But in this case, this hydroxyl on the fifth carbon will react with the carbon that is number two, because this is the carbon of the carbonyl that will act as the electrophile. And so now, instead of forming a six member ring, instead of forming the pyramids, we're going to form a fewer nose, and this is a five membered ring. Why? Well, because we're going to have bond number one, bond number two, three, four, and bond number five. And that means we're going to have five atoms and five bonds inside our ring. And just like in this particular case, we can attack from the top or from the bottom here.