A total of 62 kinds of compounds to be derived from lichen components by decomposition were synthesized. These included 25 kinds of orcilaldehyde derivatives, 8 kinds of β-orcilaladehyde derivatives, 7 kinds of atranol derivatives, and 22 kinds of divaraldehyde derivatives. Antibacterial action of these compounds were tested with human type tubercle bacilli, the sensitive H37RvS strain and the resistat H37RvR strain which is resistant to over 300 μg/ml of streptomycin, 50 μg/ml of p-aminosalicylic acid, and 50 μg/ml of INAH. None of the compounds tested had antibacterial action against these two strains.
