RESIDUE 1Y4 26 CONECT N19 3 C20 C28 H2 CONECT C20 4 N19 C21 H23 H24 CONECT C21 4 C20 C23 N26 H25 CONECT C23 4 C21 C24 H26 H27 CONECT C24 4 C23 C25 H28 H29 CONECT C25 4 C24 N26 H30 H31 CONECT N26 3 C21 C25 C27 CONECT C27 4 N26 C28 H33 H34 CONECT C28 4 N19 C27 C30 H35 CONECT C30 3 C28 O31 OXT CONECT O31 1 C30 CONECT H23 1 C20 CONECT H24 1 C20 CONECT H25 1 C21 CONECT H26 1 C23 CONECT H27 1 C23 CONECT H28 1 C24 CONECT H29 1 C24 CONECT H30 1 C25 CONECT H31 1 C25 CONECT H33 1 C27 CONECT H34 1 C27 CONECT H35 1 C28 CONECT OXT 2 C30 HXT CONECT HXT 1 OXT CONECT H2 1 N19 END HET 1Y4 26 HETNAM 1Y4 (3S,8aR)-octahydropyrrolo[1,2-a]pyrazine-3-carboxylic a HETNAM 2 1Y4 cid FORMUL 1Y4 C8 H14 N2 O2