New chemical entity

A new chemical entity is like a brand new toy you've never seen before. It's never been made or used by anyone else before. Scientists who make new chemical entities work in special places called labs. In the labs, they mix different ingredients together to make the new toy or chemical. Just like when you mix paints to get a new color.

These new chemicals are important because they can be used to make new medicines, like ones that help people feel better when they're sick. Scientists have to make sure the new chemical is safe before they use it in medicine, just like a grown-up makes sure a toy is safe before you play with it.

So, just like how you get excited to play with a new toy, scientists get really excited when they make a new chemical entity because it means they have a brand new tool to use for helping people feel better when they're sick.