uninteresting vs soporific

uninteresting is not a noun while soporific is a noun.

Word	Noun	Adjective	Verb	Adverb
uninteresting	No	Yes	No	No
soporific	Yes	Yes	No	No

uninteresting (noun)	soporific (noun)
	a drug that induces sleep

uninteresting (adjective)	soporific (adjective)
arousing no interest or attention or curiosity or excitement	sleep inducing
characteristic or suggestive of an institution especially in being uniform or dull or unimaginative	inducing mental lethargy