proximately 60% yield, and this substance has been converted to its thiosemicarbazone. Previously, it had been demonstrated that the thiosemicarbazone of 4-(2-thienyl)-3-buten-2- one was capable of completely inhibiting the in vitrc growth of iMycobacterium tuberculosis H37RV in a relatively low c~ ncentration.~ Thus, it was thought to be of interest to prepare the corresponding 3-isomer in order that its activity might be compared with that of the 2- ...