1 B71 3-(decyloxy)-1-(2,2-diphosphonoethyl)pyridinium 1.000 2 714 1-(2,2-diphosphonoethyl)-3-(octyloxy)pyridinium 0.926 3 722 1-(2,2-diphosphonoethyl)-3-(heptyloxy)pyridinium 0.889 4 721 3-butoxy-1-(2,2-diphosphonoethyl)pyridinium 0.778 5 H86 3-(decyloxy)-5-(3,5-difluorophenyl)-1-(2,2-diphosphonoethyl)pyridinium 0.771