Abstract
Since some of 5-nitro-2-thiophenecarboxylic acid derivatives show strong antibiotic activity, several isoquinoline derivatives which possess 5-nitro-2-thienyl group were synthesized and their pharmacological action was examined. No significant activity was exhibited by any isoquinoline derivative but 5-nitro-2-thiophenecarboxaldehyde, its oxime and ethyl 5-nitro-2-thiophenecarboxylate showed considerably strong anti-syphilis activity. Also, a strong antibiotic effect was seen in two kinds of methyl 5-nitro-2-thiophenecarboxamides. The syntheses of isoquinoline derivatives were carried out by Bischler-Napieralski reaction and a simplified method of Kametani.
