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Benzothiazole derivatives are highly selective and an antitumor therapeutic in vitro and in vivo, highlighting the compound 2-(4'-aminophenyl) benzothiazole (ABT), which exhibits nanomolar concentration activity in vitro against some human breast cancer cells in humans. In this work, we designed new contrast agents based on the structural modification of ABT by complexing them with manganese in order to obtain para-magnetic complexes for efficient diagnosis of breast cancer. The new agents were evaluated by docking studies that allowed investigating interactions and the mode of connection between the active site of the enzyme and the compounds studied. The theoretical and experimental results both indicate that Compound 57 is a promising contrast agent.

Recent attacks on Syria using the nerve agent sarin warned once again the world and the scientists on the use of chemical weapons. It is known that nerve agents are potent inhibitors of acetylcholinesterase (AChE), the enzyme responsible for the hydrolysis of the neurotransmitter acetylcholine and, thus, transmitting of nerve impulses. The process of AChE inhibition by organophosphate (OP) can be reversed by a nucleophile, responsible for dephosphorylation of the residue Ser203 in the active site of the enzyme. In this sense, oximes exhibit this characteristic and are able to remove the neurotoxic and reactivate the enzyme. Here, we review experimental and theoretical results involving docking and quantum mechanical-molecular mechanics hybrid methods (QM/MM), using Molegro® and Spartan® softwares to analyze the interaction of different OPs and oximes with AChE and to evaluate kinetic constants of reactivation.Keywords: Chemical warfare; organophosphates; oximes; docking; QM/MM. ResumoOs ataques recentes na Síria utilizando o agente neurotóxico sarin alertaram mais uma vez a opinião pública mundial e a comunidade científica quanto à utilização de armas químicas. Sabe-se que agentes dos nervos são potentes inibidores da acetilcolinesterase (AChE), enzima responsável pela hidrólise do neurotransmissor acetilcolina e, consequentemente, pela transmissão de impulsos nervosos. A inibição da AChE por um organofosforado (OP) pode ser revertida por um nucleófilo, que desfosforila a Ser203 no sítio ativo da enzima. Nesse sentido, as oximas têm essa característica, pois são capazes de remover o neurotóxico e reativar a enzima. Neste trabalho, revisamos alguns resultados experimentais e teóricos que envolvem estudos de ancoramento molecular e métodos híbrídos quanto-mecânicos/mecânica molecular (QM/MM) usando os softwares Molegro® e Spartan® para analisar as interações de diferentes oximas e OPs com a AChE e avaliar as constantes cinéticas de reativação.Palavras-chave: Guerra química; organofosforados; oximas; ancoramento; QM/MM.