Síntese e avaliação biológica de 1,3,4-oxadiazóis derivados da isoniazida

Abstract

Several analogs 1,3,4-oxadiazoles have been reported in the literature due to wide range biological activity, such as: antiviral, antibacterial, antitumoral, antioxidant, anti-inflammatory, anticonvulsivant, antimalarial, antifungal e analgesic activity. With the aim to develop molecules active and selective for some illness, this work describe the synthesis of some N-acyl-hydrazones derivatives and the respective 2,3-dihydro-1,3,4-oxadiazoles, that resulted the obtainment twenty seven inedited derivatives, among them: nine N-acyl-hydrazones derivatives and eighteen 2,3-dihydro-1,3,4-xadiazoles derivatives. At this work were obtainment twenty e eight N-acylhydrazones derivatives through the addition reaction of aromatics and heteroaromatics aldehydes with isoniazid. For the obtainment of N-acyl-hydrazones of long chain, the 4-hydroxybenzaldehyde was alkylated with several alkyl halides: 1-chlorohexane, 1-chlorooctane, 1-bromononane, 1-chlorodecane, 1-chlorododecane, 1-hlorotetradecane and 1-bromopropargyl. It was also proposed the synthesis of two sulfa derivatives, synthesized by the same alkylation methodology with the mesyl and tosyl chloride. These alkylated aldehydes and nineteen commercials aldehydes were condensed to the isoniazid that gave the N-acyl-hydrazones derivatives, which in turn were cyclized to obtain the 2,3-dihydro-1,3,4-oxadiazoles derivatives in reaction with acetic anhydride. The structures of the compounds were elucidated by in infrared, ¹H NMR, ¹³C NMR, 2D NMR techniques, mass spectrometry. The oxadiazoles analogs were submitted to citotoxicity, antibacterial, antioxidant and antimalarial activity. The compounds showed great activity against tumor cells, with selectivity index higher than standard compound used.