1 MPO 3[N-morpholino]propane sulfonic acid 1.000 2 6BX (2s)-2-hydroxy-3-(morpholin-4-yl)propane-1-sulfonic acid 0.929 3 6BY (2r)-2-hydroxy-3-(morpholin-4-yl)propane-1-sulfonic acid 0.929 4 1PS 3-pyridinium-1-ylpropane-1-sulfonate 0.857 5 KH2 3-(1-methylpiperidinium-1-yl)propane-1-sulfonate 0.800 6 41D 3-[2-(2-hydroxyethyl)pyridinium-1-yl]propane-1-sulfonate 0.706 7 EP1 3-[4-(2-hydroxyethyl)piperazin-1-yl]propane-1-sulfonic acid 0.706