L-Histidine methyl ester

A/- -toluene su1fony1)-T-phenylalanine (62), L-histidine methyl ester (63), A/-acetyl L-valine /-butyl amide (64), etc, are used as chiral addends. 

Figure 8.43 Separation of enantiomers using complexation chromatography. A, Separation of alkyloxiranes on a 42 m x 0.2S mm I.O. open tubular column coated with 0.06 M Mn(II) bis-3-(pentafluoro-propionyl)-IR-camphorate in OV-ioi at 40 C. B, Separation of D,L-amino acids by reversed-phase liquid chromatography using a mobile phase containing 0.005 M L-histidine methyl ester and 0.0025 M copper sulfate in an ammonium acetate buffer at pH 5.5. A stepwise gradient using increasing amounts of acetonitrile was used for this separation.

Another example, which demonstrates the modulation of the peroxidase activity of Mb by modification of the heme-propionate side chains, has been proposed by Casella and co-workers (75). They prepared a Mb reconstituted with peptide-linked hemin such as protohemin-L-arginyl-L-alanine or protohe-min-L-histidine methyl ester as shown in Fig. 20. The peroxidase activity toward small substrate oxidations by the reconstituted Mb slightly increased the fccat... 

Hydroxyethylmethacrylate -I- N-methacryloyl-(L)-histidine methyl ester -l- A,W -methylene-bis-acrylamide... 

Optically active compounds. Triethylamine added with stirring and ice-cooling to L-histidine methyl ester dihydrochloride in abs. chloroform, after 15 min. p-toluenesulfonyl chloride added to the resulting suspension so slowly that the temp, does not exceed 15°, stirring continued without cooling, and the product isolated after several hrs. N,N-ditosyl-L-histidine methyl ester (Y 75%) suspended in N NaOH, and stirred 30 min. at 60° tosyl-L-histidine monohydrate (Y 87%). B. Helferich and H. Bdshagen, B. 92, 2813 (1959). 

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