Polyenolates of Unsaturated Carboxylic Acids in Synthesis. Synthesis of Unsaturated α-Amino Acids and β-Hydrazing Acids
摘要:
Regioselective reaction of lithium dieneand triene-diolates 1 and 2 with o-diphenylphosphinyl hydroxylamine affords unsaturated alpha-amino acids 3 and 4. Addition to DEAD leads selectively to gamma-hydrazino unsaturated acids 5 and 6.
enhancement: The X‐ray crystal structure of an arylmalonatedecarboxylase (AMDase) with a mechanism‐based inhibitor bound to an active‐site dioxyanion hole provides insight into the mechanism of this intriguing enzyme. The structure also guided the extension of the AMDase biocatalytic repertoire to include a wide range of α‐alkenyl as well as α‐arylmalonates.
Flame-induced reactions of sulfur-containing amino acids in an aqueous solution
作者:Shinya Nomoto、Akira Shimoyama、Susumu Shiraishi
DOI:10.1016/s0040-4039(97)10802-4
日期:1998.2
Hydrogen-oxygen flames, when blown against an aqueous solution of methionine, induced conversion reactions to homoserine, 2-aminobutyric acid and glutamic acid. Besides the already-known reactions by a hydroxyl radical, a contribution of a hydrogen atom from hydrogen-rich flames to the reaction was recognized. We successfully controlled the vigorous oxidation of the system using a radical scavenger
FLAME-INDUCED CARBOXYLATION OF UNSATURATED AMINES IN AN AQUEOUS FORMIC ACID SOLUTION
作者:Shinya Nomoto、Kaoru Harada
DOI:10.1246/cl.1985.145
日期:1985.1.5
When a hydrogen-oxygen flame was kept in contact with an aqueous formicacid solution of unsaturatedamines, carboxylation onto a double bond took place. This reaction revealed to be initiated by addition of a hydrogen atom to the double bond followed by coupling of the resulted substrate radical with a carboxyl radical.
There is provided a method of producing at least one unsaturated amino acid from at least one amino acid comprising at least two carbonyl groups, the method comprising (a) contacting a recombinant microbial cell with a medium comprising the amino acid comprising the carbonyl groups, wherein the cell is genetically modified to comprise -at least a first genetic mutation that increases the expression relative to the wild type cell of an enzyme (E) selected from the CYP152 10 peroxygenase family, and -at least a second genetic mutation that increases the expression relative to the wild type cell of at least one NAD(P)+ oxidoreductase (E2) and the corresponding mediator protein.
A new highlyenantioselective route to α-alkenyl α-amino acid derivatives, which are important naturally occurring compounds with attractive bioactivity and synthetic utility, was developed using a N–H insertion reaction of vinyldiazoacetates and tert-butyl carbamate cooperatively catalyzed by achiral dirhodium(II) carboxylates and chiral spiro phosphoric acids under mild, neutral conditions. This