I paid $775 in self employment taxes in 12/2021. These were taxes deferred from 2020. Can I deduct this amount on my 2021 return as a business expense?

Some details: on my 2020 return, I was able to defer my self employment taxes.  I paid half if this deferral ($775) in December 2021.  Can I deduct this amount as a business expense on my 2021 return.  Note: I am still self employed.