Short communication Synthesis and study of 1-ethyl-3-carbohydrazide and 3-[1-oxo-2- hydrazino-3-{p-toluenesulfon}]quinolone derivatives against bacterial infections Nivedita Srivastava * , Anil Kumar Department of Applied Chemistry, Faculty of Engineering and Technology, M.J.P. Rohilkhand University, Bareilly 243006, U.P., India article info Article history: Received 21 March 2013 Received in revised form 20 June 2013 Accepted 24 June 2013 Available online 9 July 2013 Keywords: Quinolone Fluoroquinolone Hydrazine Sulfonamide Antibacterial Broad spectrum abstract We have synthesized newer series of quinolone derivatives substituted with hydrazine group (6aee) and sulfonamide group (7aee). These compounds were screened for antibacterial activity. All these com- pounds were fully characterized by spectroscopic means and elemental analysis. From minimum inhibitory concentration (MIC) data, it has been observed that all the synthesized compounds exhibited good antibacterial activity in vitro. Ó 2013 Elsevier Masson SAS. All rights reserved. 1. Introduction Urinary tract infection is most common disease in human body. More than 150 millions cases are reported per year worldwide [1]. UTI infection is bacterial infection which affects urinary tract path of the body. If it is not treated in time, bacteria travel to the urethra and multiply, causing kidney infection [2]. Urinary tract infection is more common in ladies as the urethra part of female is shorter than male [3]. UTI is a pathogenic infection and is becoming resistant to all available antibiotics. The most responsible bacterium for UTI is gram negative bac- teria, which belongs to the family Enterobacteriaceae. Gram nega- tive members of this family are Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa. Gram positive bacteria viz Staphylococcus sp. is also responsible for UTI [4,5]. Quinolone is group of synthetic compounds with potent antimicrobial activity and is used orally and parentally in wide variety of infectious disease [6e8]. Our aim is to synthesize newer compounds which may prove to be more potent towards these pathogenic infections and thus inhibit or control the urinary tract infection. Quinolones [9] are chemotherapeutic gyrase or topoisomerases-II inhibitors, eradi- cating bacteria by interfering with DNA replication. Sulfonamides [10] are also used as antibacterial agents. They inhibit cell meta- bolism of bacteria as it mimics p-amino benzoic acid (PABA), one of the normal constitutes of folic acid. The enzyme accepts sulfon- amide into its active site as the structure of sulfonamide is similar to PABA. Once it is bound, the sulfonamide prevents PABA from binding. In our study we have synthesized quinolone compounds, substituted with hydrazine group and-1-oxo-2-hydrazino-3-(p- toluenesulfon) group at 3 position and want to see the results of these molecules as antibacterial. The combination therapy of sul- fonamide and quinolone (7aee) is new approach for the treatment of bacterial infections. 2. Results & discussion 2.1. Chemistry We have already prepared the des-ethyl quinolone derivatives, substituted with carbohydrazide and sulfonyl groups at C-3, but these compounds did not give satisfactory results [11]. Therefore we have synthesized the quinolones (6aee) and (7aee) with N-1-ethyl * Corresponding author. Tel.: þ91 9415157863. E-mail addresses: drnimjpru@rediffmail.com, niveditacdri2000@yahoo.com (N. Srivastava). Contents lists available at SciVerse ScienceDirect European Journal of Medicinal Chemistry journal homepage: http://www.elsevier.com/locate/ejmech 0223-5234/$ e see front matter Ó 2013 Elsevier Masson SAS. All rights reserved. http://dx.doi.org/10.1016/j.ejmech.2013.06.056 European Journal of Medicinal Chemistry 67 (2013) 464e468