2 (H/substituted)-4-aryl-5H,6H, 7-arylimino-1,2,3,5,6-thiatetraazepines (6) have been obtained by basification of 2-(H/substituted)-4-aryl-5H,6H-7-arylmino-1,2,3,5,6-thiatetraazepine monohydrochloride (5).  The latter were synthesized by the interaction of N-aryl-S-chloro isothiocarbamoyl chloride (4) and 1-(H / substituted)-3-aryl-dihydroformazan (3), which were prepared initially by the condensation of aryl acid hydrazide (1) and hydrazine hydrate or substituted hydrazine (2). Compound (6) on benzoylation with benzoyl chloride and excess 10 % sodium hydroxide solution afforded benzoyl derivatives (7) and on boiling with aqueous ethanolic sodium hydroxide solution isomerizes into corresponding 1, 2, 3, 5, 6-pentaazepines (8).  The structures of all the synthesized compounds were established on the basis of elemental analysis, equivalent weight determination, spectral analysis like IR, 1H-NMR and Mass.  These newly synthesized compounds (6) were screened for their antifungal and antibacterial activity.