And what that means is it contains an alkali group on one end, and it contains six carbon atoms, confirmed 12345 and six. So the D glucose will predominate in the cyclic form. And because this is the open chain form, it will have to undergo an intramolecular nucleophilic addition reaction to form the cyclic conformation. And so what happens is the blue hydroxyl group attached to carbon number five attacks this carbon, the electrophile of this aldehyde group. And we form a bond between this oxygen and this carbon. And this bond is shown in purple in this diagram.