Useful links

Reactome Pathway Database https://reactome.org/userguide/pathway-browser 

A free, open-source, curated database of biological pathways (including metabolic pathways) with an interactive pathway browser to visualize reactions and network maps. 

PathBank  https://pathbank.org/ 

A comprehensive pathway database optimized for metabolomics; you can query metabolite names and it highlights matching pathways with detailed diagrams. 

SMPDB (Small Molecule Pathway Database) https://smpdb.ca/

Interactive visual database of small molecule and human metabolic pathways with searchable metabolite content . 

Human Metabolome Database (HMDB)  https://hmdb.ca/

Comprehensive metabolite database with links to pathways and other databases; useful for chemical, clinical and biochemical data. 

KEGG PATHWAY Database   https://www.genome.jp/kegg/pathway.html 

A classic resource of manually drawn pathway maps showing metabolic networks and reactions; searchable by compound name or identifier.