Source code:
@Grab(group='org.openscience.cdk', module='cdk-smiles', version='2.9')
@Grab(group='org.openscience.cdk', module='cdk-silent', version='2.9')
@Grab(group='org.openscience.cdk', module='cdk-depict', version='2.9')
import org.openscience.cdk.smiles.SmilesParser;
import org.openscience.cdk.interfaces.*;
import org.openscience.cdk.silent.SilentChemObjectBuilder;
import org.openscience.cdk.isomorphism.UniversalIsomorphismTester;
import org.openscience.cdk.depict.DepictionGenerator;
uiTester = new UniversalIsomorphismTester();
sp = new SmilesParser(
SilentChemObjectBuilder.getInstance()
)
mol1 = sp.parseSmiles("NCC(=O)OC1=CC=CC=C1C(=O)O")
mol2 = sp.parseSmiles("CCC(=O)OC1=CC=CC=C1C(=O)O")
List<IAtomContainer> list = uiTester.getOverlaps(mol1, mol2);
overlap = list[0]
substructure = mol1.builder.newInstance(IAtomContainer.class)
maplist = uiTester.getSubgraphAtomsMap(mol1, overlap);
for (mapping in maplist) { substructure.addAtom(mol1.getAtom(mapping.id1)) }
new DepictionGenerator()
.withHighlight(substructure.atoms(), java.awt.Color.lightGray)
.depict(mol1)
.writeTo("overlap.svg");
Output: