Replacing the 3 hydroxyl groups with chlorine, has turned the raffinose molecule (a sugar molecule) into a chlorinated hydrocarbon molecule or a Organochloride . The transformed molecule is now not a sugar of any chemical description. By definition the addition of the 3 chlorine atoms now ensures that the so called 'Sucralose' molecule (which by its own name is a misnomer, in fact the name 'Sucralose' is in fact a scientifically fraudulent name as it does not conform to any organic chemists idea for a naming convention) is not a sugar, a sugar being a sub grouping of carbohydrate molecules, as carbohydrates by definition only contain carbon, hydrogen and oxygen atoms and most definitely not any chlorine atoms. So by this very fact the so called 'Sucralose' molecule is a chlorinated hydrocarbon molecule and is most definitely not a sugar.

http://www.truthaboutsplenda.com/factvsfiction/index.html

The addition of the chlorine atoms is not a trivial matter, as you are most probably aware even identical molecules which just vary slighty in their structure through mirror image isomerism can be devistating to human growth and health.