groups were compared with the control group and the standard drug(s). P <0.05 and P < 0.001 value was considered significant and highly significant, respectively.
Results and discussion | |  |
Physical data of the synthesized compounds are presented in [Table 1] and [Table 2]. The titled compounds 2, 5-disubstituted sulfonyl amino-1, 3, 4-oxadiazole (IV a-d) and 2-amino-disubstituted-1, 3, 4-thiadiazole derivatives were obtained in good yields (VI a-d). The structures were confirmed on the basis of spectral data. | Table 1: Physical data of the synthesized compounds of 2,5-disubstituted sulfonyl amino 1,3,4-oxadiazole
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 | Table 2: Physical data of the synthesized compounds of 2-amino-disubstituted-1,3,4-thiadiazole
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Spectral data
· Compound (IVa): [2-(p-toluene sulfonyl amino-N-(5-phenyl)- [1, 3, 4]-oxadiazole]
Proton nuclear magnetic resonance (D 2 O, d, ppm): 2.1 (s, 3H, J = 2.385), 7.3 (s, 2H, J = 7.44), 7.6 (s, 3H, J = 7.699), 8.0 (s, 1H, J = 7.968), 8.5 (d, 1H, J = 8.688). MASS m/z (%): 424.2 (6), 372.1 (8), 380.9 (8), and 291.3 (10), 263.0 (14), 224.2 (16), 481.9 (30), 444.6 (32), 380.2 (34), 490.8 (48), 223.2 (100)
· Compound (IVb): [2-(p-toluene sulfonyl amino)-N-[5-(2-chloro-phenyl)]- [1, 3, 4]-oxadiazole]
Proton nuclear magnetic resonance (D 2 O, d, ppm): 2.3 (s, 2H, J = 2.369), 7.28 (d, 2H, J = 7.375), 7.44 (s, 2H, J = 7.4855), 7.61 (d, 1H, J = 7.675), 7.98 (s, 1H, J = 8.017), 8.54 (s, 1H, J = 8.567), 8.68 (d, 1H, J = 8.6465). MASS m/z (%): 80.1 (6), 228.6 (6), 468.7 (6), 473.3 (6), and 372.8 (12), 436.7 (16), 471.3 (16), 313.0 (24), 410.9 (26), 330.9 (44), 344.6 (46), 371.8 (46) 293.1 (54), 369.8 (72), 291.2 (100)
· Compound (IVc): [2-(p-toluene sulfonyl amino)-N-[5-(4-chloro-phenyl) - [1, 3, 4]-oxadiazole]
Proton nuclear magnetic resonance (D 2 O, d, ppm) 2.3 (s, 4H, J = 2.378), 7.3 (d, 4H, J = 7.344) 7.64 (d, 2H, J = 7.672), 8.0 (t, 2H, J = 8.062), 8.57 (t, 1H, J = 8.6106), 8.72 (d, 2H, J = 8.763), MASS m/z (%): 318.7 (8), 378.8 (10), 470.1 (10), 436.6 (14), 248.6 (15), 414.4 (18), 344.4 (21), 331.0 (24), 274.8 (26), 410.9 (26), 80.1 (28), 332.7 (34), 291.0 (100)
· Compound (IVd): [2-(p-toluene sulfonyl amino)-N-[5-(3-nitro-phenyl)] - [1, 3, 4]-oxadiazole]
Proton nuclear magnetic resonance (D2O, d6, d, ppm) 2.1(s, 2H, J = 2.359), 7.23 (s, 2H, J = 7.322), 7.55 (s, 1H, J = 7.6704), 7.93 (s, 2H, J = 8.059), 8.52 (s, 2H, J = 8.587), 8.67 (s, 1H, J = 8.647), MASS m/z (%): 194.7 (6), 301.7 (6), 497.8 (7), 274.8 (8), 419.0 (8), and 387.8 (10), 348.6 (12), 378.8 (12), 448.5 (13), 248.5 (14), 332.6 (14), 306.6 (16), 468.3 (19), 410.9 (38), 80.1 (100)
· Compound (VIa): [2-aminobenzyl-5-phenyl-1, 3,
4-thiadiazole]
Proton nuclear magnetic resonance (DMSO, d 6 , d, ppm): 0.42(m, 1H, J = 7.5), 0.93 (m, 1H, J = 7.5), 1.00 (t, 1H, J = 7.4); mass m/z (%): 166.1 (08), 179.2 (10), 237.5 (10), 338.0 (10), 279.0 (14), 500.1 (14), 610.9 (14), 301.2 (18), 372.1 (18), 413.3 (18), 561.0 (18), 586.4 (18), 661.2 (18), 453.1 (22), 378.8 (24), 569.1 (26), 712.6 (26), 178.2 (30), 428.1 (34), 523.0 (38), 685.4 (38), 664.3 (48), 452.1 (94), 663.3 (100)
· Compound (VIb): [2-amino (2-chlorobenzyl)- 5(2-chlorophenyl)-1, 3, 4-thiadiazole]
Proton nuclear magnetic resonance (DMSO, d 6 , d, ppm): 1.0 (d, 1H, J = 7.680), 2.0 (d, 2H, J = 7.637), 2.44 (m, 2H, J = 7.520), 2.56 (m, 2H, J = 7.52), 3.06 (m, 3H, J = 7.60), 4.27 (m, 4H, J = 7.549), 4.36 (m, 4H, J = 7.594), 5.64 (m, 5H, J = 7.575), 6.33 (d, 6H, J = 7.807), 7.61 (m, 7H, J = 7.599); mass m/z (%): 458.6 (10), 356.7 (14), 633.6 (14), 178.2 (20), 335.5 (22), 631.6 (24), 354.7 (100)
· Compound (VIc): [2-amino-(4-nitrobenzyl)- 5-(4-nitropheny)-1, 3, 4-thiadiazole]
Proton nuclear magnetic resonance (DMSO-d 6 , d, ppm): 0.33 (s, 1H, J = 6.152), 0.46 (d, 1H, J = 7.999), 1.00 (d, 1H, J = 7.739), 1.44 (d, 1H, J = 8.283), 1.83 (s, 1H, J = 10.112), 3.67 (d, 3H, J = 8.446), 3.95 (d, 3H, J = 8.177); mass m/z (%): 365.9 (10), 407.1 (10), 446.2 (10), 505.0 (10), 701.2 (12), 741.2 (12), 407.9 (14), 576.3 (14), 212.1 (16), 426.7 (20), 544.4 (22), 515.0 (24), 530.0 (34), 424.7 (70), 422.7 (100)
· Compound (VId): [2-amino- (4-chlorobenzyl) -5-(4-chlorophenyl)-1, 3, 4-thiadiazole]
Proton nuclear magnetic resonance (DMSO-d 6 , d, ppm): 0.03(s, 1H, J = 8.340), 0.18 (s, 1H, J = 9.873), 0.76 (m, 1H, J = 7.898), 1.00 (d, 1H, J = 7.710), 1.78 (m, 1H, J = 7.540); mass m/z (%): 458.6 (10), 356.7 (14), 633.6 (14), 178.2 (20), 335.5 (22), 631.6 (24), 354.7 (100).
Evaluation of antibacterial activity
Antibacterial activities of all synthesized compounds were determined by disc diffusion method. Results are exhibited in [Table 3] and [Figure 1]. Compounds IVa and IVb exhibited good activity, and IVc and IVd showed moderate activity as compared with standard drug Ofloxacin. | Figure 1: Zone of inhibition by different compounds against different bacteria
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Pharmacological evaluation
Results are represented in [Table 4] and [Table 5]. Compounds VIb and VIc exhibited good antiinflammatory activity as compared with standard drug diclofenac-30, while VIc shows good analgesic activity as compared with standard drug aspirin. | Table 4: Antiinflammatory activity of the synthesized compound (2-amino-5-disubstituted-1,3,4-thiadiazole derivatives) by carrageen an induced rat paw edema method showing percentage of inhibition
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 | Table 5: Analgesic activity of the synthesized compound (2-amino5-disubstituted-1,3,4-thiadiazole derivatives) by tail flick method (values obtained)
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Conclusion | |  |
A series of 2-amino-disubstituted-1, 3, 4-thiadiazoles ando2, 5-disubstituted-phenyl 1, 3, 4-oxadiazoles was synthesized with good yields, and their structures were elucidated by spectral data. All the compounds show good pharmacological activities. Compounds IVa and IVb exhibited good antimicrobial activity and IVc, IVd showed moderate microbial activity as compared with a standard drug ofloxacin. Compounds VIb and VIc exhibited good antiinflammatory activity as compared with standard drug diclofenac-30, while VIc shows good analgesic activity in comparison to aspirin used as standard drug.
Acknowledgments | |  |
One of the authors is t hankful to the head of the department (Pharmaceutical Chemistry), Faculty of Pharmacy, K.N I M T, Sultanpur for necessary support. We also acknowledge our regard to SAIF Laboratory of Central Drug Research Institute (CDRI), Lucknow for providing spectra of compounds prepared.
References | |  |
1. | Geeta M, Arvind KS, Kshtiz J. Review article on 1, 3, 4-Thiadiazole derivaties and it′s pharmacological activities. Int J Chem Tech Res 2011;3:1380-93. |
2. | Tawfeeq FR, Al-Auqbi NT, Al-Khalidy T. Inhibitory effect of oxadiazooles and thiadiazoles in vitro on serum alkaline phosphates′ enzyme of pregnant woman. Am J Plant Sci 2012;11:1. |
3. | Maslat AO, Abussaud M, Tashtoush H, Al-Talib M. Synthesis, antibacterial, antifungal and genotoxic activity of bis-1,3,4-oxadiazole derivatives. Pol J Pharmacol 2002;54:55-9. |
4. | Chawla R, Arora A, Parameswaran MK, Chan P, Sharma D, Michael S, et al. Synthesis of novel 1,3,4-oxadiazole derivatives as potential antimicrobial agents. Acta Pol Pharm 2010;67:247-53. |
5. | Mehta AN, Yadav J, Desai KR. Eco-Friendly synthesis of novel fluorine containing 1, 3, 4-oxadiazole as antibacterial and antifungal agents. Asian J Res Chem 2013;6:486-9. |
6. | Sudha BS, Shashikanth S, Khanum SA, Sriharsha SN. Synthesis and pharmacological screening of 5- (4-Aroyl)-aryl oxy methyl-2-thio -1, 3, 4-oxadiazole. Indian J Pharm Sci 2003; 65; 5: 465-70. |
7. | Bhatnacar S, Kamthan D, Mehra SC, Tandan SK. Synthesis of some new N3-substituted hydantoins as potential anticonvulsant agents. Indian J Pharm 1986;18:35-238. |
8. | Singh A, Rana AC. Synthesis and anticonvulsant activity of 1-[(4, 5-dihydro-5-phenyl-3-(phenylamine) pyrazol-1-yl)] ethanone derivatives. J Chem Pharm Res 2010;2:05-511. |
9. | Sahoo BM, Ravi Kumar BV, Prasanna KB. Synthesis, characterization and biological evaluation of novel oxadiazole derivatives. Int J Pharm Sci Res 2011;2:344-50. |
10. | Schenone S, Brullo C, Bruno O, Bondavalli F, Ranise A, Filippelli W, et al. New 1,3,4-thiadiazole derivatives endowed with analgesic and anti-inflammatory activities. Bioorg Med Chem 2006;14:1698-705. |
11. | Rostom SA, el-Ashmawy IM, Abd el Razik HA, Badr MH, Ashour HM. Design and synthesis of some thiazolyl and thiadiazolyl derivatives of antipyrine as potential non-acidic anti-inflammatory, analgesic and antimicrobial agents. Bioorg Med Chem 2009;17:882-95. |
12. | Singh AK, Bose S, Singh UP, Jana S, Shukla R, Singh V. Synthesis and biological activity of some new thiadiazole derivative. Technol Pharm Res 2009;2:133-7. |
13. | Chapleo CB, Myers PL, Alan CB. Smith IF. Tulloch DS. Walter. Substituted 1, 3, 4-thiadiazoles with anticonvulsant activity. Guanidine′s. J Med Chem 1987;30:951-4. |
14. | Mulay A, Mangesh G, Nikalje AP. Exploring potential of 4-thiazolidinone: A brief review. Int J Pharm Sci 2009;1:47-64. |
15. | Kumar D, Maruthi Kumar N, Chang KH, Shah K. Synthesis and anticancer activity of 5-(3-indolyl)-1,3,4-thiadiazoles. Eur J Med Chem 2010;45:4664-8. |
16. | Matysiak J, Malinski Z. 2-(2,4-Dihydroxyphenyl)-1,3,4-thiadiazole analogues: Antifungal activity in vitro against Candida species. Bioorg Khim 2007;33:640-7.  [ PUBMED] |
17. | Chen Z, Xu W, Liu K, Yang S, Fan H, Bhadury PS, et al. Synthesis and antiviral activity of 5-(4-chlorophenyl)-1,3,4-thiadiazole sulfonamides. Molecules 2010;15:9046-56. |
18. | Bülbül M, Saraçoglu N, Küfrevioglu OI, Ciftçi M. Bile acid derivatives of 5-amino-1,3,4-thiadiazole-2-sulfonamide as new carbonic anhydrase inhibitors: Synthesis and investigation of inhibition effects. Bioorg Med Chem 2002;10:2561-7. |
19. | Clerici F, Pocar D, Guido M, Loche A, Perlini V, Brufani M. Synthesis of 2-amino-5-sulfanyl-1,3,4-thiadiazole derivatives and evaluation of their antidepressant and anxiolytic activity. J Med Chem 2001;44:931-6. |
20. | Pal D, Mitra S. A preliminary study on the in vitro antioxidant activity of the stems of opuntia vulgaris. J Adv Pharm Technol Res 2010;1:268-72.  [ PUBMED] |
21. | Nayak AK, Pal D, Pany DR, Mohanty B. Evaluation of Spinacia oleracea L. leaves mucilage as an innovative suspending agent. J Adv Pharm Technol Res 2010;1:338-41.  [ PUBMED] |
22. | Oruç EE, Rollas S, Kandemirli F, Shvets N, Dimoglo AS 1,3,4-thiadiazole derivatives. Synthesis, structure elucidation, and structure-antituberculosis activity relationship investigation. J Med Chem 2004;47:6760-7. |
[Figure 1]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
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