It's all about the quantities and the delivery mechanism. An apple has about 20g of sugar, about the same as half a can of coke. But two apples come with fiber and vitamins where a can of coke doesn't. That fiber will help you feel full. The coke won't. In fact, the pure refined sugar in a coke will make you feel hungrier.
Also, not all sugars are created equal. Fructose is much worse for you than glucose, so sucrose (which is half glucose and half fructose) is much worse for you than starch, which is long chains of glucose molecules. Also, because your body has to work to decompose starch into glucose, that too will make you feel full longer.
But by far the best thing you can do is replace sugar with non-saturated fat. Fat is not the enemy, sugar -- and fructose in particular -- is the enemy.
Also, not all sugars are created equal. Fructose is much worse for you than glucose, so sucrose (which is half glucose and half fructose) is much worse for you than starch, which is long chains of glucose molecules. Also, because your body has to work to decompose starch into glucose, that too will make you feel full longer.
But by far the best thing you can do is replace sugar with non-saturated fat. Fat is not the enemy, sugar -- and fructose in particular -- is the enemy.