Website to Draw a Molecule and Receive the Name/CAS Number
Several online tools and software solutions enable users to draw chemical structures and obtain corresponding molecular names and CAS numbers. While no single free website perfectly combines all these features with guaranteed accuracy, a range of options exists to meet these needs.
1. ChemDraw and ChemDraw Direct JS Demo
ChemDraw is a widely used chemical drawing software capable of generating IUPAC names from structures. However, its ability to provide CAS numbers is uncertain and not fully reliable. The software is not free and requires installation. Users can try ChemDraw Direct JS Demo, a free online JavaScript-based tool that offers molecular drawing with name generation, though CAS retrieval is limited.
2. MarvinJS / Marvin Sketch
MarvinJS is a free, web-based chemical editor available at marvinjs-demo.chemaxon.com. It allows users to draw molecules and automatically generate names. It supports basic structure visualization and naming. Additionally, Marvin Sketch, a downloadable free tool, offers similar functionalities and works well on multiple platforms.
3. ChemSpider and PubChem
For name and CAS number retrieval, databases like ChemSpider and PubChem are valuable. Both platforms allow structure-based searches where users can draw or upload a molecule to find its common name, IUPAC name, and CAS number if available. These services are free and widely used by chemists.
4. Sigma-Aldrich Structure-Based Search
Sigma-Aldrich’s online platform provides a structure-based search that can identify chemical names, common names, and information on uses or publications. It is a good resource for commercially relevant molecules, though it may not cover very new or obscure compounds.
5. CACTUS Chemical Identifier Resolver
CACTUS is a chemical identifier resolver that can convert drawn structures to IUPAC names and CAS registry numbers. It supports a variety of input/output formats and offers extensive conversion tools. This free resource is robust for both research and educational purposes.
Additional Tools
- OrganicChemMaster.com allows entering IUPAC names to visualize structures, useful for reverse lookup.
- ChemGenius Molecular Editor (https://chemgenius.pythonanywhere.com) offers molecule drawing capabilities but limited naming support.
- SciFinder is a premium chemical database widely used by professionals for comprehensive chemical information, including CAS numbers.
Summary of Options
| Tool | Draw Molecule | Generate Name | Get CAS Number | Cost |
|---|---|---|---|---|
| ChemDraw (Desktop) | Yes | Yes (IUPAC) | Limited reliability | Paid |
| ChemDraw Direct JS | Yes | Yes | Limited | Free |
| MarvinJS/Marvin Sketch | Yes | Yes | No direct CAS | Free |
| ChemSpider | Yes (search) | Yes | Yes (if known) | Free |
| PubChem | Yes (search) | Yes | Yes | Free |
| CACTUS Resolver | Yes (upload) | Yes | Yes | Free |
| Sigma-Aldrich | Yes (search) | Yes | Yes | Free |
Key Takeaways
- ChemDraw is powerful for naming but less precise for CAS, and costly.
- MarvinJS offers free molecule drawing and naming online without CAS data.
- ChemSpider and PubChem stand out for free structure-based CAS and name lookup.
- CACTUS Chemical Identifier Resolver performs conversions between names, structures, and CAS.
- Sigma-Aldrich provides names and CAS with related chemical info for many molecules.
Leave a Comment