Late Stage Functionalization

Starters & Essentials Functionalization Purification Analysis

Starters & Essentials

Sigma-Aldrich offers more than 4000 Biologically Active Small Molecules, available individually or in libraries designed for screening. This includes over 800 Pharma Developed Tool Compounds and Drugs with known activity and toxicity profiles- an ideal starting point for modification through Late Stage Functionalization.


Diversification / Bioconjugation-Ready Pharma Developed Compounds


All Bioactive Small Molecules

Fluorination-Ready Pharma Developed Compounds


All Pharma Developed Compounds

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Select Late Stage Bioconjugation Linkers

Product No. Description
746959 Ethenesulfonyl Fluoride
746118 Sodium difluoroheptylazidosulfinate
792446 Sodium 1,1-difluoro-4-(2-methyl-1,3-dioxolan-2-yl)butane-1-sulfinate
761524 Dibenzocyclooctyne-N-hydroxysuccinimidyl ester
764191 Alkyne-PEG5-N-hydroxysuccinimidyl ester
764523 (E)-Cyclooct-4-enyl 2,5-dioxo-1-pyrrolidinyl carbonate


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Literature & Resources

Pharma Active Compounds
Library of biologically annotated collection of inhibitors, receptor ligands, pharma-developed tools and approved drugs impacting most signaling pathways and covering all major drug target classes.
Goldilocks Chlorinating Reagent
Learn about Palau'chlor®, a safe, easy to handle reagent for the direct introduction of chlorine to heterocycle containing small molecules, in this paper from the Journal of American Chemical Society.
Baran Diversinates
Find the full offering of Baran Diversinates™, able to quickly and easily diversify Bioactive Small Molecules to include a range of chemical functionality, including fluorine.

Sigma-Aldrich provides the building blocks, synthetic reagents and catalysts necessary for the de novo synthesis of Lead compounds and analogs. Subsequent Late Stage Functionalization allows direct access to myriad analogs of similar chemotypic space from one completed synthetic target.


Building Blocks

Featured Fluorination Reagents

Product No. Description
SFL00001 PhenoFluor™
777692 (1,10-Phenanthroline)(trifluoromethyl)copper(I)
719439 XtalFluor-E®
719447 XtalFluor-E®
734039 4-tert-Butyl-2,6-dimethylphenylsulfur trifluoride



Product No. Description
569747 Grubbs Catalyst, 2nd Generation
569755 Hoveyda-Grubbs Catalyst 2nd Generation
577944 Hoveyda-Grubbs Catalyst 1st Generation
579726 Grubbs Catalyst, 1st Generation
771082 [2-(1-Methylethoxy-O)phenylmethyl-C](nitrato-O,O′){rel-(2R,5R,7S)-tricyclo[,7]decane-2,1-diyl[3-(2,4,6-trimethylphenyl)-1-imidazolidinyl-2-ylidene]}ruthenium


Synthetic Reagents

Featured Cross-Coupling Catalysts

Product No. Description
669032 PEPPSI™-IPr catalyst
732117 Pd-PEPPSI™-IPent catalyst
L511706 [(dppf)Ni(cinnamyl)Cl]
L511714 [(dppf)Ni(cinnamyl)]ZnCl3
763403 RuPhos Pd G3
763381 XPhos Pd G3
761605 BrettPhos Pd G3
762830 JackiePhos Pd G3

Literature & Resources

Chemical Synthesis Workflow
The Interactive Chemical Synthesis Workflow - all the tools you need from starters & solvents to reagents and catalysts to affect a de novo synthesis of a Hit or Lead Compound.
Rapid Custom Synthesis
Request a custom product - Sigma-Aldrich's team of synthetic chemists can quickly synthesize your custom starter, intermediate, ligand or catalyst.
Redi-Dri Free Flowing Solids
Learn more about our special packaging that allows for free-flowing, clump-free hygroscopic solids. Put the icepick away, and just pour or scoop!

Solvents destined for use in reactions, product isolation and analysis are highlighted below. A variety of solvent grades are available, segmented by purity and water content, and is tailored to your particular use.


Reaction Solvents: Anhydrous

Reaction Solvents: GC

Reaction Solvents: ACS / Reagent Grade

Selected Reaction Solvents

Product No. Description
401757 Tetrahydrofuran, anhydrous, ≥99.9%, inhibitor-free
296090 Hexane
270997 Dichloromethane, anhydrous, ≥99.8%, contains 50-150 ppm amylene as stabilizer


Literature & Resources

Browse Solvents by Packaging Type
Explore our range of solvents sorted by container: glass bottles; semi-bulk quantities; and the popular returnable container.
Solvents Learning Center
Visit our Solvents Learning Center
Find literature and application guides for all solvent applications: HPLC, NMR, Anhydrous..even green alternatives!