A new series of benzimidazolederivatives ,1,2,3 are reported herein. Their reactions with some nucleophiles gave 4 and 6.The reaction of 3 with sodium azide gave 5and with primary amines gave7a-c. Treatment of 7c with acrylonitrile, cinnamaldehyde, phenylisothiocyanate, gave 8,9and 10. Treatment of 10 with chloroacetic acid and/or malonic acid gave 11 and 12. The benzimidazol-2-thione derivative 2 reacted with acetylacetone to give the dicarbonyl derivative 13 which on hydrazinolysis gave the pyrazole derivative 14. Reaction of 2 with benzalacetophenone derivative, anthranilic acid, sodium nitrite and/or thiourea gave 15,16,17and 18 respectively. The formation of the 2-benzimidazolyl pyrimidine thione derivative 19 was also investigated. Some of the new synthesized derivatives were screened for their antitumor activities and theirmolecular docking and the results were encouraging.