In 2017 I paid $6,000 to IRS for CP521/Installment Agreement. Can I deduct these as a tax expense?

[pettilegal]

The CP 521 arose out of nonpayment of my small business payroll withholding taxes, and was a combination of back taxes and high interest rates on the unpaid back taxes that have now been fully paid.

[Phillip1]

No. 

Federal taxes, interest, and penalties are not deductible on your individual income tax return