ChemSpotlight is a Spotlight metadata importer plugin for Mac OS X 10.4 Tiger, which reads common chemical file formats (MDL .mol, .mdl, .sd, .sdf, Tripos .mol2, Protein Data Bank .pdb, Chemical Markup Language .cml, and XYZ) using the Open Babel chemistry library. It is provided as a Universal Binary for PowerPC and Intel, for optimized performance on both.
iBabel gives access to chemical file conversion, sub-structure and similarity searching, overlays, sorting and manipulation of lists of compounds, also include structure viewing capabilities, using JMOLand JChempaint (Included in application bundle).
wxMacMolPlt is an open-source, cross-platform (Mac OS X, Linux and Windows) gui for preparing, submitting and visualizing input and output for the GAMESS quantum chemistry package. Features include a graphical molecule builder, GAMESS input generation, animation of output and visualization of molecules, normal modes, orbitals and other properties.
Mercury offers a comprehensive range of tools for structure visualisation and the exploration of crystal packing.
(commercial) an interactive Chemistry Lab Simulation
Periodic Table X
(commercial) a versatile chemistry reference tool for your Macintosh that takes the periodic table beyond the simple paper periodic table found in so many textbooks and classrooms
SpotSmart is a perl script to enhance ChemSpotlight with substructure searching.