% sphingosine


               c(1,12,(0,nonchiral))-[o(1,left)~,h(1,right)~,h(2,up)~,c(2,down)~],
               c(2,12,(0,chiral))-[h(4,left)~,n(1,right)~,c(1,up)~,c(3,down)~],
               c(3,12,(0,chiral))-[h(8,left)~,o(2,right)~,c(2,up)~,c(4,(down,isomeric(down)))~],
               c(4,12,(0,nonchiral))-[h(10,(nil,isomeric(down)))~,c(3,(up,isomeric(up)))~,c(5,trans)~~],
               c(5,12,(0,nonchiral))-[c(6,(right,isomeric(down)))~,h(11,(nil,isomeric(up)))~,c(4,trans)~~],
               c(6,12,(0,nonchiral))-[c(5,(left,isomeric(up)))~,c(7,right)~,h(13,up)~,h(12,down)~],
               c(7,12,(0,nonchiral))-[c(6,left)~,c(8,right)~,h(15,up)~,h(14,down)~],
               c(8,12,(0,nonchiral))-[c(7,left)~,c(9,right)~,h(17,up)~,h(16,down)~],
               c(9,12,(0,nonchiral))-[c(8,left)~,c(10,right)~,h(19,up)~,h(18,down)~],
               c(10,12,(0,nonchiral))-[c(9,left)~,c(11,right)~,h(21,up)~,h(20,down)~],
               c(11,12,(0,nonchiral))-[c(10,left)~,c(12,right)~,h(23,up)~,h(22,down)~],
               c(12,12,(0,nonchiral))-[c(11,left)~,c(13,right)~,h(25,up)~,h(24,down)~],
               c(13,12,(0,nonchiral))-[c(12,left)~,c(14,right)~,h(27,up)~,h(26,down)~],
               c(14,12,(0,nonchiral))-[c(13,left)~,c(15,right)~,h(29,up)~,h(28,down)~],
               c(15,12,(0,nonchiral))-[c(14,left)~,c(16,right)~,h(31,up)~,h(30,down)~],
               c(16,12,(0,nonchiral))-[c(15,left)~,c(17,right)~,h(33,up)~,h(32,down)~],
               c(17,12,(0,nonchiral))-[c(16,left)~,c(18,right)~,h(35,up)~,h(34,down)~],
               c(18,12,(0,nonchiral))-[c(17,left)~,h(36,right)~,h(38,up)~,h(37,down)~],
               h(1,1,(0,nonchiral))-[c(1,left)~],
               h(2,1,(0,nonchiral))-[c(1,down)~],
               h(3,1,(0,nonchiral))-[o(1,nil)~],
               h(4,1,(0,nonchiral))-[c(2,right)~],
               h(5,1,(0,nonchiral))-[n(1,left)~],
               h(6,1,(0,nonchiral))-[n(1,down)~],
               h(7,1,(0,nonchiral))-[n(1,up)~],
               h(8,1,(0,nonchiral))-[c(3,right)~],
               h(9,1,(0,nonchiral))-[o(2,nil)~],
               h(10,1,(0,nonchiral))-[c(4,(nil,isomeric(up)))~],
               h(11,1,(0,nonchiral))-[c(5,(nil,isomeric(down)))~],
               h(12,1,(0,nonchiral))-[c(6,up)~],
               h(13,1,(0,nonchiral))-[c(6,down)~],
               h(14,1,(0,nonchiral))-[c(7,up)~],
               h(15,1,(0,nonchiral))-[c(7,down)~],
               h(16,1,(0,nonchiral))-[c(8,up)~],
               h(17,1,(0,nonchiral))-[c(8,down)~],
               h(18,1,(0,nonchiral))-[c(9,up)~],
               h(19,1,(0,nonchiral))-[c(9,down)~],
               h(20,1,(0,nonchiral))-[c(10,up)~],
               h(21,1,(0,nonchiral))-[c(10,down)~],
               h(22,1,(0,nonchiral))-[c(11,up)~],
               h(23,1,(0,nonchiral))-[c(11,down)~],
               h(24,1,(0,nonchiral))-[c(12,up)~],
               h(25,1,(0,nonchiral))-[c(12,down)~],
               h(26,1,(0,nonchiral))-[c(13,up)~],
               h(27,1,(0,nonchiral))-[c(13,down)~],
               h(28,1,(0,nonchiral))-[c(14,up)~],
               h(29,1,(0,nonchiral))-[c(14,down)~],
               h(30,1,(0,nonchiral))-[c(15,up)~],
               h(31,1,(0,nonchiral))-[c(15,down)~],
               h(32,1,(0,nonchiral))-[c(16,up)~],
               h(33,1,(0,nonchiral))-[c(16,down)~],
               h(34,1,(0,nonchiral))-[c(17,up)~],
               h(35,1,(0,nonchiral))-[c(17,down)~],
               h(36,1,(0,nonchiral))-[c(18,left)~],
               h(37,1,(0,nonchiral))-[c(18,up)~],
               h(38,1,(0,nonchiral))-[c(18,down)~],
               n(1,14,(1,nonchiral))-[c(2,left)~,h(5,right)~,h(6,up)~,h(7,down)~],
               o(1,16,(0,nonchiral))-[h(3,nil)~,c(1,right)~],
               o(2,16,(0,nonchiral))-[c(3,left)~,h(9,nil)~]