Chapter 1 discusses the asymmetric synthesis of (3S)-hexahydropyridazine-3-carboxylic acid [(3S)-piperazic acid]. Two procedures were developed, firstly an electrophilic hydrazination of a chiral bromovaleryl carboximide enolate with di-tert-butylazodicarboxylate, followed by intramolecular SN2 displacement of the bromide by the resulting aza anion. Subsequent hydrolysis and acidolysis gave (3S)-piperazic acid in an enantiomeric excess greater than 96%. The second procedure was based on the formation of a titanium enolate from the chiral bromovaleryl carboximide at 0°C to form a hydrazine which was subsequently cyclised with the use of sodium hydride. Hydrolysis and acidolysis gave (3S)-piperazic acid in an enantiomeric excess of 78%. Chapter 2 is a concise review of the synthesis of natural cyclodepsipeptides between the years 1960 and 1994. Chapter 3 describes the evolution of a synthetic strategy for the cyclodepsipeptide portion of A83586C. A hexapeptide precursor has been prepared via a 3+2+1 fragment condensation
