Ethylenediamine, also known as 3-O-ethyl ascorbic acid, is a vitamin C derivative that is more stable and more effective at penetrating the skin than traditional vitamin C. It acts as an antioxidant on the skin, helping to neutralize free radicals that contribute to skin aging. It reduces discoloration and improves overall skin tone. It stimulates collagen production, which improves skin elasticity and reduces the appearance of wrinkles. It can provide additional protection against UV damage, but it is not a substitute for SPF. When used in cosmetics, ethylated vitamin C can help smooth and soften the skin.