Convert TIFF to CDX

Understanding TIFF and CDX file formats

TIFF (Tagged Image File Format) is a widely used raster image format known for its high quality and support for lossless compression. It is commonly used in photography, publishing, and scanning due to its ability to store detailed image data and metadata.

CDX files, in the context of chemistry and molecular design, are proprietary file formats used by ChemDraw software to store chemical structure drawings. CDX files contain vector-based representations of molecules, reactions, and annotations, making them essential for chemists and researchers working with chemical structures.

Why convert TIFF to CDX?

Converting a TIFF image to a CDX file is typically required when you have a scanned or rasterized chemical structure (as a TIFF image) and need to edit or analyze it in ChemDraw. This process involves converting the image into an editable vector format that ChemDraw can interpret.

How to convert TIFF to CDX

Direct conversion from TIFF to CDX is not natively supported by most software, as TIFF is a raster image and CDX is a vector-based chemical structure format. The conversion process generally involves two main steps:

1. Image-to-structure recognition: Use an optical chemical structure recognition tool to interpret the chemical structure from the TIFF image and convert it into a chemical format (such as MOL or directly to CDX).
2. Editing and saving as CDX: Open the recognized structure in ChemDraw and save it as a CDX file.

Recommended software for TIFF to CDX conversion

• ChemScanner: This tool can recognize chemical structures from images (including TIFF) and export them to ChemDraw for further editing.
• OSRA (Optical Structure Recognition Application): An open-source tool that converts images of chemical structures to machine-readable formats (like MOL or SDF), which can then be imported into ChemDraw and saved as CDX.
• ChemDraw: After importing the recognized structure, use File → Save As and select the CDX format.

Step-by-step conversion process

1. Use OSRA to convert the TIFF image to a MOL file:
   osra input.tiff -o output.mol
2. Open the resulting MOL file in ChemDraw:
3. In ChemDraw, go to File → Save As and choose CDX as the output format.

Tips for best results

• Ensure the TIFF image is high quality and clearly shows the chemical structure.
• Manually review and correct the recognized structure in ChemDraw before saving as CDX.
• For batch conversions or complex images, consider professional software like ChemScanner.