Des vs de

There is this tricky thing in French - des and de with plural.
Almost all the French adjectives go after the noun they denote:
Un livre interessant
So, in plural they are used with plural indefinite 'des':
Des livres interessantes

But! when a noun is used with an adjective that precedes it, like:
Une belle femme
In this case the article for plural changes to 'de':
De belles femmes