Bantamweight McGoldrick got Britain off to the perfect start beating Ivan Ilnytskyy on points however Sam Maxwell, Aston Brown, Babacar Kamara and Uaine Fa all lost thereafter.
That gave Ukraine a 4-1 win, just their second in this season's World Series of Boxing tournament, and sent Britain crashing to the their second defeat from five outings.
McGoldrick used his height and reach advantage well against Ilnytskyy on the way to a split-decision win while double Olympic and world champion Vasyl Lomachenko didn't disappoint on debut against Maxwell.
Drafted in at the weigh-in to replace the ill Dmytro Rudenko, Lomachenko showed his class on the way to the win in lightweight contest however Maxwell left with plenty of positives from the bout.
Southpaw Olexandr Stretskyy and Scot Brown were even early on in their middleweight fight before the Ukrainian edged it and then Oleksandr Gvozdyk dominated Kamara.
Light heavyweight Gvozdyk knocked Kamara down in round one but the Lionhearts fighter fought back and went the distance to lose on points with the defeat securing Ukraine the overall win.
Olympic heavyweight champion Oleksandr Usyk ensured Ukraine ended the evening with a win as he beat Fa with Britain, despite the defeat, still second in the Group B standings at the halfway stage.