The fifth volume of Advancea in Heterocyclic chemistry surveys the
chemistry of four well-defined groups of compounds : pyrrolizidines
(N. K. Kochetkov and A. M. Likhosherstov), aromatic quinolizines
(B. S. Thyagarajan), 1,2,4-thiadiazoles (F. Kurzer), and the aminochrome
pigments (R. A. Heacock).
The other two chapters deal with the application of molecular
orbital theory to heterocyclic chemistry. The groups surveyed are (a)
sulfur heterocycles and (b) azines. The chapters, which are authored
by R. Zahradnik and J. Koutecky, discuss the relevance of theoretical
calculation to reactivity, electronic structure, and other physicochemical
properties of the compounds. The new techniques of theoretical
chemistry have been applied with great success to carbocyclic
compounds ; their significance in heterocyclic chemistry will surely
increase.