Ascorbyl Glucoside

Ascorbyl glucoside is a water-soluble form of vitamin C that's combined with glucose, a sugar.  In the world of vitamin C and its derivatives, l-ascorbic acid is the most potent, pure version.  Once ascorbyl glucoside is absorbed into the skin, an enzyme called alpha-glucosidas breaks it down into l-ascorbic acid.  This is why you then get all those awesome vitamin C effects such as skin-brightening and wrinkle-smoothing, but, in this case, because it's undergone a conversion process, it's much less likely to cause irritation.