Medicinal chemistry Sampaio et al, Med chem 2014, 4:11 http://dx.doi.org/1 0.4172/2161-0444.1000226 Research Article Open Access Med chem ISSN: 2161-0444 Med chem, an open access journal Volume 4(11): 756-762 (2014) - 756 Synthesis, Antiproliferative and Anti-inflammatory Activities of Novel Simplified Imatinib Analogues Thiago Stevanatto Sampaio 1,2 , Lídia Moreira Lima 1,2 *, Renata da Silva Zardo 1,2 , Cláudia Pessoa 3 , Bruno Coêlho Cavalcanti 3 , Rosane de Paula Castro 4 , José Ricardo Sabino 4 , Patrícia Dias Fernandes 1,2 and Eliezer J Barreiro 1,2 * 1 Instituto Nacional de Ciência e Tecnologia de Fármacos e Medicamentos, Laboratório de Avaliação e Síntese de Substâncias Bioativas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, Rio de Janeiro-RJ, Brazil 2 Programa de Pós-Graduação em Farmacologia e Química Medicinal, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, Cidade Universi- tária, Rio de Janeiro-RJ, Brazil 3 Laboratório Nacional de Oncologia Experimental, Departamento de Fisiologia e Farmacologia, Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza-CE, Brazil 4 Instituto de Física, Universidade Federal de Goiás, Goiânia-GO, Brazil *Corresponding authors: LM Lima, Laboratório de Avaliação e Síntese de Substâncias Bioativas, Universidade Federal do Rio de Janeiro, P.O. Box 68024, Zip code: 21944-971, Rio de Janeiro, RJ, Brazil, Tel.+55(21)39386503; E-mail: lidia@lassbio.icb.ufrj.br EJ Barreiro, Laboratório de Avaliação e Síntese de Substâncias Bioativas, Universidade Federal do Rio de Janeiro, P.O. Box 68024, Zip code: 21944-971. Rio de Janeiro, RJ, Brazil, Tel.: +55(21)39386644; Fax: +55(21)39386478; E-mail: ejbarreiro@ccsdecania.ufrj.br Received November 05, 2014; Accepted November 21, 2014; Published November 23, 2014 Citation: Sampaio TS, Lima LM, da Silva Zardo R, Pessoa C, Cavalcanti BC, et al. (2014) Synthesis, Antiproliferative and Anti-inlammatory Activities of Novel Simpliied Imatinib Analogues. Med chem 4: 756-762. doi:10.4172/2161- 0444.1000226 Copyright: © 2014 Sampaio TS, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Keywords: Anti-inlammatory, Antiproliferative, Carboxamide, Imatinib analogues, TNF-α inhibitor Introduction Imatinib, the irst tyrosine-kinase inhibitor to be approved for the treatment of cancer, mainly chronic myelogenous leukemia (CML) and gastrointestinal stromal tumors (GISTs) [1], is considered a milestone in small-molecule drug discovery and molecular targeted therapies. However, unlike the previous report, imatinib is not a speciic inhibitor of ABL, but also inhibits PDGFRs, KIT, ARG (abl-related gene) and potentially other enzymes, which have not yet been tested [2]. Besides its antineoplastic efects, anti-inlammatory and anti- ibrotic activity has recently been assign to imatinib, revealing its multitarget proile [3-7]. However, its exact anti-inlammatory mechanism of action remains elusive. Nonetheless, its ability to down- regulate the expression of inlammatory cytokines, like TNF-α, IL-6 and IL-1β, has been considered a possible mechanism [4,6]. In this paper we describe the synthesis, antiproliferative and anti-inlammatory activities of novel carboxamide derivatives (2a-c) designed as simpliied imatinib analogues (Figure 1) in order to obtain new anti-inlammatory drug candidates. Results and Discussion he carboxamide derivatives (2a-c) were planned by molecular simpliication [8] in the structure of the prototype imatinib (1), resulting in the elimination of 4-(pyridin-3-yl)pyrimidin-2-amine moiety (Subunit A, Figure 1), followed by the classic ring isosterism and retroisosterism [9] of subunits B and C, respectively (Figure 1). he regioisomers (2a-c) were synthesized in three linear steps depicted in Scheme 1. he synthetic route began with reductive amination step, involving the reaction of 2- or 3- or 4-nitrobenzaldehyde (3a-c) with 1-methylpiperazine in the presence of zinc chloride in methanol and sodium cyanoborohydride to obtain the nitrobenzyl- N-methyl-piperazines 4a-c in moderate yield [10]. Interconversion of functional group was carried out based on the reduction of nitro group in respective amine derivatives (5a-c), using metallic iron in the presence of slightly acid solution of ammonium chloride in water and ethanol (1:1) [11]. he condensation of the amines 5a-c with 2-quinaxaloyl chloride, at room temperature using dichloromethane as solvent [12], obtained the desired carboxamides 2a-c in good yields (Scheme 1). he regioisomers 2a-c were fully characterized by 1 H NMR, 13 C NMR and IR spectroscopy and their purity was determined by elementar analysis or HPLC. he possible conformation diferences, arising from the isomerism in the benzyl-N-methylpiperazine unit, were assigned based on the X-ray crystallographic studies performed with carboxamides 2a-c (Figure 2 and Table 1). Abstract We described the synthesis of carboxamide derivatives designed as novel simpliied imatinib analogues and their antiproliferative and anti-inlammatory activities. Compound 2c showed a unique conformation determined by X-ray diffraction and by NMR 1 H and displayed antiproliferative potency in the same magnitude order than the standard imatinib. Compounds 6-10 were prepared by structural modiication in carboxamide 2c, and with exception of derivative 10, they were inactive as antiproliferative agent. However, these compounds showed same anti-inlammatory potency than imatinib, standing out carboxamide 9 that was six time more potent as TNF-α inhibitor production. Figure 1: Design conception of carboxamide derivatives (2a-c) through mo- lecular simpliication from imatinib. N N N N CH3 N H O N N CH 3 H B A 1-benzyl-4-methylpiperazine A = molecular simplification B = ring isosterism C = retroisosterism O N N N CH 3 H N N B C C 1-benzyl-4-methylpiperazine regioisomerism O N H N N O N H N N 2a 2b 2c N N CH 3 N N CH3