Table 1.

In vitro inhibition of selected carbonic anhydrase isoenzymes [75].

Compound	Linker, Stereochemistry or Substitution	Ki (CA-II) [nM]	Ki (CA-IX) [nM]	Selectivity Index [a]
95−1	Mono, C2	133.10 ± 15.35	0.92 ± 0.28	144.2
91a−	Mono, C2, Cl2	29.85 ± 4.46	0.89 ± 0.15	33.5
91b−	Mono, C3, Cl2	8.10 ± 0.86	0.10 ± 0.02	82.7
93a−	C1, rac-	41.09 ± 6.09	0.86 ± 0.12	47.6
93b−	C2, rac-	164.90 ± 19.86	0.86 ± 0.15	191.5
94a−	C2, meso-	74.17 ± 12.67	0.37 ± 0.05	199.9
93c−	C3, rac-	11.36 ± 1.25	0.02 ± 0.003	668.2
94b−	C3, meso-	26.76 ± 2.45	0.60 ± 0.12	44.5
93d−	C4, rac-	10.07 ± 0.61	0.29 ± 0.01	35.2
94c−	C4, meso-	31.57 ± 3.69	0.06 ± 0.01	574.0

[a] Selectivity index is the ratio between K_i (CA-II) and K_i (CA-IX).