When the power of Congress to exercise its quasi-war powers conflicts with the 5th Amendment takings clause right, and you are an "enemy" in a technical legal sense of the United States as determined by Congress. War powers prevail over the 5th Amendment takings clause.
It is quite analogous to the fact that civil forfeiture of assets used in crimes comes within the police power exception to the 5th Amendment's takings clause.
Essentially, the sanctions are acts under the nation's national security and war powers, comparable in a lot of way to letters of marque and reprisal (which authorize private parties to engage in piracy against an enemy of the United States with compensation drawn from the loot recovered), which are expressly constitutionally authorized, and as regulations of international commerce, rather than being punishments for crimes or torts.
Another comparison would be that the laws of war and the U.S. Constitution do not prohibit U.S. military commanders in the chain of command from the President as Commander-in-Chief from directing that military attacks be directed at particular individuals associated with the enemy and its ability to prosecute the conflict, as opposed to mere innocent civilians immaterial to the enemy's war effort, in order to defeat them in a conflict.
President Biden can, for example, be authorized by Congress to direct his generals to make a foreign leader and all of his cabinet members and generals high priority military targets for the military use of force including deadly force, without individualized due process for those targets.
Essentially, the sanctions represent a legal determination by Congress and the President acting with their military and diplomatic hats on that the individuals sanctioned are alter egos or instrumentalities of the state so deeply tied to the state which are in conflict with (i.e. Russia and Belorussia) that sanctions on them are sanctions on the state with which they are so deeply entwined, rather than being based upon their own personal wrongdoing. In other words, it is basically a Congressionally authorized declaration of war against these individuals by the United States declaring them to be our military enemies, but creating rules of engagement that limit the U.S. to mere economic and immigration oriented means.
While Congressionally authorized sanctions are not done pursuant to a declaration of war against Russia and Belorussia, it is well established that Congress may, consistent with its power to declare war, authorize hostile acts against an enemy or enemies, short of a complete and unregulated declaration of war, basically on the theory that authorization to take the greater act implies the authority to take a lesser act of the same kind.
Many similar sanctions in the past have been sustained in the face of constitutional challenges.
In contrast, a constitutionally prohibited Bill of Attainder, is a declaration that someone is guilty of a preexisting crime based upon a legislative rather than a judicial determination that they did the things that authorize a criminal punishment for those crimes, despite otherwise being a person who is not an enemy of the United States or affiliated with an enemy of the United States in a war-like sense.