0:00
All right.
00:01
So let's talk about the asymmetric carbons in an aldo -tetro.
00:05
So firstly, an aldo -tetro's tetro -4 aldo -aldehyde -based sugar.
00:11
So that's what you're looking at in the farthest left.
00:14
And by asymmetric carbon, they mean chiral centers.
00:18
They mean carbons that have four completely different substituents.
00:22
Guess what? got to one.
00:24
I've got two.
00:26
All right.
00:26
So by stereoisomer, we mean a different r or s absolute configuration at those asymmetrical carbons.
00:34
So the one i've just drawn is it's different at both of them.
00:38
This would actually have its own proper name.
00:40
It would be called in a nanchomer, different at every chiral center.
00:44
But we also could have something called a diastereumer, which means it's only different at one.
00:52
So so far we saw one, two, and now a third stereo isomer.
00:57
But guess what? there's a fourth.
01:00
Well...