α & β lactose

[clubcard]

I note that lactose as 2 forms, a-lactose & β-lactose. I've searched the web for some time and nowhere does it show the chemical difference. Physically β-lactose is (from what I read) much more water-souble and some stippits like it's made via crystallization above 96C BUT I still don't know what they look like. Some people on other boards say they are equally soluble but the 1 text-book I read said it was 2.5x more soluble in water.

I have found the SMILES of the two... but not which one is which.

Could someone please confirm

 

[Tryptamite]

Advanced D Discussion?

 

[tweex]

This is NPD material (funny how we went from Attention Deficit Disorder to Narcissistic Personality Disorder? )

The difference is the orientation of the hydroxyl group on the far right, and Beta lactose is the more soluble of the two.
http://www.enc-conference.org/portals/0/Abstracts2012/ENC20121124.3125VER.1.pdf
http://www.raw-milk-facts.com/lactosefactsT3.html

 

[clubcard]

Does this stuff have a CAS?

 

[tweex]

http://www.commonchemistry.org/ChemicalDetail.aspx?ref=63-42-3

 

[clubcard]

Like this

http://www.chemspider.com/Chemical-Structure.5904.html

?

 

[NeighborhoodThreat]

Basic Drug Discussion --> Neuroscience and Pharmacology Discussion

 

[endotropic]

I'm not sure how much more can be said here. Beta-lactose is more soluble, but the two forms do interconvert to some extent.

Look here if you still don't understand the difference in the structures (also includes CAS#):

http://www.sigmaaldrich.com/catalog/product/sigma/l3625?lang=en&region=US
http://www.sigmaaldrich.com/catalog/product/sigma/l3750?lang=en&region=US

 

[sekio]

This isn't really NPD material. No neuroscience or pharmacology here.

I would expect they're both soluble in water.

 

[clubcard]

Thanks all. The anhydrous β-lactose is supposed to be several times more soluble in water. I don't know why, but I was interested in the large increase in solubility but so far I cannot even find a vendor (I know - I'm not asking, just remarking) to ask what the stuff is used for.