The name of the following of compound is given as propane-1,2,3-triol.


The structure and nomenclature is very simple for this compound (C3H8O3) but my doubt is why propane does not lose the -e in the end, as usual. Like why is it not propan-1,2,3-triol instead? I thought the -e ending is always lost when followed by a suffix (even if there is numbering before suffix) like butan-2-ol. Is it because of the fact that triol starts with a consonant (t) and not a vowel like in most cases of functional group suffix like -ol, -one, -al, -oic acid, etc.