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Journal of Chemical and Pharmaceutical esearch ISS o: 0975-7384 CDE(USA): JCPC5 J. Chem. Pharm. es., 2011, 3(6):687-692 Synthesis, Characterisation and Antimicrobial study of some ew Isatins Derivatives Bhavesh athani 1, Kishor S Pandya 1, Manish M Jeni 1, Ashok Prasad 2 1 Department of Chemistry, Sir P.T. Science College, Modasa, Gujarat, India 2 Zydus Cadila ealthcare Ltd, Baroda, Gujarat, India ABSTACT Some new -[3-(2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide (III) have been synthesised from different isatin derivatives (I) by condensing with -[3- (ydrazinocarbonyl) benzyl] benzamide (II). Their chemical structures have been confirmed by I, 1 M, Mass and by elemental analysis. Investigation of antimicrobial activity of compounds was done by the disk diffusion technique. Among the compounds tested, the compound with 5-Cl, 5-I substitution showed the most favourable antimicrobial activity. Keywords: Isatin, Benzamide hydrazone, Microbial, Antibacterial and Antifungal. ITDUCTI It is evident from literature, that isatin derivatives are known to be associated with broad spectrum of biological activity like antibacterial[1], anti-inflammatory [2], analgesic[3], antiviral[4], antifungal[5], antitubercular[6] and antidepressant[7]. Isatin hydrazone have been reported to possess anticonvulsant [7] activity also. In view of these fact prompted us to synthesize some new -[3-(2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide (III). All the synthesized compounds were screened for their in vitro anti-bacterial and anti-fungal activity. EXPEIMETAL SECTI All the melting points were determined by open capillary using V-Scientific Melting Point apparatus and are uncorrected. Purity of compounds was checked by TLC on silica Gel-coated plates. I spectra were recorded in KBr on FTI Prestige-21 Simadzu spectrophotometer. 1 M spectra were recorded on 500 Mz Bruker using CDCl 3 /MeD and Mass spectra were recorded on using EI-MS mode. Elemental analysis was performed on Perkin-Elmer Series 2400. 687

2 Cl 3 CC() 2 2 -Cl a 2 S 3 Scheme-I C= 2 S 4 a C b Scheme-II I + 2 S 4 C a SCl 2 CCl b 2 2 2 C 2 Scheme-III III 688

C 2 I + Et II C 3 C III Synthesis of Isatin (Indole-2, 3-diones): (Ia-h) The different isonitrasoacetinilides (b) were synthesized from the respective aromatic amines (a) viz. on reaction with chloralhydrate and hydroxylamine hydrochloride. Each of isonitrasoacetinilides (b) was subjected to a dehydrative cyclization using sulphuric acid (d 1.84) to yield the corresponding substituted isatin (I). All these isatin thus prepared were identified by I and their physical constant reported in the literature [9]. As shown in Scheme-I. Synthesis of -[3-(ydrazinocarbonyl) benzyl] benzamide: (II) As the literature serve the synthesis of -[3-(ydrazinocarbonyl) benzyl] benzamide by the process [8]. (a) Take -ydroxymethyl benzamide (0.1mol) and benzoic acid (0.1mol) was dissolved in conc.sulfuric acid (50ml). Stir it overnight on mechanical stirrer after completion of reaction, poured into crushed ice and stirred it for 30min and filter the reaction mass and wash with cold water. ecrystalised in methanol to get compound (a). (b) Take compound (a) (0.3mol) in carbon tetrachloride (50ml) and slowly add thionyl chloride (0.5mol), and was heat up to reflux and maintain for 3hrs, after distillation of solvent residue i.e., compound (b) was use for next step without purification. Take above compound (b) and slowly add hydrazine hydrate (0.3mol) at 0-5 0 C temperature and was stirred for 60 min. Solid materials filtered and wash with 10% ac 3 solution. Purified in methanol to obtain pure crystalline compound (II). As shown in Scheme-II. Synthesis of -[3-(2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIa-h) (General Procedure) A mixture of equimolar quantity of isatin derivatives (0.01mol) I and -[3- (hydrazinocarbonyl)benzyl] benzamide (0.01mol) II, was dissolved in ethanol with add 2-3 drops of glacial acetic acid and refluxed for 3-4h.The reaction mixture was cooled and further cool it up to 0-5 0 C and filter it and recrystalised from hot ethanol[10]. As shown in Scheme-III. 689

