# Stage 2: acyclic parents and senior functional groups
CCO
CC(C)C
CCCCCCCCCCCCC
CCCCCCCCCCCCCCCCCCCC
O=C=O
OC(=O)O
NC=O
N=C=O
ClC(=O)Cl
FC(=O)F
C=O
CC(=O)Cl
CC(=O)OC
O=C(O)CO

# Stage 3: monocyclic and skeletal replacement parents
C1CCCCC1
C1=CCCCC1
c1ccccc1
c1cc(Cl)ccc1[CH3]
c1ccncc1
Oc1ccccc1
C1COCCN1

# Stage 4: von Baeyer, spiro and ring collections
C1C2CC3CC1CC(C2)C3
CC1CCC2CCC1C2
C1CC2CCC1C2
C1CCC2CCCCC2C1
C1CCC12CCCC2
c1ccc2ccccc2c1
c1ccc(-c2ccccc2)cc1

# Stage 5: senior functional groups on ring systems and mixed acyclic parents
O=C(O)c1ccccc1
CC(=O)Oc1ccccc1
NC(=O)C1CCCCC1
O=C1CCCCC1
CC(=O)CC(=O)O
NC(=O)Cl
O=C(O)N
ClC(=O)O

# Stage 6: explicit stereo, isotope, charge and disconnected components
N[C@@H](C)C(=O)O
C/C=C/C
[13CH4]
[NH4+]
C.C
