Patsnap (Patents) 
Patsnap provides access to over 50 million patents from across the world including USA, Europe, WIPO, China, Korea, Japan and Norway.

SciFindern
Authoritative source for identifying a chemical substance and its related chemical structures, chemical names, regulatory information, and properties, including CAS Registry Numbers®, reaction schemes, step-by-step experimental procedures, detailed conditions, and product yields. 
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