If your 4th-quarter estimated tax payment covers the tax on the sale you will be able to avoid an underpayment penalty (provided that you paid enough estimated tax in the first three quarters to cover the tax on income earlier in the year). In order to avoid the penalty you will have to file Form 2210 with your tax return and use the annualized income method (Schedule AI) to take account of the fact that all the additional income was in the fourth quarter. Without that the IRS would assume that the income occurred evenly during the year, meaning that you should have paid more estimated tax earlier in the year.
