1 BTB 2-[bis-(2-hydroxy-ethyl)-amino]-2-hydroxymethyl-propane-1,3-diol 1.000 2 VLS N-[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl]glycine 0.733 3 211 2,2',2''-nitrilotriethanol 0.714