Dale B. Mirth

8-Hydroxyquinolines with the Potential for Long-Term Anticaries Activity: Design, Synthesis, and In Vitro Evaluation

8-Hydroxyquinolyl benzoate and 8-hydroxyquinolyl para-(fluorosulfonyl)benzoate have been synthesized and evaluated in vitro as antimicrobial and antiplaque agents. Both compounds inhibited the growth of cultures of the following genera: Streptococcus, Staphylococcus, Actinomyces, Lactobacillus, Veillonella, and Candida. Minimum inhibitory concentrations ranged from 0.98 to 62 μg/ml. Extracted human teeth pretreated with 1% solutions of either compound and rinsed with distilled water exhibited reduced in vitro plaque formation for 48 hours. These results indicate that the in vitro antiplaque activity of 8-hydroxyquinolines can be enhanced by attaching the appropriate side chain in the 8-position.

Alkylamine Salts and Amides: In Vitro Inhibition of S mutans 6715

Our studies with the salts and amides of alkylamines have shown that the undecylenate salts have significant in vitro activity against S mutans No. 6715, suggesting that these agents are worthy of additional evaluation. The attempt to increase activity by combining undecylenic acid with the alkylamines was not successful; however, better attachment to tooth surfaces and/or retention during washing did occur. Our results suggest that the free amino group of alkylamines and the free acid group of undecylenic acid are required for these two classes of agents to demonstrate antibacterial activity.