13992-70-6Relevant academic research and scientific papers
Toward design of a practical methodology for stereocontrolled synthesis of χ-constrained pyroglutamic acids and related compounds. Virtually complete control of simple diastereoselectivity in the Michael addition reactions of glycine Ni(II) complexes with N-(enoyl)oxazolidinones
Soloshonok, Vadim A.,Cai, Chaozhong,Hruby, Victor J.
, p. 135 - 139 (2000)
A Ni(II) complex of the Schiff base of glycine with o-[N-α- picolylamino]benzophenone or -acetophenone as a nucleophilic glycine equivalent, and N-trans-enoyloxazolidinones, as a derivative of an α,β- unsaturated carboxylic acid, were found to be the substrates of choice in the corresponding Michael addition reactions. The reactions proceed at room temperature in the presence of catalytic amounts of DBU to afford quantitatively a virtually diastereocomplete formation of the corresponding addition products with (2R*,3R*) or (2R*,3S*) relative configuration, depending on the nature of the starting N-enoyloxazolidinones, Acidic decomposition of the products followed by treatment of the reaction mixture with NH4OH gives rise to the corresponding diastereomerically pure 3- substituted pyroglutamic acids.
Multicomponent synthesis of pyroglutamic acid derivatives: Via Knoevenagel-Michael-hydrolysis-lactamization-decarboxylation (KMHL-D) sequence
Khopade, Tushar M.,Warghude, Prakash K.,Sonawane, Amol D.,Bhat, Ramakrishna G.
supporting information, p. 561 - 566 (2019/01/24)
A novel and practical method for the synthesis of 3-substituted pyroglutamic acid derivatives is described. One pot multicomponent reaction of Meldrum's acid, aldehyde and Schiff's base followed an unprecedented chemoselective Knoevenagel-Michael-hydrolysis-lactamization domino sequence to afford 4-carboxy 3-substituted pyroglutamic acid derivatives under mild conditions. A carboxy intermediate formed appears to accelerate its own formation. The generality of the synthesis is exemplified by the use of a wide variety of aldehydes including enolizable aliphatic aldehydes, while substrates are stable under reaction conditions.
Rational Design of Highly Diastereoselective, Organic Base-Catalyzed, Room-Temperature Michael Addition Reactions
Soloshonok, Vadim A.,Cai, Chaozhong,Hruby, Victor J.,Van Meervelt, Luc,Yamazaki, Takashi
, p. 6688 - 6696 (2007/10/03)
Via the rational design of a single-preferred transition state, stabilized by electron donor - acceptor-type attractive interactions, structural and geometric requirements for the corresponding starting compounds have been determined. The Ni(II) complex of the Schiff base of glycine with o-[N-α-picolylamino]acetophenone, as a nucleophilic glycine equivalent, and N-(trans-enoyl)oxazolidin-2-ones, as derivatives of an α,β-unsaturated carboxylic acid, were found to be the substrates of choice featuring geometric/conformational homogeneity and high reactivity. The corresponding Michael addition reactions were found to proceed at room temperature in the presence of catalytic amounts of DBU to afford quantitatively the addition products with virtually complete diastereoselectivity. Acidic decomposition of the products followed by treatment of the reaction mixture with NH4OH gave rise to the diastereomerically pure 3-substituted pyroglutamic acids.
