Síntese de derivados benzotiazólicos, benzimidazólicos e clorados de inositol a partir do L-(-)-quebrachitol

Abstract

In this work we describe, in a first moment, the synthesis of inositol derivatives condensed with 2-mercaptobenzothiazole or 2-mercaptobenzimidazole, potential antibacterial agents. In a second part, the preparation of chlorinated inositol derivatives is reported. In the first chapter, we describe the synthesis and antitubercular evaluation of 2-mercaptobenzothiazole and 2-mercaptobenzimidazole derivatives condensed with inositol. These compounds were prepared by opening an epoxide intermediate, which was obtained from L-quebrachitol, a natural product isolated from Hevea brasiliensis. Eight new compounds were synthesized: four 2mercaptobenzothiazole and four 2-mercaptobenzimidazole derivatives. For the preparation of some compounds, microwave irradiation was used as the heating source. A domestic microwave apparatus was adapted for these reactions in our laboratory. Some compounds were evaluated in vitro against Mycobacterium tuberculosis at the laboratory of bacteriology (IPEC) of FioCruz-RJ. However, such compounds did not display biological activity against this microorganism. Some compounds were also submitted for antibacterial activity assay at National Institute of Allergy and Infectious Diseases (NIAID-USA). Chapter 2 of this work reports the preparation of inositols chlorinated at the C2 or C3 position, using as starting material L-quebrachitol. These halogenated derivatives are potential new bioactive compounds, as well as interesting precursors for the preparation of other molecules. The compounds were characterized by infrared spectroscopy, 1H and 13C NMR. Some structures were also characterized by COSY, HMQC, HMBC and mass spectrometry.