105743-53-1Relevant articles and documents
Asymmetric synthesis of (S)-α-methyl α-amino acids by alkylation of chiral 3,6-dihydro-2h-1,4-oxazin-2-ones using unactivated alkyl halides and organic bases
Chinchilla, Rafael,Galindo, Nuria,Najera, Carmen
, p. 2769 - 2772 (1998)
3,6-Dihydro-2H-1,4-oxazin-2-ones 1 have been diastereoselectively (>96% de) alkylated using unactivated alkyl halides and organic bases such as 2- tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine (BEMP) or 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) at room temperature in the presence of LiI. Hydrolysis of the resulting alkylated systems afforded enantiomerically enriched (S)-α-methyl α-amino acids. When 1,3- diiodopropane was used, spontaneous N-alkylation also took place giving bicyclic oxazinone 6 which was hydrolyzed to (S)-α-methylproline.
METHOD FOR PRODUCING AMINO ACID AND AMINO ACID SYNTHESIS KIT
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Paragraph 0130-0133, (2017/04/03)
PROBLEM TO BE SOLVED: To provide a method for producing an amino acid and an amino acid synthesis kit, which enable synthesis of a desired amino acid in high stereoselectivity efficiently and in a very short time, irrespective whether a radioactive isotope is contained or not. SOLUTION: A method for producing an amino acid and an amino acid synthesis kit are disclosed. The method for producing an amino acid of the present invention comprises a step of alkylating a substrate compound with an alkylating agent in the presence of an optically active phase transfer catalyst as well as a medium and an inorganic base. An amount of use of the optically active phase transfer catalyst is 1 equivalent or more and 1000 equivalents or less relative to the alkylating agent. According to the present invention, a desired amino acid and a derivative thereof can be produced in high stereoselectivity efficiently and in a very short time. Therefore, the present production method is useful, for example, for research and development, and production of a radioactively labelled amino acid and a derivative thereof, which can be used as a tracer for neurodegenerative diseases such as Parkinson disease and Alzheimer disease, heart diseases, and cancerous diseases. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
Asymmetric synthesis of α-methyl-α-amino acids via diastereoselective alkylation of (1s)-(+)-3-carene derived tricyclic iminolactone
Lu, Ta-Jung,Lin, Cheng-Kun
experimental part, p. 1621 - 1633 (2011/06/17)
A novel carene-based alanine-equivalent tricyclic iminolactone 16 has been synthesized via stereoselective dihydroxylation of the double bond, IBX oxidation of the secondary alcohol, esterification of the tertiary alcohol, deprotection of the resulting ester, and subsequent cyclization from commercially available (1S)-(+)-3-carene in 79% overall yield. The iminolactone 16 demonstrated high reactivity toward alkylation with a wide range of electrophiles at room temperature under phasetransfer catalysis conditions. The alkylated products were produced with excellent diastereoselectivities (>98% de) in good isolated yields (86-94%). High yields (83-91%) of optically pure (S)-R-methyl-R-substituted-R-amino acids were obtained by basic hydrolysis of the dialkylated iminolactones with the recovery of the chiral auxiliary 15 (78-87%).