V. R. Hegde

Enantiospecific synthesis of β-lactams via cycloaddition

Enantiospecific synthesis of variously substituted cis-β-lactams can be achieved by the annelation of Schiff bases from optically active ketal aldehydes derived from D-threonine. Similar annelation of Schiff bases from the triphenylsilyl ether of D-threonine ester and cinnamaldehyde leads to cis-β-lactams with high diastereofacial selectivity.

Absolute configuration of α-substituted β-lactams from D-glyceraldehyde acetonide

3,4-Disubstituted-1-arylazetidin-2-ones can be prepared in an enantiospecific manner by the annelation of Schiff bases from optically active glyceraldehyde acetonide and their stereochemistry determined from n.m.r. studies on lactones prepared from these β-lactams by molecular rearrangement.

Studies on lactams. Part 74. An approach to the total synthesis of amino sugars viaβ-lactams

Convenient intermediates for mono- and di-amino sugars related to antibiotics can be prepared in a stereocontrolled fashion by the rearrangement of 3,4-disubstituted azetidin-2-ones which in turn can be synthesized by stereoselective annelation of certain imino compounds by substituted acetic acid derivatives.