Chemical entities can appear in scientific texts as trivial and brand names, assigned catalog names, or IUPAC names. However, the preferred representation of chemical entities is often a two-dimensional depiction of the chemical structure. Depictions can be found as images in nearly all electronic sources of chemical information (e.g. journals, reports, patents, and web interfaces of chemical data bases).
Nowadays these images are generated with special drawing programs, either automatically from connection table file formats or by the chemist through a graphical user interface. Although drawing programs can produce and store the information in a computer-readable format, chemical structure depictions are published as bitmap images (e.g. GIF for web interfaces or BMP for text documents). As a consequence, the structure information can no longer be used as input to chemical analysis software packages. To make published chemical structure information available in a computer-readable format, images representing chemical structures have to be manually converted by redrawing every structure. This is a time-consuming and error-prone process.
Have some fun redrawing it ...