6404-28-0Relevant articles and documents
General Access to Modified α-Amino Acids by Bioinspired Stereoselective γ-C?H Bond Lactonization
Vicens, Laia,Bietti, Massimo,Costas, Miquel
supporting information, p. 4740 - 4746 (2020/12/25)
α-Amino acids represent a valuable class of natural products employed as building blocks in biological and chemical synthesis. Because of the limited number of natural amino acids available, and of their widespread application in proteomics, diagnosis, drug delivery and catalysis, there is an increasing demand for the development of procedures for the preparation of modified analogues. Herein, we show that the use of bioinspired manganese catalysts and H2O2 under mild conditions, provides access to modified α-amino acids via γ-C?H bond lactonization. The system can efficiently target 1°, 2° and 3° γ-C?H bonds of α-substituted and achiral α,α-disubstituted α-amino acids with outstanding site-selectivity, good to excellent diastereoselectivity and (where applicable) enantioselectivity. This methodology may be considered alternative to well-established organometallic procedures.
AMINO ACID ANALOGUES AND METHODS FOR THEIR SYNTHESIS
-
Page/Page column 48; 50, (2014/01/18)
A method for the synthesis of an amino acid analogue or a salt, solvate, derivative, isomer or tautomer thereof comprising the steps of: (i) subjecting an amino acid containing a metathesisable group to metathesis with a compound containing a complementary metathesisable group of formula (I) or (II): (Formulae (I), (II)) wherein R1 and R2 are independently selected from H and substituted or unsubstituted C1 to C4 alkyl; each R3 is either absent or independently selected from a heteroatom, a substituted or unsubstituted C1 to C20 alkyl, and a substituted or unsubstituted C1 to C20 alkyl group interrupted by one or more heteroatoms; and each X is independently selected from H and an effector molecule; in the presence of a reagent to catalyse the metathesis to form a dicarba bridge between the amino acid containing a metathesisable group and the compound containing a complementary metathesisable group; and (ii) reducing the dicarba bridge to form a saturated dicarba bridge, wherein the reagent used to catalyse step (i) also catalyses step (ii).
Enzymatic approach to both enantiomers of N-Boc hydrophobic amino acids
Agosta, Eleonora,Caligiuri, Antonio,D'Arrigo, Paola,Servi, Stefano,Tessaro, Davide,Canevotti, Renato
, p. 1995 - 1999 (2007/10/03)
Protease catalysed hydrolysis of N-Boc-amino acid esters allows us to obtain N-Boc l-acids and d-esters of amino butanoic acid, nor-leucine, nor-valine, leucine and t-leucine in excellent ee. The reaction occurs in short reaction times and high concentrations. When a biphasic system (buffer-MTBE) is employed, a strong solvent effect is observed. This method could be of significance for the preparation of d-t-leucine, for which a practical method is currently unavailable.