RESIDUE 2R1 20 CONECT N 3 CA H H2 CONECT CA 3 N C CB CONECT C 3 CA O OXT CONECT O 1 C CONECT CB 3 CA CG1 CG2 CONECT CG1 4 CB CD OD1 H48 CONECT CD 4 CG1 OD1 H49 H50 CONECT OD1 2 CG1 CD CONECT CG2 4 CB OD2 H51 H52 CONECT OD2 2 CG2 H53 CONECT H 1 N CONECT H48 1 CG1 CONECT H49 1 CD CONECT H50 1 CD CONECT H51 1 CG2 CONECT H52 1 CG2 CONECT H53 1 OD2 CONECT H2 1 N CONECT OXT 2 C HXT CONECT HXT 1 OXT END HET 2R1 20 HETNAM 2R1 (2E)-2-amino-4-hydroxy-3-[(2R)-oxiran-2-yl]but-2-enoic HETNAM 2 2R1 acid FORMUL 2R1 C6 H9 N O4