Table 2. Inhibitory Activity of Mercaptoacetic Acid Thioesters against Metallo-β-lactamase L1^a.

inhibitor	Ki (μM)	inhibitor	Ki (μM)
1	0.28 ± 0.07	6	0.17 ± 0.02
2	0.41 ± 0.09	7	0.95 ± 0.09
3	0.28 ± 0.02	8	0.17 ± 0.03
4	0.21 ± 0.02	9	0.19 ± 0.02
5	0.11 ± 0.03	10	0.87 ± 0.09

^aK_i values were determined using cefazolin as substrate and L1 as the enzyme in 50 mM Tris, at 25 °C. The inhibitor concentrations were ranged from 0–2.5 μM.