(S)-2-((tert-Butoxycarbonyl)amino)-3,3-dicyclopropylpropanoic acid

CAS 2548967-22-0

The S label records something molecular mass cannot reveal: the chosen handed form. CAS 2548967-22-0 is a Boc-protected amino acid with an S-configured alpha carbon and two cyclopropyl groups on its side chain. A patent describes obtaining the S acid from a selected ester enantiomer, coupling the acid to an amino-containing heterocycle, then exposing the original nitrogen for further construction. Chiral selection and functional-group protection control different parts of that sequence. The starting acid is a defined building block, not automatically an IL-17 inhibitor. Equal formulas and masses also do not make it interchangeable with an entry lacking an S or R designation. Its useful contribution is preserving stereochemical information and connection points as a larger research molecule is assembled.