If Syria or Russia, highly unlikely.... But if another country in response attacks Turkey, that would be an article 5 event. The Turks have come to the NATO council in the past, because this has been a long-standing issue with Syria, and they have asked for consultation around this. As you might imagine, at the same time, allies are pretty cautious vis-à-vis the Turks in terms of entangling themselves in something that might lead to an article 5 event.
On February 15th, 2018. See this statement in context.