Acarbose is an oral alpha-glucosidase inhibitor for use in the management of type 2 diabetes mellitus. Acarbose is an oligosaccharide which is obtained from fermentation processes of a microorganism, Actinoplanes utahensis, and is chemically known as O-4,6-dideoxy-4-[[(1S,4R,5S,6S)-4,5,6-trihydroxy-3-( hydroxymethyl)-2-cyclohexen-1-yl] amino]-a -D-glucopyranosyl-(1->4)-O-a -D-glucopyranosyl-(1->4)-D-glucose. It is a white to off-white powder with a molecular weight of 645.6. Acarbose is soluble in water and has a pKa of 5.1. Its empirical formula is C25H43NO18.