TABLE 1.

Equilibrium solubilities in HBSS* at 37°C and compound mass determined through mass spectrometry of MMTC, 53B, 54F, 55B, and 57B. Solubilities are shown as means ± SD of triplicate determination (N = 3). The exact masses of the compound adducts are shown along with the determined mass.

Compound name	MMTC	53B	54F	55B	57B
Equilibrium solubility, [µM]	<1.8	24.9 ± 0.8	56.1 ± 0.5	13.2 ± 1.6	27.5 ± 1.0
Mass spectrometry adduct	Na+	H+	H+	H+	H+
Exact mass, Da	491.0681	386.1975	411.0501	421.1062	444.1619
Determined mass, Da	491.0701	386.1961	411.0516	421.1076	444.1618