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Review of Biological Activities of Hydrazones Indonesian J. Pharm. Vol. 23 No. 4 : 193 – 202 ISSN-p : 0126-1037 Review Article REVIEW OF BIOLOGICAL ACTIVITIES OF HYDRAZONES Md. Rahmat Ali1, Akranth Marella1, Md. Tauquir Alam1, Ruksar Naz1, Mymoona Akhter1, Md. Shaquiquzzaman1, Rikta Saha1, Omprakash Tanwar1, Md. Mumtaz Alam1*, Jyoti Hooda2 1Department of ABSTRACT Pharmaceutical Chemistry, Hydrazones possess an azomethine –NHN=CH group and Faculty of Pharmacy, are considered as derivatives of aldehydes and ketones in which Jamia Hamdard, New Delhi the oxygen atom has been replaced by the NNH2 functional 110062, India. group. These are widely studied molecules owing to their ease of 2CHRD- Competitive and preparation and diverse pharmacological potential. This has led Scientific Intelligence researchers to synthesize different heterocyclic compounds (CSI), WNS Global bearing hydrazones. Medicinal chemists across the world have Services (P) Ltd, Gurgaon done immense work on hydrazones and developed agents with 122002, India. better activity and low toxicity profiles. Following different Submitted: 10-08-2012 synthetic protocols and through proper SAR studies differently Revised: 14-09-2012 substituted hydrazones have been developed and found to be Accepted: 13-10-2012 active against different pharmcological targets. They are known to possess different biological activities viz. antimicrobial, anti- *Corresponding author inflammatory, anticancer, antimalarial etc. These observations Md. Mumtaz Alam have been guiding for the development of new hydrazones that possess varied biological activities. The review aims at Email : highlighting the diverse biological activities of hydrazones. [email protected] Key words: Azomethine, Hydrazones, Pharmacological Potential INTRODUCTION The C=N bond of hydrazone and Hydrazones are a class of organic terminal nitrogen atom containing a lone pair compounds which possess the structure of electron is responsible for the physical and R1R2C=NNH2. They are related to ketone and chemical properties. The C-atom in hydrazone aldehyde in which oxygen has been replaced has both electrophilic and nucleophilic with NNH2 group. These azometine - character and both the N-atoms are NHN=CH- proton constitute an important nucleophilic although the amino type nitrogen class of compounds for new drug development. is more reactive. Due to these properties Hydrazones are formed by the reaction of hydrazones are widely used in organic hydrazine or hydrazide with aldehydes and synthesis. The chemical structure of hydrazone ketones. They act as reactants in various derivatives were showed in figure 1-4. important reactions such as hydrazone iodination, Shapiro reaction and Bamford- BIOLOGICAL ACTIVITY Stevans reaction to form vinyl compounds. Antimicrobial activity They act as intermediate in Wolff-Kishner The overuse of chemicals against various reaction. Hydrazones can also be synthesized infectious diseases has led to rapid emergence by the Japp-Klingemann reaction (from β- of resistivity against different bacteria. ketoacids or β-ketoester’s and aryldiazonium Therefore, the search for antimicrobials is a salts). The N,N’-dialkyl type of hydrazones can never ending task. Consequently, there has be hydrolysed, reduced and oxidized this leads been an immense research on hydrazones as to the formation of amines by reduction of N- antibacterial agents. Sharma et al. (2011) N bond. The C=N double bond in hydrazones reported the antibacterial activity of hydrazine are important compounds in drug design as derivatives (1) against various bacterial strains. they act as ligands for metal complexes, Hydrazine derivatives (2, 3) synthesized by organocatalysis and synthesis of organic Jubie et al. (2010) are promising antibacterial compounds. agents. Ozkay et al. (2010) synthesized novel benzimidazole derivatives bearing hydrazone Volume 23 Issue 4 (2012) 193 Activities of Hydrazones moiety (4) and evaluated their antibacterial virulent H37Rv strain. Few hydrazone activity against different bacterial strains. Novel derivatives (27) synthesized by Raja et al. (2010) chloropyrrole derivatives of aroylhydrazone (5) have been screened and reported to have MIC developed by Rane et al. (2010) have been of 6.3µg/mL. 4-hydroxy-8-trifluromethyl- evaluated for antibacterial activity against quinoline derivatives (31) with a MIC of different bacterial strains. Edress et al. (2010) 0.625µg/mL have been reported by Thomas et synthesized some hydrazonoyl substituted al. (2011). Vavrikova et al. (2011) synthesized pyrimidinones (6, 7) and evaluated their fluorine-containing hydrazones (32) with a MIC antibacterial activity. Govindasami et al. (2011) of 0.5µg/mL and a selectivity index of 1268.6 synthesized vanillin based hydrazine derivatives Pavan et al. (2010) synthesized some hydrazines (8, 9) and reported their antibacterial ( 35 ) with promising results. Ferrocenyl activity specifically against Staphylococcus aureus hydrazones (38, 39) with a MIC of 0.75 and and Pseudomonas aeruginosa. Ajani et al. (2010) 0.7µmol/L have been reported by Maguene et have reported the antibacterial activity of al . (2011) Mahajan et al. (2011) synthesized 2-quinoxalinone-3-hydazine derivative (12) ferrocene-based hydrazone derivatives (43) against different bacterial strains. Lee et al. with significant potential. Eswaran et al. (2010) (2012) synthesized various hydrazones (13, 14) synthesized hydrazones (44) with a MIC of as selective inhibitors of Staphylococcus aureus β- 6.25µg/mL. Jordao et al. (2011) synthesized ketoacyl carrier proteinsynthase III. The hydrazone derivatives (45) with antitubercular compound was found to have an MIC of 1- activity. The compound is reported to have 2µg/mL. Aryloxyacetic acid hydrazide (15) MIC of 2.5µg/mL. Fungal species are known having promising antibacterial activity with to cause many superficial and systemic MIC of 4.1-16.5µg/mL against an array of infections in humans, plants as-well-as bacterial strains has been reported by Wahab et livestock. Hydrazone derivatives (49) al. (2012). Rasras et al. (2010) synthesized synthesized by Ozdemir et al. (2010) after being various cholic acid based hydrazones (22) and screened against different Candida spp have been screened them as antibacterials. The best reported to have promising antifungal potential. compound among the series is reported to have Viruses are obligate parasites which MIC of 2µg/mL and 3.9µg/mL against require cellular machinery of the host to Escherichia faecalis and Escherichia coli. Anthra- prosper. They are capable of causing immense quinone based hydrazones (23) synthesized by harm to host. Hydrazone derivatives (53, 54) Gouda et al. (2010) are reported to have promi- synthesized by Jin et al. (2010) have been sing bacteriostatic activity against P. auriginosa. reported to have EC50 value of 0.6 and 0.4µM Kumar et al. (2010) synthesized various respectively against HIV1-CA. benzyledine-hydrazides (24) and reported their bactericidal activity against S. aureus. The Analgesic and Anti-inflammatory activity agent is reported to have a MIC of 1.5µM/mL. Much work has been done describing the Abdel-Wahab et al. (2011) synthesized different analgesic and anti-inflammatory potential of hydrazone bearing imidazoles (25). The hydrazides. Harnandez et al. (2012) reported synthesized compounds were screened for their analgesic and anti-inflammatory activity of antibacterial activity against numerous bacterial furoxanyl-N-acylhydrazones (55, 56). Rajitha et strains. Vijesh et al. (2010) synthesized 2,4- di- al. (2011) evaluated the anti-inflammatory substituted thiazoles (26). The compound has a activity of some aryl hydrazones (58) and got MIC value ranging between 1.6µg/mL and good results. Moldovan et al. (2011) synthesized 3.1µg/mL when tested against different strains. various hydrazone derivatives (60) and reported Tuberculosis is a chronic infection them to have promising in-vivo anti-inflamma- caused by different strains of Mycobacterium tory activity. El-Sayed et al. (2011) synthesized tuberculosis. The bacterium affects almost any hydrazone derivatives (62) with selective organ but the favorite site is lung. The activity COX-2 inhibition. The compound is reported of the newer agents is mostly tested against to have an ED50 value of 0.2 mmol/Kg. 194 Volume 23 Issue 4 (2012) Md. Rahmat Ali, et al. Figure 1. Chemical structure of hydrazone derivatives no.1-42 Benzo-thiophene derivatives (66) with with potent activity against HL-60 leukaemia inhibition of 50.2% have been developed by and 518A2 melanoma. Acylhydrazones (79) by Isloor et al. (2010). Cui et al. (2010) have been reported to have potent activity against the human Anticancer activity promyelocytic leukemic cells (Hl-60). Copper Cancer is a lethal group of diseases with based hydrazone derivatives (82) are reported a high level of penetrating potency affecting to act against integrin β4 in H322 lung almost every organ of the body. Al-Said et al. carcinoma cell lines by Fan et al. (2010). (2011) synthesized compounds (67) active Palladium based hydrazones (86) by Abu- against human breast cancer cell lines MCF7. Surrah et al. (2010) have been reported to be Hassan et al. (2011) synthesized pyrazole based active against human head and neck squamous hydrazone derivatives (69) with potential to carcinoma cell lines SQ20B and SCC-25. 2- treat breast carcinoma. Kendall et al. (2012) phenylindole based hydrazone (87) synthesized evaluated some derivatives (70) as PI3K p110α by El-Nakkady et al. (2012) have been inhibitors. P13K are signaling
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