Crystal structure and antimycobacterial evaluation of 2-(cyclohexylmethyl)-7-nitro-5-(trifluoromethyl)benzo[d]isothiazol-3(2H)-one

Abstract

The title compound, C15H15F3N2O3S, crystallizes in the monoclinic system, space group I2/a, with Z = 8. As expected, the nine-membered heterobicyclic system is virtually planar and the cyclohexyl group adopts a chair conformation. There is structural evidence for intramolecular N—S...O chalcogen bonding between the benzisothiazolinone S atom and one O atom of the nitro group, approximately aligned along the extension of the covalent N—S bond [N—S...O = 162.7 (1)°]. In the crystal, the molecules form centrosymmetric dimers through C—H...O weak hydrogen bonding between a C—H group of the electron-deficient benzene ring and the benzothiazolinone carbonyl O atom with an R22(10) motif. In contrast to the previously described N-acyl 7-nitro-5-(trifluoromethyl)benzo[d]isothiazol-3(2H)-ones, the title N-cyclohexylmethyl analogue does not inhibit growth of Mycobacterium aurum and Mycobacterium smegmatis in vitro.

Keywords

• benzisothiazolinone
• benzothiazinone
• mycobacteria
• hydrogen bonding
• crystal structure