IUPAC NOMENCLATURE OF ORGANIC COMPOUNDS
IUPAC NOMENCLATURE PROPOSED 1957 ,1993, 2004
Following Rules are used to write the IUPAC names of Organic Compounds :-
Rule-1 SELECT PARRENT CHAIN
            Parrent chain is a longest carbon chain
1. The chain should containing the principal funtional group, substituents ( branch, other funtional group, and multiple bonds as many possible)

2. If two carbon containing funtional group is present on chain we select both funtional group carbon in root name


3. If longest chain has same number of carbons we select which has more branches


4. If more than two similar funtional group are present on carbon chain, All the groups are considering as substituents and give special suffix ( general name)


Ex. COOH =  CARBOXILIC ACID (OIC ACID)
CN = CYANIDE (nitrile)
SEE RULE-2 IN NEXT PART CLICK HERE