3-[(2S,4S)-4-Mercaptopyrrolidine-2-carboxamido]benzoic acid hydrochloride

Ertapenem side-chain II is the hydrochloride of 3-[(2S,4S)-4-mercaptopyrrolidine-2-carboxamido]benzoic acid. It introduces the stereodefined pyrrolidine–aminobenzoic-acid fragment and provides a thiol group for attachment to the carbapenem nucleus. These two features preserve the side-chain configuration and enable formation of the thioether bond required in ertapenem.

The selected version has a free thiol and benzoic acid group and is isolated as a hydrochloride; it is not a Boc-protected pyrrolidine or a benzoate ester. That identity determines its position in an ertapenem synthesis sequence. Its existing amide bond connects the aromatic acid and pyrrolidine portions before core coupling, reducing the need to construct this side-chain framework after attachment to the sensitive beta-lactam system.

Typical Applications

• Ertapenem thioether coupling: Used as the thiol-bearing side chain in reaction with an activated carbapenem intermediate, installing the stereodefined pyrrolidine substituent through a carbon–sulfur bond.
• Side-chain protection and route development: Used in ertapenem process sequences that prepare protected derivatives or evaluate coupling with the unprotected side chain, retaining the aromatic carboxyl group and the specified pyrrolidine configuration.

Specifications

Specifications describe the standard grade. Tolerance, test method and documentation package are confirmed per order.