Forty-one kinds of 1-(2-pyridyl)-3-alkyl (or aryl)-2-thiourea, 1-(4-antipyrinyl)-3-alkyl (or aryl)-2-thiourea, and 1-(2-benzothiazolyl)-3-alkyl (or aryl)-2-thiourea were systematically synthesized and their antibacterial action against human type tubercle bacilli H37Rv strain was comparatively examined using the Kirchner medium added with 10% serum or Tween-albumin medium. 1-(2-Benzothiazolyl)-3-butyl-2-thiourea, 1-(2-benzothiazolyl)-3-hexyl-2-thiourea, 1-(2-benzothiazolyl)-3-(p-ethoxyphenyl)-2-thiourea, and 1-(2-benzothiazolyl)-3-(p-tolyl)-2-thiourea showed antibacterial activity comparable to Isoxyl (1, 3-bis (p-isoamyloxyphenyl)-2-thiourea) and Thioban (4-(2-pyridyl)-4'-isobutoxythiocarbanilide) used as the control.
