Partial answer: from St Anatolius: Anatolius of Laodicea and Anatolius of Constantinople. Saints’ names are the default source of given names in Orthodoxy.
The question then becomes, why this saint’s cult was so much stronger in Russia than in Greece—I’ve never heard of a Greek called Anatolios, and the Prosopographisches Lexikon der Palaiologenzeit has only 5 known people of that name in Byzantine texts from the 13th through 15th centuries.