By Laur on Wednesday, January 29, 2003 - 08:22 am:
Hello
I want to develop a chiral HPLC method for separation of some enantiomers of basic compounds (eg. metoprolol, atenolol). I have a Ultron ES-OVM 150x2.1 mm chiral column and I also have an chiral derivatisation compound R(+)naphtylethyiisocianate. For some racemics the Ultron column only can’t resolve very well the enantiomers. The question is: Does anyone know what is the behaveour of diastereoisomers in a chiral column? Is the resolution improved in comparison with single enantiomers?
Thank you
By Anonymous on Wednesday, January 29, 2003 - 11:15 am:
Laur,
I have prepared a couple of diastereomer derivatives like you are proposing. They have both separated well on a normal C-18 LC column, didn't need a chiral column. You might make the derivatives and try an efficient C-18 column first.
Regards,
Mark
By H W Mueller on Thursday, January 30, 2003 - 12:00 am:
See also the chain: "Diastereo Isomers by HPLC" of Jan 10.
By Benjamin on Thursday, January 30, 2003 - 10:37 am:
Laur;
I have done a fair amount of work with Ultron columns.
If you want to try to separate the derivatized molecules you mention using the Ultron column, I would recommend you to be careful. Those derivatives are likely to be much more hydrophobic that the original molecules and therefore highly retained in the Ultron column.
As you know, the column has a limit on how much organic solvent you can use in the mobile phase, and it will be difficult or impossible to elute them.
I agree with the recommendation above, use a non-chiral column to separate the derivatives.
Good Luck;
Benjamin
By laur on Friday, January 31, 2003 - 03:33 am: