Yes, Russia is (still?) a signatory to the European Convention on Human Rights, in which it agrees to be bound by decisions of ECHR. There have been quite a few ECHR cases where monetary compensation was awarded from Russia to someone, and up until now Russia has been complying with these decisions and paying these compensation amounts.
Russia in the process of amending the constitution right now to, among other things, specifically declare priority of Russian law over any decision of international courts.
This is not correct. The amendment text is about priority of Constitution, not all laws. So that mostly means no same sex marriage for Russian citizens.
