BRIF RESUME ON INTENDED WORK
6.1 Need for The Study: -Intrinsic resistance to antimicrobial agents by microorganisms is recognized from the beginning. The spread of this phenomenon is abetted by short generation time and genetic versatility of microorganisms, as well as by poor antibiotic prescribing and utilization practices. In particular, last decade has witnessed a dramatic increase worldwide in incidence of bacterial strains that are resistant not only to penicillins but also to macrolides, tetracyclins, sulfonamides and other antibacterial agents. Diseases which very recently seemed on their way to extinction, such as tuberculosis and gonorrhea are once again becoming serious public health problems because of societal changes and resistance emergence by pathogens. In India; bacterial infections are highly prevalent because of lack of public hygiene and sanitation. Therefore, the search and development of novel molecules as antimicrobial agents for fast and effective relief from microbial infections in the human beings is a major challenge for the medicinal chemists.
Benzothiazoles are precursors to natural products, pharmaceutical agents and other compounds that exhibit a wide spectrum of biological activity such as antitumour, immunosuppressive, immunomodulatory and antiviral properties.1 Various methods of synthesis of benzothiazoles are known.2 Among these is the Jacobson synthesis—oxidative cyclization of an arylthioamide on an unsubstituted ortho position, using potassium ferricyanide in a basic medium.3 This method has been well used for the preparation of substituted benzothiazoles.4–6
Aminobenzolthiazoles constitute an important class of compounds. Their chemistry and biological potencies have been extensively investigated and reviewed in the past years.7-12
The substituted benzothiazole derivatives have antitumour13, vasodilator14, antitubercular15, antifungal16,CNS17 activities. The 2-(4-aminophenyl) benzothiazoles are novel class of potent and selective antitumour agents and display a characteristic profile of cytotoxicity response across the cell lines.
Thiazole and imidazo[2,1-b]-thiazole derivatives are proven to be safer and better drug molecules that are found to posses diversified biological activities like anti-bacterial, diuretic, antifungal, leismaniacidal, antitubercular, anticancer, anticonvulsant etc. In addition, levamisole, a well known anthelmintic drug contains imidazo[2,1-b]-thiazole moiety and also exhibits profound effect as anti-arthritic and immuno-modulatory activity.18-23
It has been reported that 3’-benzoylurea derivatives of 6-phenyl-2,3,5,6-tetrahydroimidazo[2,1-b]-thiazole,which are similar to tetramisole have anthelmintic activity22.Also compounds containing imidazo[2,1-b]thiazole system are synthesized and found to be closely related to Tetramisole.24
Therefore in the present work we have planned to synthesize the title compounds and evaluating their antimicrobial property with appropriate methodologies.
6.2 Review of Literature:
Extensive literature survey was carried out in Karnataka University Dharwad, libraries of KLE’S College of Pharmacy Hubli and Belgaum and by visiting various web sites through internet the relevant data has been collected.The mentioned advantages and the potency of benzothiazoles and its derivatives prompted to take up the synthesis and biological activities. Further, the literature review helped in identifying the research gap.
Several methods for the synthesis and pharmacological properties of sbstituted benzothiazoles reported in the literature.
Aljarin M. et. al., have reported the synthesis of novel benzothiazoles by cyclisation of ketenimines bearing sulfenylimine fragments.25 Transient ketenimines containing sulfynylimine fragment in which both functionalities are linked by an orthophenylene scaffold through their nitrogen and sulphur atoms respectively
Oren I Y, et. al., have synthesized and studied Structural Activity Relationship of new Antimicrobial active multisubstituted benzothiazole derivatives.26
Ambatti N.B, et. al., have detailed a facile synthetic route for 2-N (Methyl Amino) Benzothiazoles. Titled compounds were synthesized by using primary aromatic amines and methyl isothiocyanante.27
Katz.L, , et. al., have successfully synthesized, characterized and studied antitubercular activity of 2-Benzylhydrazino Benzothiazoles.28
Bhusari.K.P, et al., have reported the synthesis and antitubercular activity of some substituted 2-(4-aminophenylsulphonamido) benzothiazoles.29
L.V.G.Nargund, et al., synthesized 6-Fluoro-7-[aniline/morpholino/piperazino]-2-[N-p-tolyl sulphonamido] benzothiazoles.30
Ganpatrao Barsu Khadse, et al., synthesized substituted phenyl imidazo[2,1-b]benzothiazoles.31
Charles J.R, et al., have reported synthesis and anxiolytic activity of imidazo[2,1-b]-benzothiazoles.32
6.3 Objective of the study:
Ø To synthesize substituted novel diaryl substituted imidazo [2,1b] Benzothiazole derivatives as antimicrobial agents..Ø To characterize the structure of these compounds by using UV, IR, NMR and Mass spectral data.
Ø To screen these newly synthesized compounds for antimicrobial activity
7 /
MATERIALS AND METHODS
7.1 Sources of dataData are obtained from laboratory experimentation techniques including
a) Synthesis of substituted imidazo [2,1b] Benzothiazole derivatives.
b) Spectral studies of these compounds by UV, IR, NMR and Mass spectral data.
c) Biological screening (i.e. data generated from antimicrobial activity.)
7.2 Method of collection of data:
(Including sampling procedure if any)
Necessary data for synthesis and biological evaluation will be collected by literature
survey.
A]Synthetic Studies:
B] Antimicrobial activity:
Antimicrobial activity of newly synthesized compounds will be carriedout by zone of inhibition using cup-plate method.33 Compounds, which will show the better antimicrobial activity by cup-plate method will be further, evaluated for minimum inhibitory concentration (MIC) by serial dilution method.34
7.3 Does the study required any investigation or intervention to the conducted
on patients or humans or animals? If so, please describe briefly.
-- Not applicable.
7.4 Has ethical clearance been obtained from your institution in case of 7.3?
-- Not applicable.
8. /
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