Dear Ibrahim M. Moustafa.
I suppose you already received answers to your question,
but here is my version:
The simplest way of drawing the mirror image of a molecule
is by using a mirror - or looking at the drawing from the other
side, if you have it drawn on (semi)transparent paper.
That should also highlight the fact that axial/equatorial
does not vary among mirror forms.
Now, you may not like the orientation you get from the simple
mirror image. In that case you may need some imagination to
draw the molecule in a different perspective.
But bear in mind that axial stays axial etc.
Sincerely,
/Leif Norskov
Novo Nordisk A/S
Copenhagen
Denmark
LNL^at^novo.dk
> Date: Tue, 12 Aug 2003 17:00:56 +0100
> To: chemistry^at^ccl.net
> From: "Ibrahim M.Moustafa" <im17^at^st-andrews.ac.uk>
> Subject: CCL:Arabinose structure
>
> Dear CCL users,
>
> I have a small question about the stereochemistry representations of
> the pyranoside structure of Arabinose.
> How to draw the chair conformation of the D- and L-forms of Arabinose?.
>
> I'm a bit confused; if I want to draw the pyranoside chair conformation
> (4C1) of the D-form from the Fischer projection in which the
> OH at C2 lies to the left, C3(OH) to the right and C4(OH) to the right,
> I'd draw this chair conformation with:
>
> OH(ax) above the ring at C2, OH(ax) below the ring at C3, and OH(eq)
> below the ring at C4.
>
> Now, If I want to draw the same conformation for the L-form
> (the mirror image of D-form), do I need to alternate the OH groups
> from axial to equatorial and vice versa?
> or how to draw the chair conformation for the L-form?
>
> Appreciated your help.
>
> regards,
> Ibrahim