Structure based on 2kda

Ideal structure
Name: (6r)-3-(2-deoxy-5-o-phosphono-beta-d-erythro-pentofuranosyl)-6-hydroxy-5,6,7,8-tetrahydropyrimido[1,2-a]purin-10(3h)-one
Formula: C13 H18 N5 O8 P
Weight: 403.284
SMILES: "O[CH]1CCN2C(=O)c3ncn([CH]4C[CH](O)[CH](CO[P](O)(O)=O)O4)c3N=C2N1"
Spacial conformation based on PDB 2kda.
Also present on 2lsz
RESIDUE   63H     45
CONECT      O3P    2 P    HO3P
CONECT      C1'    4 C2'  N9   O4'  H1' 
CONECT      C10    4 C11  N2   O10  H10 
CONECT      C11    4 C10  C12  H11  H11A
CONECT      C12    4 C11  N1   H12  H12A
CONECT      C2     3 N1   N2   N3  
CONECT      C2'    4 C1'  C3'  H2'  H2'A
CONECT      C3'    4 C2'  C4'  O3'  H3' 
CONECT      C4     3 C5   N3   N9  
CONECT      C4'    4 C3'  C5'  O4'  H4' 
CONECT      C5     3 C4   C6   N7  
CONECT      C5'    4 C4'  O5'  H5'  H5''
CONECT      C6     3 C5   N1   O6  
CONECT      C8     3 N7   N9   H8  
CONECT      N1     3 C12  C2   C6  
CONECT      N2     3 C10  C2   HN2 
CONECT      N3     2 C2   C4  
CONECT      N7     2 C5   C8  
CONECT      N9     3 C1'  C4   C8  
CONECT      O10    2 C10  HO10
CONECT      O1P    2 P    HO1P
CONECT      O2P    1 P   
CONECT      O3'    2 C3'  HO3'
CONECT      O4'    2 C1'  C4' 
CONECT      O5'    2 C5'  P   
CONECT      O6     1 C6  
CONECT      P      4 O3P  O1P  O2P  O5' 
CONECT      H1'    1 C1' 
CONECT      H10    1 C10 
CONECT      HO10   1 O10 
CONECT      H11    1 C11 
CONECT      H11A   1 C11 
CONECT      H12    1 C12 
CONECT      H12A   1 C12 
CONECT      HN2    1 N2  
CONECT      H2'    1 C2' 
CONECT      H2'A   1 C2' 
CONECT      H3'    1 C3' 
CONECT      H4'    1 C4' 
CONECT      H5'    1 C5' 
CONECT      H5''   1 C5' 
CONECT      H8     1 C8  
CONECT      HO3P   1 O3P 
CONECT      HO1P   1 O1P 
CONECT      HO3'   1 O3' 
END   
HET    63H             45
HETNAM     63H (6R)-3-(2-deoxy-5-O-phosphono-beta-D-erythro-pentofuran
HETNAM   2 63H osyl)-6-hydroxy-5,6,7,8-tetrahydropyrimido[1,2-a]purin-
HETNAM   3 63H 10(3H)-one
FORMUL      63H    C13 H18 N5 O8 P1

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uses Jmol, developed by the Jmol Development Team (color reference)
OCA© by Jaime Prilusky, 1996-2004,2006,2010,2014
Bioinformatics Unit
Weizmann Institute of Science