Compound is a synonym of Jail. Jail is similar to Prison. Prison is related to Iron. 
Requirement is a type of Mandate. Requirement is related to Essential. Essential is related to Life. Life is related to Creature. 
Compound <--Synonym--> Jail <--SimilarTo--> Prison <--RelatedTo--> Iron 
Mandate <--IsA-- Requirement <--RelatedTo--> Essential <--RelatedTo--> Life <--RelatedTo--> Creature 