Synthesis of -[3-(2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIa) I (KBr) cm -1 : 3217.27(), 1691.57(C=), 1672.28(C=), 1620.21(C=), 1 M (CDCl 3 /MeD) ppm: 4.704(2, s,-c 2 ), 6.919-7.412(12, m, Ar), 7.453 (1, s,-), MS m/z: 399.2(M + ) Synthesis of -[3-(5-Chloro-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIb) I (KBr) cm -1 : 3228.84 (), 1714.72 (C=), 1699.29 (C=), 1622.13 (C=), 586.36(C-Cl) 1 M (CDCl 3 /MeD) ppm: 4.713(2, s,-c 2 ), 6.919-7.351(11, m, Ar), 7.414(1, s,-), MS m/z: 433.9(M + ) Synthesis of -[3-(5-Bromo-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIc) I (KBr) cm -1 : 3251.98(), 1703.14(C=), 1678.07(C=), 1616.35(C=), 648.08(C-Br), 1 M (CDCl 3 /MeD) ppm: 4.707(2, s,-c 2 ), 6.917-7.419(11, m, Ar), 7.453(1, s,-), MS m/z: 477.1(M + ) Synthesis of -[3-(5-Methyl-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIId) I (KBr) cm -1 : 3251.98(), 1697.36(C=), 1678.07(C=), 1629.85(C=), 2922.19(-C 2 ), 1 M (CDCl 3 /MeD) ppm: 2.305(3, s,-c 3 ), 4.701(2, s,-c 2 ), 6.919-7.412(11, m, Ar), 7.453(1, s,-), MS m/z: 413.2(M + ) Synthesis of -[3-(5-Flouro-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIe) I (KBr) cm -1 : 3209.55(), 1714.72(C=), 1693.50(C=), 1631.78(C=), 1271.09(C-F), 1 M (CDCl 3 /MeD) ppm: 4.714(2, s,-c 2 ), 6.919-7.419(11, m, Ar), 7.453(1, s,-), MS m/z: 417.2(M + ) Synthesis of -[3-(5-itro-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIf) I (KBr) cm -1 : 3167.12(), 1707.00(C=), 1674.21(C=), 1625.99(C=), 1342.46 (C- 2 ), 1 M (CDCl 3 /MeD) ppm: 4.705(2, s,-c 2 ), 6.919-7.418(11, m, Ar), 7.455(1, s,-), MS m/z: 444.2(M + ) Synthesis of -[3-(5-Iodo-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIg) I (KBr) cm -1 : 3253.91(), 1701.00(C=), 1637.56(C=), 1612.49(C=), 578.64(C-I), 1 M (CDCl 3 /MeD) ppm: 4.707(2, s,-c 2 ), 6.918-7.414(11, m, Ar), 7.453(1, s,- ), MS m/z: 524.8(M + ) Synthesis of -[3-(7-Chloro-2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide: (IIIh) I (KBr) cm -1 : 3172.90(), 1712.79(C=), 1647.21(C=), 1622.13(C=), 582.50(C-Cl), 1 M (CDCl 3 /MeD) ppm: 4.714(2, s,-c 2 ), 6.914-7.414(11, m, Ar), 7.453(1, s,-), MS m/z: 433.2(M + ) 690

