2-(Tert-butoxycarbonyl)-2-azaspiro[3.5]nonane-7-carboxylic acid

CAS 1363381-18-3

What does spiro[3.5] mean? The numbers count ring atoms apart from the shared spiro atom, giving a four-membered ring and a six-membered ring. CAS 1363381-18-3 combines that framework with a Boc-protected ring nitrogen and a free carboxylic acid. A patent on IRAK degraders explicitly uses the acid as a starting material and transforms its external functionality toward an aminomethyl connection while retaining nitrogen protection. This illustrates how chemists can change a scaffold's attachment point without rebuilding its carbon framework. The reagent is not thereby an IRAK degrader itself. Its contribution is an organized combination of shape, connection sites, and selective protection. The larger molecule's performance still depends on the complete structure and experimental evaluation, rather than the spiro label alone.