Clue: Disreputable business in the East End has groups of schoolkids on drugs (5-9)
Answer: ASSET-STRIPPING
Explanation: Definition: Disreputable business
AS (in the East End, "has", i.e. with the H dropped) + SETS (groups of children in a school) + TRIPPING (on drugs). We quite often see a single answer split into two grid entries, where each entry is a word in its own right, but I don't think I've even seen it done with a long hyphenated word like this.