Original article Investigation of anticancer potencies of newly generated Schiff base imidazolylphenylheterocyclic-2-ylmethylenethiazole-2-amines Nikhil M. Parekh a, 1 , Bhupendra M. Mistry b, 1 , Muthuraman Pandurangan b , Surendra K. Shinde c , Rahul V. Patel d, * a Department of Mathematics, Science & Humanities, Shroff S. R. Rotary Institute of Chemical Technology, Valia 393 135, India b Organic Research Laboratory, Department of Bioresources and Food Science, College of Life and Environmental Sciences, Konkuk University, Seoul 143 701, Republic of Korea c College of Life Science and Biotechnology, Department of Biological and Environmental Science, Dongguk University, 32, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-820, Republic of Korea d Department of Food Science and Biotechnology, Dongguk University-Seoul, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-820, Republic of Korea A R T I C L E I N F O Article history: Received 8 June 2016 Received in revised form 23 August 2016 Accepted 8 September 2016 Available online xxx Keywords: Schiff Base Imidazole Thiazole Anticancer Drug designing SAR A B S T R A C T A new series of multi-heterocyclic Schiff base was constructed starting from 4 0 -(imidazol-1-yl)- acetophenone which was converted to its 2-bromoethanone precursor which on cyclic condensation with thiourea yielded final thiazol-2-amine intermediate (3) to be reacted with substituted aldehydes to generate final imidazolylphenylheterocyclic-2-ylmethylenethiazole-2-amines (4a–4i). New Schiff base was investigated for their in vitro cytotoxic efficacies against a panel of three human cancer cell lines namely, MCF7 (human breast cancer), HCT116 (human colon cancer), and DU145 (human prostate cancer) and one normal skin fibroblast (SF). Most of these synthetic derivatives shown important cytotoxic actions against individual carcinoma cell line collections, but weak actions against SF, which is as anticipated. Observations of SAR suggested that the difference in the characteristics of substituents attached to the Schiff base function leads to the interesting variations within pharmacological effects of resultant molecular systems. Structural analysis performed using FT-IR, 1 H NMR, 13 C NMR spectroscopy and CHN analysis for final potent anticancer Schiff base, which warrant further investigations. © 2016 Rahul V. Patel. Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved. 1. Introduction Schiff bases, named after Hugo Schiff and their very first formation was accomplished in the nineteenth millennium [1]. They are known as azomethine or imine as nitrogen analogue an aldehyde or ketone structurally, where imine or azomethine group found to replace the carbonyl group [2]. Schiff base is very widely used and the most appreciated organic building blocks to have a diverse range of pharmacological importance as well as a versatile tool to explore in many other fields as biological, inorganic and analytical chemistry. They hold a spectrum of biological importance as antioxidant, anthelmintic, antitubercular, anti- inflammatory, anticancer, antimicrobial, anticonvulsant and so forth [3]. The active centers of cell constituents are supposed to get interacted with azomethine’s nitrogen atom via forming a hydrogen bond which interferes with normal cell processes [4] and results in the destruction of enzymatic activity of cancerous cells, thereby presents Schiff base as a potential target to discover anticancer chemotherapeutics. Hence, in the current research, we were directed to construct Schiff base derivatives involving the presence of three different types of heterocycles as imidazole, thiazole, and other heteroaromatics. Imidazole ring, highly polar heterocycle, is an important five-membered aromatic heterocycle widely present in natural products and synthetic molecules. It readily binds with different targeted enzymes in a biological system via ion–dipole, coordination, van der Waals forces, p–p stacking, hydrophobic effects, cation–p, and so on, because of its unique electronrich characteristic which establishes diverse weak interactions, thereby exhibiting broad bioactivities [5]. Hence, we have selected imidazole as a starting heterocyclic core to build the desire Schiff bases with intermediate thiazole entity which represents a versatile tool to generate anticancer chemotherapeu- tics [6]. Finally, different N, S and O-based heterocycles were * Corresponding author. E-mail address: rahul.svnit11@gmail.com (R.V. Patel). 1 Authors contributed equally. http://dx.doi.org/10.1016/j.cclet.2016.10.021 1001-8417/ © 2016 Rahul V. Patel. Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved. Chinese Chemical Letters xxx (2016) xxx–xxx G Model CCLET 3856 No. of Pages 5 Please cite this article in press as: N.M. Parekh, et al., Investigation of anticancer potencies of newly generated Schiff base imidazolylphenylheterocyclic-2-ylmethylenethiazole-2-amines, Chin. Chem. Lett. (2016), http://dx.doi.org/10.1016/j.cclet.2016.10.021 Contents lists available at ScienceDirect Chinese Chemical Letters journal homepa ge: www.elsevier.com/locate/cclet