# Question #67d83

Dec 30, 2017

There are three chiral centres in atropine sulfate.

#### Explanation:

I have marked them with asterisks in the diagram below.

Carbon $3$ of the azabicyclo[3.2.1]octane system appears to be chiral. However, it sits on an internal plane of symmetry passing through atoms $3 , 8$, and the mid-point of the $\text{6-7}$ bond, so it is achiral.
Atoms $1$ and $5$ are on opposite sides of this plane, so they are part of a meso system.
It is carbon $2$ of the propionic acid chain that contributes to the optical activity of the compound.