How are compounds in organic chemistry named?
This is more "organic chemistry" question than "biology". And also, anwer to this question needs to be really long because organic chemistry is great part of chemistry and nomenclature is a great part of organic chemistry.
There are many rules on how compounds in organic chemistry are named and those rules are "written" from IUPAC .
Nomenclature is a system of names or terms or the rules for forming these terms in a particular field of arts or sciences.
More about nomenclature you can read here .