Fig. 1. Design of the AlbD-stable cystobactamid analog 61, with the amide-triazole replacement highlighted in red. The stabilities of 61 (retention time: 13.56 min) and 22 (retention time: 13.56 min) following a 6 h incubation with AlbD have been monitored by LC/UV/MS. Depicted is the UV absorption (190–400 nm) over time. The degradation products (retention times 10.29 min and 12.14 min) are depicted above the chromatograms.