105469-00-9

Upstream product

• 35373-92-3 L-phenylalanine methylamide 
• 17186-56-0 L-phenylalanine methylamide hydrochloride 
• 13734-34-4 N-tert-butoxycarbonyl-L-phenylalanine 
• 109522-21-6 N-(t-butoxycarbonyl)-L-phenylalanine methylamide 
• 87877-11-0 Phe-Chlor 
• 63-91-2 L-phenylalanine 

Downstream Products

• 1407153-97-2 (-)-(4S)-4-benzyl-1-methyl-3-(4-nitrophenyl)imidazolidin-2-one 

Relevant academic research and scientific papers

Divergent 2-Chloroquinazolin-4(3H)-one Rearrangement: Twisted-Cyclic Guanidine Formation or Ring-Fused N-Acylguanidines via a Domino Process

A highly efficient 2-chloroquinazolin-4(3H)-one rearrangement was developed that predictably generates either twisted-cyclic or ring-fused guanidines in a single operation, depending on the presence of a primary versus secondary amine in the accompanying diamine reagent. Exclusive formation of twisted-cyclic guanidines results from pairing 2-chloroquinazolinones with secondary diamines. Use of primary amine-containing diamines permits a domino quinazolinone rearrangement/intramolecular cyclization, gated through (E)-twisted-cyclic guanidines, to afford ring-fused N-acylguanidines. This scalable, structurally tolerant transformation generated 55 guanidines and delivered twisted-cyclic guanidines with robust plasma stability and an abbreviated total synthesis of an antitumor ring-fused guanidine (4 steps, 55 % yield).

Application of aziridinium ring opening for preparation of optically active diamine and triamine analogues: highly efficient synthesis and evaluation of DTPA-based MRI contrast enhancement agents

Ring opening of aziridinium ions with nitrogen nucleophiles was applied to the highly efficient synthesis of optically active vicinal diamines and diethylene triamine pentaacetic acid (DTPA) analogues as potential magnetic resonance imaging (MRI) contrast enhancement agents. The synthetic method features a column-free isolation of the regiospecific and stereospecific nucleophilic substitution products of enantiomerically enriched aziridinium ions in excellent yield.

Methylene-bridged bis(imidazoline)-derived 2-oxopyrimidinium salts as catalysts for asymmetric Michael reactions

In nothing flat: The title salts, having planar nitrogen centers, were utilized successfully as phase-transfer catalysts for asymmetric Michael reactions of tert-butyl glycinate benzophenone Schiff base with vinyl ketone and chalcone derivatives, thus providing excellent levels of diastereo- and enantiocontrol (see scheme). Copyright

New chiral zwitterionic phosphorus heterocycles: Synthesis, structure, properties and application as chiral solvating agents

A family of new chiral zwitterionic phosphorus-containing heterocycles (zPHC) have been derived from methylene-bridged bis(imidazolines). These structures were unambiguously determined, including single-crystal XRD analysis for two compounds. The stability, acid/base and electronic properties of these dipolar phosphorus heterocycles were subsequently investigated. zPHCs can be successfully employed as a new class of chiral solvating agents for the enantiodifferentiation of chiral carboxylic and sulfonic acids by NMR spectroscopy. The stoichiometry and binding constants for the donor-acceptor complexes formed were established by NMR titration methods. A convenient synthetic approach to a new class of chiral zwitterionic phosphorus-containing heterocycles starting from methylene-bridged bis(imidazolines) was designed and executed. Stability and properties of the synthesized compounds were investigated. The applicability of the designed compounds as chiral solvating agents for the determination of the enantiomeric excesses of chiral acids was demonstrated. Copyright

Organocatalyzed highly enantioselective michael additions of malonates to enones by using novel primary-secondary diamine catalysts

A novel primary-secondary diamine catalyst readily available from primary amino acids in three steps for the highly enantioselective Michael additions of malonates to α,β-unsaturated ketones was reported. The Michael reaction of dimethyl malonate with benzylideneacetone was selected as a model reaction for catalyst evaluation. The length of the alkyl chain is found to influence the catalytic abilities of the catalysts and the n-propylated catalyst gave the highest yield and ee value. The addition of a series of malonates to enone performed under the optimized conditions is found to be sensitive to the steric hinderance on the malonates. Heterocyclic furan enone is found to perform well to give the desired product in 92% yield and 99% ee, while no decrease in yield and ee value is observed for sterically hindered enone.

Organocatalytic asymmetric conjugate addition of nitroalkanes to α,β-unsaturated enones using novel imidazoline catalysts

A new catalytic enantioselective conjugate addition of nitroalkanes to acyclic α,β-unsaturated enones catalyzed by novel organic catalysts has been developed. A series of chiral amines has been tested as catalysts for the addition of 2-nitropropane to benzylideneacetone, and it is found that a novel imidazoline catalyst, prepared from phenylalanine, can catalyze a highly enantioselective 1,4addition reaction. The reaction of various acyclic and cyclic nitroalkanes was found to proceed well with enantioselectivities up to 86% ee, and enantiopure products can be obtained by recrystallization. The potential of the reaction is documented by the reaction of a series of substituted α,β-unsaturated enones with different nitroalkanes. Furthermore, the synthetic applicability of the reaction is demonstrated by the formation of optically active functionalized pyrrolines and pyrrolidines by reductive amination of the products. On the basis of the absolute configuration of the conjugate addition products, the mechanism for the reaction is discussed and a transition state proposed.