Ding, B.; Taotafa, U.; Orsak, T.; Chadwell, M.; Savage, P. B. Org. Lett. 2004, 6, 3433-3436. Synthesis and characterization of peptide-cationic steroid antibiotic conjugates.

New cationic steroid antibiotics have been prepared by conjugating tripeptides to a triamino analogue of cholic acid. These compounds were synthesized on a solid phase in an indexed library that was screened for antibacterial activity against Gram-negative and Gram-positive bacteria. Selected compounds were synthesized on a larger scale, and minimum inhibition concentrations were measured. These results correlated very well with the screening of the indexed library of antibiotics. The most active antibiotics demonstrate a marked improvement over a related and well characterized cationic steroid antibiotic.