Synthesis and antibacterial studies of teixobactin analogues with non-isostere substitution of enduracididine.

Teixobactin is a structurally and mechanistically novel antimicrobial peptide with potent activities against Gram-positive pathogens. It contains l-allo-enduracididine (End) residue which is not readily accessible. In this report, we have used convergent Ser Ligation as the key step to prepare a series of teixobactin analogues with End being substituted with its non-isostere moieties. Among these analogues, compounds T16, T27 and T29 exhibited the best antimicrobial activities against different Gram-positive bacteria with MICs ranging from 0.25 to 1.0 µM. Structure-activity relationship is also established for further development of more promising teixobactin analogues.