Norepinephrine: optical isomerism?

[Richard Norman]

In article <876473336.17078 at dejanews.com>, lrobinso at hotmail.com says...
>
>Can anyone tell me if they're aware of any research that is being
>or has been done on optical isomerism in norepinephrine?  Like many
>complex biological molecules, norepinephrine has "right-" and
>"left-handed" forms. Are both neuroactive?
>

The Merck Index clearly identifies only the l form as being active.
Also the Sigma catalog is very clear (at least for epinephrine) in
identifying the l form as the one you probably want to buy, even
though they stock both.