Table 1. Physical data and elemental analysis of synthesized compound (IIIa-h) Sr o MP ( 0 C) Molecular Formula (MF) Molecular Weight (MW) Yield (%) IIIa 259-260 0 C C 23 18 4 3 398.41 81 IIIb 5-Cl 284-286 0 C C 23 17 4 3 Cl 432.86 90 IIIc 5-Br 280-282 0 C C 23 17 4 3 Br 477.31 94 IIId 5-C 3 248-250 0 C C 24 20 4 3 412.44 94 IIIe 5-F 290-292 0 C C 23 17 4 3 F 416.40 88 IIIf 5-2 296-297 0 C C 23 17 5 5 443.41 87 IIIg 5-I 262-264 0 C C 23 17 4 3 I 524.31 79 IIIh 7-Cl 283-285 0 C C 23 17 4 3 Cl 432.86 78 Elemental analysis Found (Calc.) %C % % 69.02 4.11 14.04 (69.34) (4.55) (14.06) 63.29 3.32 12.36 (63.82) (3.96) (12.94) 56.93 3.09 11.48 (57.88) (3.59) (11.74) 69.42 4.58 12.97 (69.89) (4.89) (13.58) 65.89 3.99 13.24 (66.34) (4.11) (13.45) 62.19 3.70 15.33 (62.30) (3.86) (15.79) 52.48 3.24 10.29 (52.69) 63.16 (63.82) (3.27) 3.36 (3.96) (10.69) 12.50 (12.94) In Vitro Antimicrobial Activity Evaluation of antibacterial (3-bacteria) and antifungal (2-fungi) activities was done by the disk diffusion technique 12. The microorganisms used were purchased from (1) -broth i.e. utrient broth medium (Titan Biotech Ltd., Delhi). (2) Sabouraud's dextrose broth medium (Titan Biotech Ltd., Delhi). (3) Antibacteriological grade Agar-Agar (Qualigens-Glaxo, Mumbai). The tested compounds solution were prepared in dimethylformamide (DMF) and evaluated them for their in vitro antibacterial and antifungal activity against Baccillus subtillis CIM 2250, Staphylococcus aureus CIM 2079, Escherichia coli CIM 2109, Aspergillus niger ICM 501 and Candida albicans ICM 7431, respectively. All bacteria were grown on Mueller-inton agar (i-media) plates (37 0 C, 24h) and fungi were grown on sabouraud dextrose agar (i-media) plates (26 C, 48-72h). The results were established by the presence of clear zone of inhibition around the active compounds. Table 2. In Vitro antimicrobial activity of -[3-(2-oxo-1, 2-dihydro-indol-3-ylidene-hydrazinocarbonyl) benzyl] benzamide (IIIa-h) Compound Code E-coli B-Subtillis S-Aureus S-Cerevisiae A-niger IIIa ++ ++ + ++ ++ IIIb 5-Cl ++ ++ + ++ + IIIc 5-Br ++ ++ + ++ + IIId 5-C 3 ++ + ++ + + IIIe 5-F + ++ ++ ++ + IIIf 5-2 + + ++ ++ + IIIg 5-I ++ ++ + ++ ++ IIIh 7-Cl ++ + + ++ + *Effectively was classified in to three zones on the bases of the diameter of zone of inhibition + + + : Most effective + + : Moderate effective + : Slightly effective - : on effective 691

ESULTS AD DISCUSSI As many as new eight compounds were synthesized by adopting similar above procedure and then characterized by their physical, analytical and spectral data. The details of some of the representative compounds are given in the experimental section. Their physical and elemental analysis data are presented in Table 1. All the synthesized compounds were tested for in vitro antimicrobial activity by the disk diffusion technique. The results are summarized in Table 2 that includes the activity of reference compound Gentamicine. The tested compounds exhibited mild to moderate antibacterial activity against all three strains of bacteria. The compounds, IIId, IIIe and IIIf tested against S.aureus, showed highest activity. It has also been observed that compounds, IIIa, IIIb, IIIc, IIIe and IIIg against B.subtills. All synthesized compounds were tested for in vitro antimicrobial activity by the disk diffusion technique. The results are summarised in Table 2 that includes the activity of reference compound Gentamicine. The antifungal of the compounds was studied for the two pathogenic fungi. Amphotericin B was used as reference for inhibitory activity against fungi. It was observed that compounds IIIa, IIIb, IIIc, IIIe, IIIf, IIIg and IIIh had highest activity S-Cerevisiae and IIIa and IIIg showed good activity against A.niger. CCLUSI The antimicrobial study revealed that substitution in the 5 th position of isatin with chlorine, bromine, iodine or fluorine produced more active compounds in a series. Acknowledgement The authors are very much thankful to the Principal, Sir P.T.Science College, Modasa for providing necessary facility during research work. The authors thankful CSMCI, Bhavnagar for 1 M spectral analysis facility provided. EFEECES [1] B athani, K S Pandya, M M Jeni and M Patel. Der Pharma Chemica, 2011, 3(4), 367-372. [2] V Alagarsamy and K V amseshu. Pharmazie.2003, 58,233-236. [3] S K Sridhar and M Sreenivasulu. Indian drugs.2001, 38,531-534. [4] S Pandeya, D Sriram, G ath and E DeClercq. Synthesis. Eur.J.Pharm.Sci.1999, 9, 25-31. [5] S Verma and W L obles. J.Pharm.Sci.1975, 69,881-882. [6] V Tran, Q D guyen and V Le. Tap.Chi.Dou oc.2002, 8, 15-17. [7] F D Popp, Parson and B E Donigan. J.Pharm.Sci.1980, 69, 1235-1237. [8] V K Pandey, V D Gupta, M Upadhayay, V K Singh and M Tandon. Indian Journal of Chemistry, 2005, 44,158-162. [9] C S Marvel and G S eirs. rganic Synthesis Collective Vol-I. 2 nd Edition. John Wiley & Sons, ew York.1941, 423. [10] For testing antimicrobial agent in agar media. In: Corian V (Ed) Antibiotics in Laboratory Medicine. 5 th ed. Williams and Wilkins, Baltimore.1991, 1-16. 692