Groups citation sequence

If two or more kinds of a terms occur in the same name, their order of citation is by descending group number of the Periodic Table and increasing atomic number in the group as illustrated by the sequence in Table I. 

For a sequence of more than four asymmetric carbon atoms, two or more prefixes are used. The sequence of asymmetric carbon atoms is divided so that there is a four-carbon prefix for the carbon atoms closest to the principal function, and so that the other prefixes contain the maximal possible number of asymmetric carbon atoms. In the actual name, the order of citation of the prefixes is to start with the grouping furthest removed from the principal function. The most common examples of compounds requiring this type of compound prefixes are the sugars and glycitols with seven or more carbon atoms, two examples of which are given in the accompanying formulas. 

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