Such and So-and-so

Such adjective - Having qualities in common.

So-and-so and such are semantically related. In some cases you can use "So-and-so" instead an adjective "Such".

So-and-so noun - A person whose behavior is offensive to others.

Such and so-and-so are semantically related. Sometimes you can use "Such" instead an adjective phrase "So-and-so".