A little while back I wrote a detailed tutorial for getting a wide variety of cheminformatics tools running on a Mac.

Someone just let me know about an issue with OSRA a utility designed to convert graphical representations of chemical structures, as they appear in journal articles, patent documents, textbooks, trade magazines etc., into SMILES

It turns out that OSRA requires ghostscript to process pdf images, this can be installed using brew.

brew install ghostscript