203869-80-1Relevant articles and documents
Interrupted Curtius Rearrangements of Quaternary Proline Derivatives: A Flow Route to Acyclic Ketones and Unsaturated Pyrrolidines
Baumann, Marcus,Moody, Thomas S.,Smyth, Megan,Wharry, Scott
, p. 14199 - 14206 (2021/07/20)
Conversion of N-Boc-protected quaternary proline derivatives under thermal Curtius rearrangement conditions was found to afford a series of ring-opened ketone and unsaturated pyrrolidine products instead of the expected carbamate species. The nature of the substituent on the quaternary carbon thereby governs the product outcome due to the stability of a postulated N-acyliminium species. A continuous flow process with in-line scavenging was furthermore developed to streamline this transformation and safely create products on a gram scale.
Design and Synthesis of 56 Shape-Diverse 3D Fragments
Atobe, Masakazu,Blakemore, David C.,Bond, Paul S.,Chan, Ngai S.,De Fusco, Claudia,Downes, Thomas D.,Firth, James D.,Hubbard, Roderick E.,Jones, S. Paul,Klein, Hanna F.,O'Brien, Peter,Roughley, Stephen D.,Vidler, Lewis R.,Waddelove, Laura,Whatton, Maria Ann,Wheldon, Mary C.,Woolford, Alison J.-A.,Wrigley, Gail L.
, (2020/07/13)
Fragment-based drug discovery is now widely adopted for lead generation in the pharmaceutical industry. However, fragment screening collections are often predominantly populated with flat, 2D molecules. Herein, we describe a workflow for the design and synthesis of 56 3D disubstituted pyrrolidine and piperidine fragments that occupy under-represented areas of fragment space (as demonstrated by a principal moments of inertia (PMI) analysis). A key, and unique, underpinning design feature of this fragment collection is that assessment of fragment shape and conformational diversity (by considering conformations up to 1.5 kcal mol?1 above the energy of the global minimum energy conformer) is carried out prior to synthesis and is also used to select targets for synthesis. The 3D fragments were designed to contain suitable synthetic handles for future fragment elaboration. Finally, by comparing our 3D fragments with six commercial libraries, it is clear that our collection has high three-dimensionality and shape diversity.
Structure-reactivity relationships of l-proline derived spirolactams and α-methyl prolinamide organocatalysts in the asymmetric Michael addition reaction of aldehydes to nitroolefins
Kelleher, Fintan,Kelly, Sinead,Watts, John,McKee, Vickie
experimental part, p. 3525 - 3536 (2010/06/17)
l-Proline derived spirolactams and α-methyl prolinamides act as organocatalysts for the asymmetric conjugate addition of aldehydes to nitroolefins in excellent yields, with good diastereoselectivity and enantioselectivity. Furthermore, low catalyst loadings (5 mol %) and a low aldehyde molar excess (1.5 M equiv) were achieved.
Direct synthesis of Boc protected (D,L)-amino acids from Boc-glycine
De Nicola,Einhorn,Luche
, p. 6461 - 6464 (2007/10/02)
Boc-glycine is easily deprotonated by lithium diisopropylamide, yielding a trianion which is trapped with an electrophile to give access to Boc-(D,L)-amino acids.
