Straightforward preparation of labeled potassium cyanate by ozonation and application to the synthesis of [<sup>13</sup>C] or [<sup>14</sup>C]ureidocarboxylic acids
作者:Olivier Loreau、Philippe Marlière
DOI:10.1002/jlcr.3041
日期:2013.6.15
The development of new efficient syntheses of labeled reagents is a great challenge. Avoidance of overcomplicated procedures, availability and cost of starting materials are important considerations in choosing the synthetic route. In this report, we describe a facile and rapid preparation of labeled cyanate by ozonation of cyanide, a basic precursor. The crude cyanate was used without purification for the synthesis of various [13C] or [14C]ureidocarboxylic acids (20-68% yield from potassium cyanide). According to these results, cyanide ozonation may prove to be a promising alternative to traditional preparations of labeled cyanate.
Synthesis of 1S,5R- and 1R,5S-glycoluriles by diastereospecific α-ureidoalkylation of (S)/(R)-N-carbamoyl-α-amino acids with 4,5-dihydroxyimidazolidin-2-one
作者:Il’ya E. Chikunov、Angelina N. Kravchenko、Pavel A. Belyakov、Konstantin A. Lyssenko、Vladimir V. Baranov、Oleg V. Lebedev、Nina N. Makhova
DOI:10.1070/mc2004v014n06abeh002050
日期:2004.1
A diastereospecific method for the synthesis of individual enantiomers of 1S,5R- and 1R,5S-glycoluriles has been developed based on the α-ureidoalkylation of (S)/(R)-N-carbamoyl-α-amino acids with 4,5-dihydroxyimidazolidin-2-one.
Methods for producing single diastereomers of isoleucine in high stereochemical purity are provided. D-isoleucine is produced by converting (R)-2-methylbutyraldehyde to a diastereomeric mixture of D-isoleucine hydantoin and L-allo-isoleucine hydantoin (5S-[(R)-1-methylpropyl]hydantoin) under conditions whereby no significant racemization of the chiral center in (R)-2-methylbutyraldehyde occurs, followed by contacting said diastereomeric hydantoin mixture with a D-hydantoinase to stereoselectively hydrolyze any D-isoleucine hydantoin in the mixture to the corresponding N-carbamoyl-D-isoleucine, preferably under conditions permitting the simultaneous epimerization of the chiral center at C-5 of the hydantoin. The simultaneous epimerization permits the reaction to be carried out to substantial completion so that the diastereomeric hydantoin mixture is converted to N-carbamoyl-D-isoleucine in high yield. The N-carbamoyl-D-isoleucine is then decarbamoylated to produce D-isoleucine. Similar procedures are used to produce single diastereomers of L-isoleucine, L-allo-isoleucine, and D-allo-isoleucine.
PROCESS FOR PRODUCING D-N-CARBAMOYL-$g(a)-AMINO ACID
申请人:Kanegafuchi Chemical Industry Co., Ltd.
公开号:EP0801131A1
公开(公告)日:1997-10-15
A process for producing D-N-carbamoyl-α-amino acid from a 5-substituted hydantoin with the use of a hydantoinase produced by a microorganism transformed with a recombinant DNA with a vector DNA and the fragments of a DNA containing genes associated with a hydantoinase originating in a specified microorganism belonging to the genus Bacillus, Agrobacterium or Pseudomonas.
一种用 5-取代的海因生产 D-N-氨基甲酰-α-氨基酸的工艺,该工艺使用的海因酶是由重组 DNA 转化的微生物产生的,重组 DNA 的载体 DNA 和 DNA 片段含有与海因酶相关的基因,这些基因来源于属于芽孢杆菌属、农杆菌属或假单胞菌属的特定微生物。
STEREOSTRUCTURE OF DECARBAMYLASE AND METHOD OF USING THE SAME
申请人:Kaneka Corporation
公开号:EP1209234A1
公开(公告)日:2002-05-29
The present invention reveals the stereostructure of decarbamylase by X-ray crystallography and provides a decarbamylase mutant, which is more useful for industrial applications, obtained by molecular design utilizing the stereostructure for the purpose of improving the reactivity of decarbamylase to D-N-carbamoyl-α-amino acid which is a substrate thereof. Specifically, the present invention relates to the stereostructure of decarbamylase determined by X-ray crystallography; a stereostructure model of a decarbamylase mutant; a stereostructure model of a complex thereof with a substrate, a product, and the like; a molecular design method utilizing these stereostructures; a decarbamylase mutant obtained by the method; and a method for designing and producing a protein mutant having a structure similar to that of decarbamylase.
本发明通过X射线晶体学揭示了脱氨基甲酰酶的立体结构,并提供了一种脱氨基甲酰酶突变体,该突变体通过利用该立体结构进行分子设计而获得,更有利于工业应用,其目的是提高脱氨基甲酰酶对作为其底物的D-N-氨基甲酰-α-氨基酸的反应活性。具体而言,本发明涉及通过 X 射线晶体学确定的脱氨基甲酰酶的立体结构;脱氨基甲酰酶突变体的立体结构模型;其与底物、产物等的复合物的立体结构模型;利用这些立体结构的分子设计方法;通过该方法获得的脱氨基甲酰酶突变体;以及设计和生产具有与脱氨基甲酰酶相似结构的蛋白质突变体的方法。