. Author manuscript; available in PMC: 2015 Nov 24.

Published in final edited form as: Chemistry. 2014 Oct 10;20(48):15824–15832. doi: 10.1002/chem.201403943

Table 3. Stereo-electronic effect of 6-substituted 2-hydroxybenzoic acids.

Signal (ppm)	Contrast(%)	k_ex (s^-1)
9.5	3.4	4800±700
9.0	3.2	4900±600
9.3	0.4	30±10

Conditions: CEST data were obtained at 10 mM concentration, pH 7.3 - 7.4, t_sat = 3 sec, ω₁ = 3.6 μT and 37 °C.