Abstract The reaction of sulfamidohydrazonoyl bromide 3 with nucleophiles led to displacement of the bromide. Treatment of 3 with potassium thiocyanate or potassium selenocyanate gave 2-imino-1, 3, 4-thiadiazolines 5 and 2-iminoselenadiazolines 6 respectively. Reaction of 3 with thiourea and phenylthiourea yielded the thiazole derivatives 15 and 16, while dithioesters 26 (or 27) reacts with 3 to afford 2, 3-dihydro-1, 3, 4- ...