ISSN 1070-3632, Russian Journal of General Chemistry, 2016, Vol. 86, No. 1, pp. 154–160. © Pleiades Publishing, Ltd., 2016. 154 Octahedral Titanium(IV) Complexes with Five Novel Hydroximic Acid Ligands: Synthesis, Spectroscopic Characterization, and in vitro Activities on IMR-32 and CHO Cell Lines and Ten Bacterial Strains 1 Sheetal a , K. Nehra b , R. Kaushal c , S. Arora d , D. Kaur d , and R. Kaushal a a Department of Chemistry, National Institute of Technology, Hamirpur, Himachal Pradesh, 177005 India b Department of Biotechnology, Deenbandhu Chhotu Ram University of Science and Technology, Murthal 131039, Sonepat (Haryana), India c Department of Parasitology, PGIMER, Chandigarh 160012 India d Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, 143005 India e-mail: kaushalraj384@gmail.com Received June 25, 2015 Abstract—Complexes with the composition TiCl 4 L 2 where L = benzohydroxamic acid, 2-hydroxybenzo- hydroxamic acid, acetohydroxamic acid, hydroxyurea, and N-hydroxy-N-phenylbenzamide have been synthesized by reaction of titanium tetrachloride with 2 equiv of the corresponding hydroxamic acids. The structure of these complexes has been studied by analytical and spectroscopic (FT-IR, UV-Vis, MS, 1 H and 13 C NMR) techniques. The free ligands and the complexes have been tested in vitro to evaluate their activities against IMR-32 (neuroblastoma) cancer cell line, CHO p-40 (Chinese hamster ovary) normal cells, and ten pathogenic bacterial strains. Keywords: Titanium, hydroxamic acid, spectroscopy, anticancer and antibacterial activity 1 The text was submitted by the authors in English. After the discovery of first hydroxamic acid by Lossen, much attention has been given to biological application of hydroximates due to their ability to inhibit a variety of enzymes, including ureases, peroxidases, and matrix metalloproteinases [1–4]. In medicinal applications, hydroxamic acid moieties are used in the design of therapeutics targeting cardiovascular diseases, insecticides, and antimicrobial agents [5–8]. Hydroxamic acids are usually used as supporting ligands in chemistry and biology because of their tautomerism and potential chelating properties [9, 10]. Generally, tautomers of hydroxamic acid may have different conformations or configurations [11], but they prefer Z-hydroxamic acid structure as shown in Scheme 1. The principal coordination mode observed in metal–hydroxamic acid complexes involves oxygen and nitrogen atoms, and the ligand has either one (hydroxamic) or two hydroxy groups (hydroximic) [12]. In the field of cancer treatment, cisplatin and many other platinum-based drugs, namely carboplatin, oxaliplatin, tetraplatin, and satraplatin [13], as well as non-platinum based drugs such as budotitane, titanocene dichloride [14], NAMI-A, KP1019 [15], and auranofin [16], have shown remarkable results. Among these non-platinum anticancer drugs, budotitane and titanocene dichloride were the first metal-based chemotherapeutics that reached Phase I clinical trials. Although both complexes showed promise in these preliminary studies, budotitane has not progressed past Phase I due to formulation problems, and titanocene dichloride has not progressed beyond Phase II due to its low efficacy versus toxicity ratio [17]. These difficulties have spurred the development of titanium complexes that display higher potency and hydrolytic stability. The structures of some clinically used titanium and ruthenium based anticancer drugs are shown in Scheme 2. In this work we have systematically studied tita- nium(IV) complexes with different hydroxamic acid DOI: 10.1134/S1070363216010242