ANTIBACTERIAL ACTIVITY OF 2 ALKYLAMINES INTEGRATED ON AN INDANE SCAFFOLD - MIMICRY OF A COMPLEMENTARY UNIT ON MAGAININ-2

Based on the antibacterial activity of 9-phenylnonylamine (pC9a) again st Escherichia coli (ATCC29522) and Staphylococcus aureus (ATCC25923), we have further tested the inhibitory ability of the growth of the ba cteria by (+/-)1-(4-aminobutyl)-6-benzylindane (PM2) and (+/-)1-benzyl -6-(4-aminobutyl) indane (PM3), that is, two kinds of 1,6-disubstitute d indanes. In an in vitro assay, they showed almost the same antibacte rial activities against the bacteria as pC9a, as well as that of magai nin 2 analogs (i.e., the peptides MSI-78 and 87-ISM), except in the ca se of 87-ISM against S. aureus. At the MIC (minimum inhibitory concent ration) values, however, their killing rate of E. coli is actually qui cker than pC9a. This indicates that an indane scaffold, used as a temp late to mimic a part of the a-helical structure of magainin 2, can acc elerate the killing rate. At present, however, it is unknown whether t ither the hydrophobicity or the alpha-helical structure, or both, of t he indane scaffold is involved in accelerating the rate. Moreover, the se two indanes also showed stronger antibacterial activity against two strains of Helicobacter pylori (ATCC43526, ATCC33579) than either pC9 a or magainin 2 related peptides.