Synthesis and characterization of some newbis-1, 3-oxazepines-4, 7-dione and bis-1, 5-disubstituted tetrazoles linked to benzothiazole and thiadiazole moieties and containing two azo groups

Abstract EN

This work includes synthesis of six bis-1, 3-oxazepines-4, 7-dione [5-7], [9-11] and two bis-1, 5-disubstituted tetrazoles [8] and [12] starting from 5, 5'-(1, 4-phenylenebis(diazene- 1, 2-diyl))bis(2-hydroxybenzaldehyde) [2] and primary amines 5-amino-1, 3, 4-thiadiazole-2-thiol and 2-aminobenzothiazole.

Firstlybis-azoaldehyde derivative [2] was prepared through coupling reaction between P-phenylenediamine [1] and 2-hydroxy benzaldehyde.

The compound [2] was then converted to the corresponding is- imines [3] and [4] viacondensation reaction with each primary amines 5-amino-1, 3, 4-thiadiazole-2-thiol and2-amino benzothiazole, respectively, in presence of glacial acetic acid as catalyst in absolute ethanol.

The bis-imines [3] and [4] were then introduced in [2 + 5] cycloaddition reaction with each maleic anhydride, phthalic anhydride and 3-nitrophthalic anhydride respectively, in dry benzene to give bis-1, 3-oxazepines-4, 7-dione [5-7] and [9-11], respectively.

Treatment ofbis-imines [3] and [4] with sodium azide under [2 + 3] cycloaddition conditions in tetrahydrofuran as solvent resulted the formation of new bis- 1, 5-disubstitutedtetrazoles [8] and [12], respectively.

The structures of the prepared compounds were confirmed by C.H.N.

elementary analysis and the spectroscopic methods including FTIR, 1H NMR and 13C NMRspectra.

These new derivatives probably have some biological activity.