Chiral Β-lactam Research Articles

An aziridine route to chiral β-lactams a novel entry to (+)-thienamycin

Enantiomerically pure 2,3- epoxy alcohols are transformed readily and stereospecifically to the corresponding aziridines, regioselective ring-opening of which allows subsequent conversion to chiral β-lactams suitable for elaboration to the title antibiotic.

Enantioselective aldol reaction of chiral acyl thiazolidine thione derived boron enolates

The compatability of an acyl thiazolidine thione as a chiral auxillary in boron enolate chemistry has been demonstrated by an enantioselective aldol condensation. The aldol products provide direct access to chiral β-lactams.

OBTENTION D’UN α-AMINO ALDEHYDE OPTIQUEMENT ACTIP EN SERIE β-LACTAME

Abstract Oxidation of a suitable protected L-aspartic acid derived azetidinone gives rise to a chiral β-lactam carboxaldehyde without significant racemization.

The use of β-lactams in the synthesis of spermine and spermidine alkaloids : Total synthesis of homaline

The optically active plant product homaline ( 6) has been synthesized in a convergent sequence starting with β-phenyl-β-alanine and putrescine ( 14) The key transformation in this sequence is the ring expansion by transamidation of a functionalized chiral β-lactam precursor

Effective method for the asymmetric synthesis of bis-β-lactams by the cycloaddition of azidoketen to benzylideneamines bearing a chiral β-lactam backbone

Extremely high stereoselectivity was observed in the asymmetric cycloaddition of azidoketen to 1-[(S)-1-t-butoxycarbonylethyl]-3-benzylideneamino-4-phenyl-azetidin-2-ones, which gave rise to the formation of optically pure bis-β-lactams.