Sandwich, United Kingdom
Sandwich, United Kingdom

Time filter

Source Type

Gu J.,Pfizer | Storz T.,Chemical Research and Development | Vyverberg F.,Chemical Research and Development | Wu C.,Kilolab Facilities | And 2 more authors.
Organic Process Research and Development | Year: 2011

A practical, robust, and high-yielding three-step-one-pot procedure for the diastereoselective synthesis of (±)-2-exo-norbornyl carboxylic acid starting from norbornylene has been found and demonstrated on multikilogram scale, setting a new benchmark for low-pressure hydroformylation of cyclic, bridged olefins. The newly found, nonhygroscopic crystalline sodium salt of this acid provides a practical isolation point. © 2011 American Chemical Society.


Peng Z.,Pfizer | Ragan J.A.,Pfizer | Colon-Cruz R.,Pfizer | Conway B.G.,Pfizer | And 14 more authors.
Organic Process Research and Development | Year: 2014

This paper describes an improved sequence for the conversion of an oxazolidinone (3) to a β-keto lactone (5). The primary drivers behind this change were the modest and variable yields observed in the intramolecular cyclization to generate the β-keto lactone. Changing the cyclization substrate from oxazolidinone to alkyl ester offered a significantly improved cyclization, as well as improvements in the alkyne hydrogenation. Selection of the optimal substrates for methanolysis and intermediate salt formation are also described. © 2013 American Chemical Society.


Brenek S.J.,Chemical Research and Development | Caron S.,Chemical Research and Development | Chisowa E.,Chemical Research and Development | Chisowa E.,Pfizer | And 17 more authors.
Organic Process Research and Development | Year: 2012

The research, development, and scale-up of the broad-spectrum antibacterial candidate sulopenem are presented. An enabled medicinal chemistry synthesis of this active pharmaceutical ingredient was utilized for Phase 1 and early Phase 2 manufacture but was not conducive to larger scale. The limitations associated with the first-generation synthesis were partially addressed in an improved second-generation synthesis of the target molecule where the penem ring is constructed via a modified Eschenmoser sulfide contraction sequence. Other highlights of the second-generation process include an improved synthesis of an important trithiocarbonate intermediate and a superior process for Pd-catalyzed deallylation of the penultimate ester to obtain low levels of residual palladium. © 2012 American Chemical Society.


Brenek S.J.,Chemical Research and Development | Caron S.,Chemical Research and Development | Chisowa E.,Chemical Research and Development | Chisowa E.,Pfizer | And 14 more authors.
Organic Process Research and Development | Year: 2012

Previous synthetic processes for the preparation of sulopenem involved multistep linear sequences in which the chiral sulfoxide side chain was introduced early in the process. This contribution summarizes the development of a practical and convergent process for the large-scale preparation of 1. The key step in the synthesis involves cyclization of an oxalimide intermediate to provide the thiopenem core. This convergent strategy allows for late introduction of the expensive and labile chiral sulfoxide subunit. Additionally, a regioselective sulfur oxidation and an improved deprotection sequence were developed. The latter provides API of high purity without the need for recrystallization. © 2012 American Chemical Society.

Loading Chemical Research and Development collaborators
Loading Chemical Research and Development collaborators