Antiviral compounds. XVII - Synthesis and in vitro antiviral activity of 1-substituted 2-chloro- and 2-methoxyindole-3-carboxaldehyde thiosemicarbazones.

A series of indole-3-carboxaldehyde thiosemicarbazones with substituent variations at the 1 and 2 positions were prepared and evaluated for in vitro antiviral activity against vaccinia virus strain IHD and parainfluenza virus type 3, HA-I/CR-8 strain. The inhibitory activity of most compounds was restricted to the vaccinia virus, only compounds (III e) and (III f) being effective against both viruses. Structure-activity relationship are discussed.