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Chemical Synthesis

Building Block Explorer

Introducing the new Sigma-Aldrich Building Block Explorer

Sigma-Aldrich is building the industry’s most comprehensive source of truly available synthetic building blocks for use in chemical synthesis - all conveniently located within our website.

Designed by Chemists for Chemists

For synthetic and medicinal chemists who need to quickly create novel molecular architectures, the Building Block Explorer provides direct access to hundreds of thousands of reliably available synthetic building block products from selected global suppliers chosen for their consistent delivery and premium quality.

More than just a repository of vendor data, the Building Block Explorer displays only products that are truly available. We take the guesswork out of sourcing unique starting materials so you can focus on building the molecules that will advance your project.


Building Block Explorer
Try the new Building Block Explorer.


Frequently Asked Questions
Learn more about purchasing Aldrich Partner Products.


Country Availability
The Building Block Explorer feature is currently available to US customers only but will be expanded worldwide. Sign up to be notified when Building Block is available in your country.


Visit Chemical Synthesis
View our comprehensive Chemical Synthesis Product Line.

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