diff --git a/core/indigo-core/molecule/canonical_smiles_saver.h b/core/indigo-core/molecule/canonical_smiles_saver.h
index d8e7326363..9ecd63ad8f 100644
--- a/core/indigo-core/molecule/canonical_smiles_saver.h
+++ b/core/indigo-core/molecule/canonical_smiles_saver.h
@@ -19,6 +19,8 @@
 #ifndef __canonical_smiles_saver__
 #define __canonical_smiles_saver__
 
+#include <map>
+
 #include "base_cpp/exception.h"
 #include "molecule/smiles_saver.h"
 
@@ -38,7 +40,7 @@ namespace indigo
         DECL_ERROR;
 
     protected:
-        typedef RedBlackMap<int, int> MapIntInt;
+        typedef std::map<int, int> MapIntInt;
 
         TL_CP_DECL(Array<int>, _actual_atom_atom_mapping);
         TL_CP_DECL(MapIntInt, _initial_to_actual);
diff --git a/core/indigo-core/molecule/src/canonical_smiles_saver.cpp b/core/indigo-core/molecule/src/canonical_smiles_saver.cpp
index 81c521ad66..1ee94c9596 100644
--- a/core/indigo-core/molecule/src/canonical_smiles_saver.cpp
+++ b/core/indigo-core/molecule/src/canonical_smiles_saver.cpp
@@ -37,7 +37,7 @@ CanonicalSmilesSaver::CanonicalSmilesSaver(Output& output) : SmilesSaver(output)
     ignore_hydrogens = true;
     canonize_chiralities = true;
     _initial_to_actual.clear();
-    _initial_to_actual.insert(0, 0);
+    _initial_to_actual.emplace(0, 0);
     _aam_counter = 0;
 }
 
@@ -121,14 +121,15 @@ void CanonicalSmilesSaver::saveMolecule(Molecule& mol_)
         int aam = mol.reaction_atom_mapping[order[i]];
         if (aam)
         {
-            if (!_initial_to_actual.find(aam))
+            const auto it = _initial_to_actual.find(aam);
+            if (it == _initial_to_actual.end())
             {
-                _initial_to_actual.insert(aam, ++_aam_counter);
+                _initial_to_actual.emplace(aam, ++_aam_counter);
                 _actual_atom_atom_mapping[order[i]] = _aam_counter;
             }
             else
             {
-                _actual_atom_atom_mapping[order[i]] = _initial_to_actual.at(aam);
+                _actual_atom_atom_mapping[order[i]] = it->second;
             }
         }
     }