ORIGINAL PAPER The Crystal Structure and Cytotoxicity of Centrosymmetric Copper(II) Complex Derived from S-methyldithiocarbazate with Isatin Mohd Abdul Fatah Abdul Manan • M. Ibrahim M. Tahir • Karen A. Crouse • Rozita Rosli • Fiona N.-F. How • David J. Watkin Received: 11 March 2011 / Accepted: 26 September 2011 / Published online: 11 October 2011 Ó Springer Science+Business Media, LLC 2011 Abstract Copper(II) complex of S-methyldithiocarbazate with isatin has been prepared and screened for their cyto- toxic activities against MCF-7 (Human non-metastatic mammary gland adenocarcinoma cell line) and MDA-MB- 231 (Human metastatic mammary gland adenocarcinoma cell line). The compound crystallized in an orthorhombic crystal system with a space group C 2cb and was found to be selectively active against MCF-7 cell line (Human non- metastatic mammary gland adenocarcinoma cell line with an IC 50 value 0.45 lg/mL. The crystal structure of this centrosymmetric Cu(SMISA) 2 complex (SMISA = Schiff base formed by condensation reaction of S-methyldithioc- arbazate with isatin) showed that the copper atom has a distorted square-planar geometry with the Schiff base coordinated to the metal ion as a uninegatively charged bidentate ligand through the azomethine nitrogen and thiolate sulfur. Keywords Copper(II) Á Centrosymmetric Á Dithiocarbazate Á MCF-7 Á Schiff base Introduction Complexes based on copper have demonstrated various biological activities and appeared to be the most potent antiviral [1], anticancer [2], antimicrobial [3] and anti- inflammatory [4] agents. Anticancer copper (II) complexes appeared to act as either the inducers of apoptosis on human tumor cell lines or agents that alter the cell cycle and decrease the telomerase activity [2]. Isatin (indole-2,3-dione) is a highly conjugated com- pound with an intense orange colour. Its Schiff and Man- nich bases were reported to demonstrate a wide range of biological activities [5–11]. Schiff base of S-meth- yldithiocarbazate with isatin has been reported to behave as a versatile chelating agent exhibiting variable denticity towards metal ions [12]. It has also been reported that copper(II) complexes with isatin Schiff base ligands were potential anticancer agents [13]. Schiff bases derived from S-alkyl/aryl esters of dithio- carbazic acids [14–17] are among the most widely studied sulfur–nitrogen chelating agents. Complexation of these compounds with transition and non-transition metal ions produced stable and intensely coloured metal complexes, some of which have been shown to exhibit interesting physico-chemical and potentially beneficial chemothera- peutic properties [18–20]. Recently, we have reported that Schiff bases derived from S-benzyldithiocarbazate with 5-haloisatins were found to be selectively active towards MCF-7 cancer cell lines [21]. Therefore, as part of our ongoing study on ligands derived from S-alkyl/aryl dithiocarbazates, we M. A. F. A. Manan (&) Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia e-mail: abdfatah@salam.uitm.edu.my M. I. M. Tahir Á K. A. Crouse Á F. N.-F. How Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia R. Rosli Department of Obstetrics & Gynaecology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia D. J. Watkin Chemical Chemistry Research Laboratory, University of Oxford, South Parks Road, OX1 3QA Oxford, UK 123 J Chem Crystallogr (2011) 41:1866–1871 DOI 10.1007/s10870-011-0190-8