1 PCA Pyroglutamic acid 1.000 2 7YO (2r)-5-oxidanylidenepyrrolidine-2-carboxylic acid 1.000 3 XRE 5-hydroxyproline 1.000 4 2PC 3,4-dihydro-2h-pyrrolium-5-carboxylate 0.889 5 8LJ (2s)-2,3-dihydro-1h-pyrrole-2-carboxylic acid 0.889 6 A1CAB (2s)-3,4-dihydro-2h-pyrrole-2-carboxylic acid 0.889 7 CGN 5-oxo-pyrrolidine-2-carbaldehyde 0.889 8 DPR D-proline 0.889 9 PRO Proline 0.889 10 PYC Pyrrole-2-carboxylate 0.889 11 3BY 1-methyl-L-proline 0.800 12 3WX 2-methyl-L-proline 0.800 13 4FB (4s)-4-fluoro-L-proline 0.800 14 DPL 4-oxoproline 0.800 15 FP9 (4r)-4-fluoro-L-proline 0.800 16 G8X (2~{S},3~{R})-3-oxidanylpyrrolidine-2-carboxylic acid 0.800 17 HY3 3-hydroxyproline 0.800 18 HYP 4-hydroxyproline 0.800 19 HZP (4s)-4-hydroxy-L-proline 0.800 20 JKH 4-amino-proline 0.800 21 MP8 (4r)-4-methyl-L-proline 0.800 22 PXU 2-hydroxy-L-proline 0.800 23 UY7 (4s)-4-hydroxy-D-proline 0.800 24 UYA (4r)-4-hydroxy-D-proline 0.800 25 8GZ D-prolinol 0.778 26 A1IG7 (5~{S})-5-methylpyrrolidin-2-one 0.778 27 PRI Pyrrolidine-2-carbaldehyde 0.778 28 05N (3r,4r)-4-hydroxy-3-methyl-L-proline 0.727 29 53B 6-hydroxypyridine-2-carboxylic acid 0.727 30 6IW (2s,4s)-1-methyl-4-oxidanyl-pyrrolidine-2-carboxylic acid 0.727 31 87I (2r,4r)-1-methyl-4-hydroxyl-pyrrolidine-2-carboxylic acid 0.727 32 A1D9O (2~{S},3~{S},4~{S})-3,4-bis(oxidanyl)pyrrolidine-2-carboxylic acid 0.727 33 A1H05 (2s,3r,4s)-2-[bis(oxidanyl)methyl]pyrrolidine-3,4-diol 0.727 34 EX8 (2~{R},3~{R},4~{S})-3-fluoranyl-4-oxidanyl-pyrrolidine-2-carbaldehyde 0.727 35 FPK 1-formyl-L-proline 0.727 36 H5M Trans-3-hydroxy-5-methylproline 0.727 37 N80 1-ethenyl-L-proline 0.727 38 OA7 6-hydroxypyridine-3-carboxylic acid 0.727 39 OZT (4s,5r)-5-methyl-2-oxo-1,3-oxazolidine-4-carboxylic acid 0.727 40 PBE 1,1-dimethyl-prolinium 0.727 41 PDF 4,4-difluoro-L-proline 0.727 42 PHB P-hydroxybenzoic acid 0.727 43 POM Cis-5-methyl-4-oxoproline 0.727 44 PYB 4-amino-(1-methylpyrrole)-2-carboxylic acid 0.727 45 TJJ 2-oxo-2,3-dihydropyrimidine-4-carboxylic acid 0.727 46 V3C Trans-4-athyl-L-proline 0.727 47 A1A3M (5s)-4,5-dihydro-1h-pyrazole-5-carboxylic acid 0.700 48 C21 Thiophene-2-carboxylic acid 0.700 49 FOA 2-furoic acid 0.700 50 IQ0 Cyclopentanecarboxylic acid 0.700 51 LPD L-prolinamide 0.700 52 PR9 D-prolinamide 0.700 53 PRS Thioproline 0.700 54 T2C (2s)-1,3-thiazolidine-2-carboxylic acid 0.700 55 TFB Tetrahydrofuran-2-carboxylic acid 0.700 56 UJM (2s)-thiolane-2-carboxylic acid 0.700 57 UJP (2r)-thiolane-2-carboxylic acid 0.700