P312：Call a POISON CENTER or doctor/physician if you feel unwell.
Description
This spirocyclic building block was first synthesized by Carreira and coworkers. It provides a new area of chemical space with straightforward functional handles for further diversification.
![tert-Butyl 8-oxo-5-thia-2-azaspiro[3.4]octane-2-carboxylate 5,5-dioxide](https://www.chemicalbook.com/CAS/GIF/1340481-91-5.gif)
