Structure based on 1k4t

Ideal structure
Name: (s)-10-[(dimethylamino)methyl]-4-ethyl-4,9-dihydroxy-1h-pyrano[3',4':6,7]inolizino[1,2-b]-quinoline-3,14(4h,12h)-dione
Formula: C23 H23 N3 O5
Weight: 421.446
SMILES: "CC[C]1(O)C(=O)OCC2=C1C=C3N(Cc4cc5c(CN(C)C)c(O)ccc5nc34)C2=O"
Spacial conformation based on PDB 1k4t.
Also present on 1rr8, 1rrj
RESIDUE   TTC     54
CONECT      C25    4 C31  C21  H251 H252
CONECT      C31    4 C25  H311 H312 H313
CONECT      C21    4 C25  O24  C16  C20 
CONECT      O24    2 C21  H241
CONECT      C16    3 C21  C15  C17 
CONECT      C20    3 C21  O23  O22 
CONECT      C15    3 C16  C14  C19 
CONECT      C17    3 C16  C13  H171
CONECT      O23    1 C20 
CONECT      O22    2 C20  C19 
CONECT      C14    3 C15  O18  N12 
CONECT      C19    4 C15  O22  H191 H192
CONECT      C13    3 C17  N12  C9  
CONECT      O18    1 C14 
CONECT      N12    3 C14  C13  C11 
CONECT      C9     3 C13  C8   N10 
CONECT      C11    4 N12  C8   H111 H112
CONECT      C8     3 C9   C11  C7  
CONECT      N10    2 C9   C5  
CONECT      C7     3 C8   C6   H71 
CONECT      C5     3 N10  C6   C4  
CONECT      C6     3 C7   C5   C1  
CONECT      C4     3 C5   C3   H41 
CONECT      C1     3 C6   C2   C27 
CONECT      C3     3 C4   C2   H31 
CONECT      C2     3 C1   C3   O26 
CONECT      C27    4 C1   N28  H271 H272
CONECT      N28    3 C27  C29  C30 
CONECT      C29    4 N28  H291 H292 H293
CONECT      C30    4 N28  H301 H302 H303
CONECT      O26    2 C2   H261
CONECT      H251   1 C25 
CONECT      H252   1 C25 
CONECT      H311   1 C31 
CONECT      H312   1 C31 
CONECT      H313   1 C31 
CONECT      H241   1 O24 
CONECT      H171   1 C17 
CONECT      H191   1 C19 
CONECT      H192   1 C19 
CONECT      H111   1 C11 
CONECT      H112   1 C11 
CONECT      H71    1 C7  
CONECT      H41    1 C4  
CONECT      H31    1 C3  
CONECT      H271   1 C27 
CONECT      H272   1 C27 
CONECT      H291   1 C29 
CONECT      H292   1 C29 
CONECT      H293   1 C29 
CONECT      H301   1 C30 
CONECT      H302   1 C30 
CONECT      H303   1 C30 
CONECT      H261   1 O26 
END   
HET    TTC             54
HETSYN     TTC TOPOTECAN, HYCAMTIN
HETNAM     TTC (S)-10-[(DIMETHYLAMINO)METHYL]-4-ETHYL-4,9-DIHYDROXY-1H
HETNAM   2 TTC -PYRANO[3',4':6,7]INOLIZINO[1,2-B]-QUINOLINE-3,14(4H,12
HETNAM   3 TTC H)-DIONE
FORMUL      TTC    C23 H23 N3 O5

This OCA MONOMER page
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