Perhaps you should try some spelling variations:
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"bridges bicyclic compounds, heterocyclic / economics" » "bridges cyclic compounds, heterocyclic / economics", "bridges macrocyclic compounds, heterocyclic / economics", "bridged bicyclic compounds, heterocyclic / economics", "bridged bicyclo compounds, heterocyclic / economics"
"bridges bicyclo compounds, heterocyclic / economics" » "bridges cyclic compounds, heterocyclic / economics", "bridged bicyclo compounds, heterocyclic / economics", "bridged bicyclic compounds, heterocyclic / economics"

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