This volume in the series summarizes the varied methods of the synthesis of heterocycles from azadienes with sections covering 1-azadienes, 2-azadienes, and 1,3-diazadienes. It covers the piperazine-2,5-diones and related lactim ethers - comprehensive review of these highly important intermediates for the preparation of a wide variety of natural products. The book explains how 1,2,4-Triazolo [1,5-a] pyrimidines are of particular importance in photography with other significant application in pharmaceuticals and agrochemicals. It also reviews tetramic acids, an importantgroup of natural products showing signifcant biological activity, as well as some chemistry.