(a) Indicated hydrogen (whether cited in the name or omitted as being conventional).
(b) Principal groups named as suffix.
Examples to Rule C-15.11(a)
(c) Multiple bonds in acyclic compounds (see Rules A-3.1 to A-3.4), in cycloalkanes (see Rule A-11), and in bi-, tri-, and poly-cycloalkanes (see Rules A-31 and A-32), double having priority over triple bonds, and in heterocyclic systems whose names end in -ethine, -oline, or -olene (see Rules B-1.1 and B-1.2).
Examples to Rule C-15.11(b)
(d) Lowest locants for substituents named as prefixes, hydro prefixes, -ene and -yne, all considered together in one series in ascending numerical order.
Examples to Rule C-15.11(c)
(e) Lowest locant for that substituent named as prefix which is cited first in the name (see Subsection C-0.16).
Examples to Rule C-15.11(d)
Note: Hydro and dehydro prefixes, if treated as detachable (see Rule C-16.11), are considered along with prefixes for substituents when this criterion is applied.
Examples to Rule C-15.11(e)
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