Federal prosecutors in Brooklyn have charged the founder of a U.S.-based cryptocurrency payments firm with operating what they allege was a sophisticated international money laundering scheme that moved over half a billion dollars on behalf of sanctioned Russian banks and other entities.

Iurii Gugnin, a 38-year-old Russian national living in Manhattan, was arrested and arraigned Monday and ordered held without bail pending trial.

Gugnin faces a 22-count indictment accusing him of wire and bank fraud, violating U.S. sanctions and export controls, money laundering, and failing to implement legally required…