Why does formation of OSAZONE stops further reaction?

The formation of osazone occurs when a sugar reacts with phenylhydrazine, resulting in the creation of a stable, yellow or orange compound. This reaction effectively blocks further oxidation or reduction of the sugar because the newly formed osazone is a more stable and less reactive product compared to the original sugar. Additionally, the structure of osazones prevents further interactions with reagents that would normally act on the free carbonyl groups of sugars, thus stopping further reactions.