RESIDUE 721 41 CONECT O6 1 P2 CONECT P2 4 O6 O5 O4 C1 CONECT O5 2 P2 HO5 CONECT O4 2 P2 HO4 CONECT C1 4 P2 P1 C2 H1 CONECT P1 4 C1 O3 O2 O1 CONECT O3 1 P1 CONECT O2 2 P1 HO2 CONECT O1 2 P1 HO1 CONECT C2 4 C1 N1 H2 H2A CONECT N1 3 C2 C3 C7 CONECT C3 3 N1 C4 H3 CONECT C4 3 C3 C5 H4 CONECT C5 3 C4 C6 H5 CONECT C7 3 N1 C6 H7 CONECT C6 3 C5 C7 O7 CONECT O7 2 C6 C8 CONECT C8 4 O7 C9 H8 H8A CONECT C9 4 C8 C10 H9 H9A CONECT C10 4 C9 C11 H10 H10A CONECT C11 4 C10 H11 H11A H11B CONECT HO5 1 O5 CONECT HO4 1 O4 CONECT H1 1 C1 CONECT HO2 1 O2 CONECT HO1 1 O1 CONECT H2 1 C2 CONECT H2A 1 C2 CONECT H3 1 C3 CONECT H4 1 C4 CONECT H5 1 C5 CONECT H7 1 C7 CONECT H8 1 C8 CONECT H8A 1 C8 CONECT H9 1 C9 CONECT H9A 1 C9 CONECT H10 1 C10 CONECT H10A 1 C10 CONECT H11 1 C11 CONECT H11A 1 C11 CONECT H11B 1 C11 END HET 721 41 HETNAM 721 3-butoxy-1-(2,2-diphosphonoethyl)pyridinium FORMUL 721 C11 H20 N1 O7 P2 1+