The syntheses of nineteen new X-pantoyl-(substituted-pheny1) alkylamines were accomplished by the condensation of the appropriate amines with pantolactone. Using Lactobacillus arabinosus 17-5 and Leuconoatoc mesenteroides P-60 as the test organisms, all of the derivatives were found to be competitive inhibitors of the utilization of pantothenic acid. For L. mesenteroides, a p-chloro substituent increased the inhibitory activity of the ...