180922-44-5Relevant articles and documents
Common precursor strategy for the synthesis of bestatin, amprenavir intermediate and syn-4-hydroxy-5-phenyl-γ-lactam
Kumar, Brijesh,Aga, Mushtaq A.,Rouf, Abdul,Shah, Bhahwal A.,Taneja, Subhash C.
, p. 17206 - 17209 (2014/05/06)
A common precursor strategy for the synthesis of bestatin hydrochloride, an anticancer agent, 1,3-diaminoalcohol, an amprenavir intermediate, and a syn-4-hydroxy-5-phenyl-γ-lactam intermediate of various bioactive molecules using an α,β-unsaturated ester as a common precursor is described. The protocol offers mild reaction conditions, good yields and excellent stereoselectivity.
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.
