What is the business center of london? The west end Buckingham

The business center of London means that there are many working places, many companies there.

The west end of London is entertainment district and the shopping part. 

Buckingham Palace is the London residence and administrative headquarters of the monarch of the United Kingdom. Located in the City of Westminster.

The City is the oldest part of London. There are a lot of banks and  offices.

The Tower of London was a fortress, a palace, a prison and the Kings Zoo.

The East End used to be a purely working district where working-class families lived.