Antibacterial activity of (−)-deoxypseudophrynaminol versus its racemate and derivatives

(−)-Deoxypseudophrynaminol1 possesses 43-fold greater antibacterial potency than the racemate toward Staphylococcus aureus, indicating that the (−)-enantiomer is the biologically active isomer in this assay. Comparison of the percent growth inhibition by derivatives of 1 indicates that prenylation of N8 and replacement of N1-methyl by methyl carbamate are detrimental to antibacterial potency. (−)-1 is a promising lead structure for the development of the novel hexahydropyrrolo[2,3-b]indole class of antibacterial agents.