Enantioselective synthesis of the carbapenem ring system from (S)-proline

Abstract

Enantioselective synthesis of (+)-PS-5 via stereoselective alkylation of proline derivatives is described.

Stereochemical Control in Organic Synthesis Using Silicon-Containing Compounds

“…There are similar reactions with pyrrolidines 626 and piperidines 627 , also quite frequently setting up a syn relationship across the ring, as in the piperidine 628 (Scheme ).

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Free-Radical Reactions in the Synthesis of α-Amino Acids and Derivatives

“…With derivatives of diamino acids such as ornithine and lysine, oxidation can occur either at the α-position or on the side chain, depending on the conditions used (Scheme ). ,− Cyclizations of the side chain-substituted derivatives have been used for the synthesis of optically active piperidine and pyrrolidine alkaloids. ,,, In principle, electron transfer from proline derivatives, followed by proton loss, and then addition of methanol to the resultant imines, could afford products methoxylated at either the 2- or 5-position. In practice, the 5-methoxy derivatives are obtained. − Interest in these compounds in synthesis − stems from the optical activity of the proline derivatives which is retained in the products.

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Concise Synthesis and Antimicrobial Evaluation of the Guanidinium Alkaloid Batzelladine D: Development of a Stereodivergent Strategy

“…Bicyclic β-lactams are common scaffolds in antimicrobial natural products but have seen limited utility as strategic building blocks for synthesis. − As highlighted in our retrosynthetic approach, we require a [4.5]-fused bicyclic β-lactam 6 (Figure b) bearing a trans-pyrrolidine core. Straightforward methods to construct such functionalized scaffolds are not currently available, − and we therefore embarked on studies to append the requisite ring to β-lactams such as 15 . A number of approaches including aminohalogenation, aza-Heck, − amination/cross-coupling, − and carbonylative amidation , resulted in no cyclization but instead direct intermolecular reactivity (see SI for details).…”