Re: new entries

Alfonso J. Garcia Pineres (
Fri, 10 Feb 1995 16:47:42 -0600 (CST)

Hi All:
I just want to make two observations about the discussion that took place
two weeks ago about chirality
> :) Concerning chirality - 1) I posted E,Z - classification for the sake
> of completeness, and 2) I couldn't possibly explain all the nuances of
> chirality, such as optical inactivity or activity of the diastereomeric
> compounds.
> Artem.

I Think there is a confusion in the use of this term:
Chirality is used only for compounds that are optically active, i mean, if
the compound is optically active, is chiral, and if it doesn't have optical
activity, it's not. The simetry of the molecule is involved, but what makes
a compound chiral is its optical activity.

The E,Z classification of molecules is restricted to Geometric isomers, and
not to stereoisomers, so it is not involved in optical activity.

I think this definition is very useful, but maybe for stereoisomerism, and
not for chirality.

Maybe it's becuase, my english is not good enough, but i wanted to ask
a question :
In the definition, it's written that the fact that the molecules are not
symmetric, allows them to have structures that are not interchangeable. What
i understand from this definition is that setreoisomers are the same
molecule in two different, non interchangeable structures, which, as far as
i know, is not true, stereoisomers are two different molecules.
Again, i think this is a valuable definition, i hope my way of saying my
opinion doesn't offend anybody, this is not my intention.
Alfonso Garcia-Pineres.
Universidad de Costa Rica.