765 Available online at www.joac.info ISSN: 2278-1862 Journal of Applicable Chemistry 2013, 2 (4):765-771 (International Peer Reviewed Journal) Synthesis, Characterization and Plant Growth Regulator Activity of Some Substituted 2-Amino Benzothiazole Derivatives Dipesh P. Mahajan, Jitendra D. Bhosale and R. S. Bendre* *School of Chemical Sciences, North Maharashtra University, Jalgaon- 425 001, Maharashtra, INDIA Email: bendrers@rediffmail.com, mahajandp@rediffmail.com Received on 29 th June and finalized on 3 rd July 2013. _____________________________________________________________________________ ABSTRACT Benzothiazole derivatives are the heterocyclic systems that have been found to exhibit diverse biological activities. Therefore, synthesis of benzothiazole derivatives as biologically active substances with various substituents in position 2 was undertaken. The title compounds were synthesized by facile synthetic procedure, starting with substituted aniline and potassium thiocyanate to give substituted 2-amino benzothiazoles, further addition of acid chlorides of substituted phenoxyacetic acid in basic condition was carried out to give the title compounds. All synthesized derivatives were characterized for structural confirmation by IR, 1 H NMR and Mass spectroscopy. The prepared compounds are screened for their plant growth regulator activity. Keywords: Benzothiazole, phenoxyacetic acid, plant growth regulator. ______________________________________________________________________________ INTRODUCTION Benzothiazole and its derivatives represent a large group of heterocyclic compounds, some of which have already found application in the medical sphere as medicines (Kashiyama et al.) as well as in agriculture (Pulkrabek et al., Henselova et al.) as herbicides and plant growth regulators [1]. The benzothiazole derivatives act as herbicides [2], plant growth regulators [3, 4, 5, 6], antibacterial [7], anti-inflammatory [8], antifungal [9, 10], anticonvulsant [11], antitumor activity [12] and antiproliferative activity [13]. Nitrogen and sulfur containing ring is involved in several biologically active compounds. For example, Benzthiazuron and Methabenzthiazuron, derivatives of 2-aminobenzothiazole, were utilized as herbicides [2]. Substituted phenoxyacetic acids are biologically active compounds used as auxins in plant tissue culture. Commercially, they are also used as herbicides. Combination of substituted 2-aminobenzothiazole and substituted phenoxyacetic acid is an effective biologically active system that may be acting as proauxin. After application of these proauxin moieties they efficiently diffuse in the plant body, where they undergo metabolism at different rates and releases active parts. The seedling growth (i.e. emergence and elongation) depends on the environmental conditions and responses to phytohormone signaling pathways [14]. In view of this study, we aimed the synthesis of some substituted 2-amino benzothiazole derivatives as plant growth regulators.