Things like Canderel and Splenda are just trade names for the chemical. There are several types, Aspartame, Sorbitol, Acesuflame K to name but a few. Google 'sweeteners' and take your pick.
Most supermarkets make their own sweeteners at a fraction of the cost that are exactly the same. Some are heat stable, some are not.
My personal choice is Tescos red top which is no good for cooking (I think it's Aspartame ) and the yellow top for cooking because it doesn't alter its taste when heated.
There is a wealth of conflicting advice about sweeteners and their safety. You pays your money and takes your choice.
wiflib