diff --git a/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/model/RealTimeExpandingSearchResultModel.java b/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/model/RealTimeExpandingSearchResultModel.java
index d02cafc..22e7d46 100644
--- a/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/model/RealTimeExpandingSearchResultModel.java
+++ b/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/model/RealTimeExpandingSearchResultModel.java
@@ -15,10 +15,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.Executors;
-import java.util.concurrent.ThreadFactory;
-import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.*;
 
 public class RealTimeExpandingSearchResultModel {
 
@@ -58,6 +55,8 @@ private RealTimeExpandingSearchResultModel getThis() {
         return this;
     }
 
+    private final List<Future> expansionTasks = Collections.synchronizedList(new ArrayList<>());
+
     private void processResultsChanged() {
         // we may end up here from edt.. therefore do this
         // async..
@@ -83,6 +82,7 @@ public void run() {
                                     if(moleculeOrder.size()>maxExpandedHits) {return;}
                                     List<String> processed = new ArrayList<>();
                                     for(SynthonAssembler.ExpandedCombinatorialHit xi : exp_hits) {
+                                        if(Thread.interrupted()) {break;}
                                         String processed_idcode = processResultStructure(xi.assembled_idcode);
                                         assembledMolecules.put(processed_idcode,fchi);
                                         processed.add(processed_idcode);
@@ -115,7 +115,10 @@ public void run() {
                             if(getThis().expansionThreadPool==null || getThis().expansionThreadPool.isShutdown() ) {
                                 getThis().restartThreadpool();
                             }
-                            expansionThreadPool.submit(ri);
+                            Future fExp = expansionThreadPool.submit(ri);
+                            synchronized(expansionTasks) {
+                                expansionTasks.add(fExp);
+                            }
                         }
                         //ri.setPriority(Thread.MIN_PRIORITY);
                         //ri.start();
@@ -132,6 +135,17 @@ public void run() {
     private ThreadPoolExecutor expansionThreadPool;
 
     private void initExpansionThreadPool() {
+        if(!expansionTasks.isEmpty()) {
+            List<Future> allTasks = new ArrayList<>();
+            synchronized(expansionTasks) {
+                allTasks = new ArrayList<>(expansionTasks);
+            }
+            for(Future fi : allTasks) {
+                fi.cancel(true);
+                expansionTasks.remove(fi);
+            }
+        }
+
         expansionThreadPool = (ThreadPoolExecutor) Executors.newFixedThreadPool(2);
 
         // Set the lowest priority for each thread
@@ -277,6 +291,13 @@ public Object getValueAt(int rowIndex, int columnIndex) {
     }
 
     public void shutdownThreadpool() {
+        if(!expansionTasks.isEmpty()) {
+            List<Future> allTasks = new ArrayList<>(expansionTasks);
+            for(Future fi : allTasks) {
+                fi.cancel(true);
+                expansionTasks.remove(fi);
+            }
+        }
         this.expansionThreadPool.shutdown();
     }
 
diff --git a/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/view/RealTimeExpandingHitsView.java b/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/view/RealTimeExpandingHitsView.java
index 0c0a801..12043a0 100644
--- a/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/view/RealTimeExpandingHitsView.java
+++ b/openchemlib-hyperspace-core-gui2/src/main/java/com/idorsia/research/chem/hyperspace/gui2/view/RealTimeExpandingHitsView.java
@@ -133,6 +133,7 @@ public void run() {
             });
         }
         this.initMouseContextMenu();
+        SwingUtilities.updateComponentTreeUI(this);
     }
 
     public JPanel getPanelTopRight() {
diff --git a/openchemlib-hyperspace-core/src/main/java/com/idorsia/research/chem/hyperspace/SynthonAssembler.java b/openchemlib-hyperspace-core/src/main/java/com/idorsia/research/chem/hyperspace/SynthonAssembler.java
index 10f7e49..d863a0b 100644
--- a/openchemlib-hyperspace-core/src/main/java/com/idorsia/research/chem/hyperspace/SynthonAssembler.java
+++ b/openchemlib-hyperspace-core/src/main/java/com/idorsia/research/chem/hyperspace/SynthonAssembler.java
@@ -306,6 +306,7 @@ public static List<ExpandedCombinatorialHit> expandCombinatorialHit(SynthonSpace
         current_assemblies.add(new ArrayList<>());
 
         for(int zi=0;zi<frag_sets.size();zi++) {
+            if(Thread.interrupted()) {return new ArrayList<>();}
             List<List<SynthonSpace.FragId>> next_assemblies = new ArrayList<>();
             for( List<SynthonSpace.FragId> ca : current_assemblies) {
                 if(next_assemblies.size()>=max_expanded) {break;}
@@ -324,6 +325,8 @@ public static List<ExpandedCombinatorialHit> expandCombinatorialHit(SynthonSpace
         List<ExpandedCombinatorialHit> results = new ArrayList<>();
         IDCodeParser icp = new IDCodeParser();
         for(List<SynthonSpace.FragId> api : current_assemblies) {
+            if(Thread.interrupted()) {return results;}
+
             List<StereoMolecule> parts     = new ArrayList<>();
             List<String>         parts_ids = new ArrayList<>();
             for( SynthonSpace.FragId fid : api ) {
diff --git a/pom.xml b/pom.xml
index 285975e..c29338e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -32,7 +32,7 @@
         <!--<maven.compiler.target>1.8</maven.compiler.target>-->
         <!--<maven.compiler.release>8</maven.compiler.release>-->
         <!--<maven.compiler.release>8</maven.compiler.release>-->
-        <revision>2.1.28-SNAPSHOT</revision>
+        <revision>2.1.35-SNAPSHOT</revision>
         <!--<maven.compiler.source>${java.version}</maven.compiler.source>-->
         <!--<maven.compiler.target>${java.version}</maven.compiler.target>-->
     </properties>