Strictly speaking, it depends on how many you're planning on eating. However, I've just looked up tinned prunes in syrup on a supermarket website and they're 26.8g of carbs per 100g. It's a 420g tin, so that's 112.6g for the whole tin. The label also has "intensely sweet" as a tagline, which should probably serve as more of a warning than a selling point.
It's not an option I'd personally consider.