Efficient and regioselective synthesis of dihydroxy-substituted 2-aminocyclooctane-1-carboxylic acid and its bicyclic derivatives

• İlknur Polat,
• Selçuk Eşsiz,
• Uğur Bozkaya and
• Emine Salamci

Beilstein J. Org. Chem. 2022, 18, 77–85, doi:10.3762/bjoc.18.7

• -oxabicyclo[5.2.1]decan-10-yl)carbamate was confirmed by X-ray diffraction. Keywords: aminocyclitol; azidolysis; bicyclic β-lactam; bicyclic lactone; cyclic β-amino acids; DFT; Introduction Cyclic β-amino acids have for the past few decades aroused widespread synthetic interest owing to their diverse

Novel stereocontrolled syntheses of tashiromine and epitashiromine

• Loránd Kiss,
• Enikő Forró and
• Ferenc Fülöp

Beilstein J. Org. Chem. 2015, 11, 596–603, doi:10.3762/bjoc.11.66

• stereocontrolled approach has been developed for the syntheses of tashiromine and epitashiromine alkaloids from cyclooctene β-amino acids. The synthetic concept is based on the azetidinone opening of a bicyclic β-lactam, followed by oxidative ring opening through ring C–C double bond and reductive ring-closure

• pyrrolizidine alkaloids [45]. Results and Discussion We describe here a novel access route for the synthesis of tashiromine and epitashiromine by starting from an unsaturated bicyclic β-lactam. The retrosynthetic concept of the synthesis is represented on Scheme 1 and was based on the lactam ring opening, in

• continuation followed by oxidative ring opening of the formed β-amino esters and by reductive ring closure as key steps. Bicyclic β-lactam (±)-1 [53][54] was first transformed by azetidinone opening to the corresponding amino ester hydrochloride (±)-2 [53][54], N-protection of which with benzyl chloroformate

Synthesis of highly functionalized β-aminocyclopentanecarboxylate stereoisomers by reductive ring opening reaction of isoxazolines

• Melinda Nonn,
• Loránd Kiss,
• Reijo Sillanpää and
• Ferenc Fülöp

Beilstein J. Org. Chem. 2012, 8, 100–106, doi:10.3762/bjoc.8.10

• Peramivir analogues has recently been investigated as potential antiviral agents [46][47]. Results and Discussion We recently reported a regio- and stereoselective procedure for the formation of a series of isoxazoline-fused cispentacin and transpentacin regio- and stereoisomers (2–6) from bicyclic β-lactam

Gold-catalyzed heterocyclizations in alkynyl- and allenyl-β-lactams

• Benito Alcaide and
• Pedro Almendros

Beilstein J. Org. Chem. 2011, 7, 622–630, doi:10.3762/bjoc.7.73

• palladium-based catalysts such as Pd(OAc)2, PdCl2, [Pd(PPh3)4], and [Pd2(dba)3]·CHCl3 failed to give the desired cyclized products, exposure of allenyl-β-lactams 1 to 5 mol % AuCl3 in CH2Cl2 produced the bicyclic β-lactam products, i.e., the Δ1-carbapenems 2 (Scheme 1). The desired products were produced in