- PROCESS FOR PRODUCING N-PROTECTED AMINO ACID
-
The present invention relates to a method for producing N-protected amino acid. Specifically, the present invention provides a method in which a protecting group is introduced to the amino group of an amino acid in a reaction under alkaline condition, and the N-protected amino acid thus generated is then separated from the reaction solution as crystals, without undergoing an extraction step or a concentration step. The present inventors have completed the invention based on the finding that desirable crystals of N-protected amino acids may be obtained without extraction, concentration or recrystallization steps between the initial generation of the N-protected amino acid molecules and the subsequent separation of the crystals, by first adding an water-soluble organic solvent and optionally water to the reaction solution (alkaline) containing the N-protected amino acid, and then neutralizing the solution by an acid.
- -
-
Page/Page column 3
(2011/07/06)
-
- Asymmetric hydrogenation of N-sulfonylated-α-dehydroamino acids: Toward the synthesis of an anthrax lethal factor inhibitor
-
(Chemical Equation Presented) A novel and highly enantioselective Ru-catalyzed hydrogenation of N-sulfonylated-α-dehydroamino acids has been discovered and demonstrated in the synthesis of an anthrax lethal factor inhibitor (LFI). Herein, this methodology is used to prepare N-sulfonylated amino acids in up to 98% ee. This unprecedented hydrogenation uses a chiral Ru catalyst rather than Rh as typical for acylated dehydroamino acids and esters, and this work reports the first asymmetric hydrogenation of a tetrasubstituted dehydroamino acid derivative using a Ru catalyst.
- Shultz, C. Scott,Dreher, Spencer D.,Ikemoto, Norihiro,Williams, J. Michael,Grabowski, Edward J. J.,Krska, Shane W.,Sun, Yongkui,Dormer, Peter G.,DiMichele, Lisa
-
p. 3405 - 3408
(2007/10/03)
-
