6802-75-1Relevant articles and documents
Racemic synthesis and solid phase peptide synthesis application of the chimeric valine/leucine derivative 2-amino-3,3,4-trimethyl-pentanoic acid
Pelà,Del Zoppo,Allegri,Marzola,Trapella,Ruzza,Calo,Perissutti,Frecentese,Salvadori,Guerrini, Remo
, p. 496 - 499 (2014)
The synthesis of non natural amino acid 2-amino-3,3,4-trimethyl-pentanoic acid (Ipv) ready for solid phase peptide synthesis has been developed. Copper (I) chloride Michael addition, followed by a Curtius rearrangement are the key steps for the Ipv synthesis. The racemic valine/leucine chimeric amino acid was then successfully inserted in position 5 of neuropeptide S (NPS) and the diastereomeric mixture separated by reverse phase HPLC. The two diastereomeric NPS derivatives were tested for intracellular calcium mobilization using HEK293 cells stably expressing the mouse NPS receptor where they behaved as partial agonist and pure antagonist.
Metal bridging for directing and accelerating electron transfer as exemplified by harnessing the reactivity of AIBN
Xie, Yinjun,Guo, Shengmei,Wu, Longmin,Xia, Chungu,Huang, Hanmin
supporting information, p. 5900 - 5904 (2015/05/13)
A new strategy for tuning the electron transfer between radicals and enolates has been developed. This method elicits the innate reactivity of AIBN with a copper catalyst and enables a cascade reaction with cinnamic acids. Electron paramagnetic resonance studies and control experiments indicate that the redox-active copper species not only activates the radical by coordination, but also serves as a bridge to bring the radical and nucleophile within close proximity to facilitate electron transfer. By exploiting possible combinations of redox-active metals and radical entities with suitable coordinating functional groups, this strategy should contribute to the development of a broad range of radical-based reactions.
Selective sulfenylative desulfonylation or decarbalkoxylation of α-sulfonyl malonates with DABCO or Bu3N: Reactivity and conformational analysis
Donnici, Claudio L.,Pereira, Elaine Henriques Teixeira,Lopes, Julio C. Dias,Marzorati, Liliana,Wladislaw, Blanka
scheme or table, p. 342 - 350 (2010/04/04)
The study on reactivity of severalαsubstituted αsulfonyl malonates toward 1,4-diazabicyclo[2.2.2]octane (DABCO) and Bu3N is described. The reactivity with DABCO revealed the possible competition between decarbalkoxylation and unexpected desulfonylation, depending on the-substituent, because of sterical hindrance around the electrophilic centers (SO2 and CO2R). The derivatives with crowded α-substituents suffer selective desulfonylation, and a novel and efficient desulfonylation method can be proposed. The dependence of the reactivity ofα-sulfonyl malonates on the sterical hindrance around the electrophilic centers is confirmed by conformational analysis (Macromodel/MM2* and Mopac/MP3). The carbanionic mechanism is proved because the corresponding protonated, deuterated, and sulfenylated products were obtained by addition of the corresponding electrophilic agents. Bu3N showed itself to be a novel selective decarbalkoxylation agent for any-substituted-sulfonyl malonate.
