Synthesis of bis-α-amino acids through proline catalyzed asymmetric α-amination of higher homologs of Garner's aldehyde

Synthesis and applications of symmetric amino acid derivatives

“…compound 45) and 2,6diaminopimelic acid derivatives through cross-metathesis. 19 A photo-irradiated dimerization was reported by Vederas et al 20 The protected (R)-glutamic acid (48) was converted to peracid via condensation with peroxide and acidic hydrolysis. After condensation with an (S)-aspartic acid derivative, the resultant diacylperoxide 50 was irradiated to convert protected meso-2,6-diaminopimelic acid 51 via decarboxylation (Scheme 5).…”

“…For example, asymmetric amination of aldehyde 159 , synthesized from ( S )-glutamic acid or ( S )-aspartic acid, proceeded under the conditions using dibenzyl azodicarboxylate in the presence of a catalytic amount of ( S )-proline followed by reduction to afford alcohol 160 in a highly diastereoselective manner (Scheme 21a). 48 After separation of diastereomers, the pure alcohol 160 was converted to protected meso bis-amino acids ( 161 ) in seven steps. Meso bis-amino acid derivatives have also been synthesized by asymmetric reduction of ( S )-aspartic acid derivatives with ( R )-(+)-Alpine borane to form a second chiral centre and by using asymmetric epoxidation to allyl alcohols prepared from ( S )-glutamic acid or ( S )-aspartic acid (b and c).…”

Diastereoselective Synthesis of (–)-Bestatin, Epibestatin, Phebestin and (3S,4R)-4-Amino-3-hydroxy-5-phenylpentanoic Acid from an Aldehyde Derived from d-Phenylalanine

“…cules, [32][33][34][35][36][37][38][39][40][41] we recently reported the synthesis of D-threosphinganine, L-erythro-sphinganine and (-)-spisulosine from an aldehyde derived from aspartic acid. 42 In the retrosynthetic analysis, it was anticipated that both bestatin and epibestatin could be synthesized from acid 9 using peptide coupling followed by deprotection of the Boc and MOM groups.…”

Synthesis of (–)-Bulgecinine and 5-epi-Bulgecinine through Proline-Catalysed Asymmetric α-Hydroxylation of an Aldehyde Derived from l-Glutamic Acid

“…The required starting material 3 is commercially available or can be readily synthesised from L-glutamic acid. [23][24][25] Aldehyde 3 was then subjected to diastereoselective -hydroxylation using nitrosobenzene, and D-proline as catalyst and the product was subsequently reduced to the corresponding primary alcohol with NaBH 4 in one pot. The crude product was further subjected to N-O bond cleavage using Cu(OAc) 2 to obtain the diol 4 in 72% overall yield.…”