(-)-(3S)-3-(Tosylamino)butano-4-lactone, a Versatile Chiral Synthon for the Enantioselective Synthesis of Different Types of Polyamine Macrocycles: Determination of the Absolute Configuration of (-)-(R)-Budmunchiamine A.

(−)-(3S)-3-(Tosylamino)butano-4-lactone (1) and its derivative ethyl (−)-(3S)-4-iodo-3-(tosylamino)butanoate (2) are presented as easily accessible chiral building blocks for the construction of a range of different macrolactam frameworks important for the synthesis of naturally occurring polyamine alkaloids as well as for establishing a substance library of such compounds, including S-containing derivatives for biological tests. In addition to that, the absolute configuration of the spermine alkaloid (−)-(R)-budmunchiamine A (3) from Albizia amara was determined by total synthesis according to the new methodology.