162518-07-2Relevant academic research and scientific papers
104. The enantioselective synthesis of β-amino acids, their α-hydroxy derivatives, and the N-terminal components of bestatin and microginin
Jefford, Charles W.,McNulty, James,Lu, Zhi-Hui,Wang, Jian Bo
, p. 1203 - 1216 (2007/10/03)
L-Aspartic acid by tosylation, anhydride formation, and reduction with NaBH4 was converted into (3S)-3-(tosylamino)butan-4-olide (8; Scheme 1). Treatment of 8 with ethanolic trimethylsilyl iodide gave the N-protected deoxy-iodo-β-homoserine ethyl ester 9. The latter, on successive nucleophilic displacement with lithium dialkylcuprates (→ 10a-e), alkaline hydrolysis (→ 11a-e), and reductive removal of the tosyl group, produced the corresponding 4-substituted (3R)-3-aminobutanoic acids 12a-e (ee >99%). Electrophilic hydroxylation of 8 (→ 19; Scheme 3), subsequent iodo-esterification (→ 21; Scheme 4), and nucleophilic alkylation and phenylation afforded, after saponification and deprotection, a series of 4-substituted (2S,3A)-3-amino-2-hydroxybutanoic acids 24 including the N-terminal acids 24e (= 3) and 24f (= 4) of bestatin and microginin (de >95%), respectively.
A Concise Enantioselective Synthesis of N-Morpholinosphingosines from D-Aspartic Acid
Jefford, Charles W.,McNulty, James,Lu, Zhi-Hui
, p. 123 - 124 (2007/10/02)
D-Aspartic acid, by N-tosylation, anhydride formation, reduction, α-hydroxylation and iodo-esterification, gives ethyl (2R,3R)-3--2-hydroxy-4-iodobutyrate which, by treatment with morpholine, silylation, DIBAH reduction, Wittig reaction an
A concise diastereospecific synthesis of 3-amino-2-hydroxy acids
Jefford,Wang,Lu
, p. 7557 - 7560 (2007/10/02)
L-Aspartic acid by N-tosylation, anhydride formation, reduction, α-hydroxylation, iodo esterification and alkylation followed by saponification and deprotection afforded a series of 4-alkyl-3-amino-2-hydroxybutyric acids having the 2S,3R configuration (de
