Editorial [Hot Topic: Heterocyclic Chemistry (Guest Editor: Jan Bergman)]

Nitrile ylides are of considerable interest both from a theoretical and a synthetic viewpoint. Both aspects are discussed in the first account contributed by Prof. S. Vazquez and his co-workers from the University of Barcelona, Spain. Hydrazonates can be converted to a wide variety of heterocycles as demonstrated by Prof. Shawali and Prof. Sherif from the University of Cairo, Egypt. Unnatural α-amino acids is an active field where heterocyclic molecules are of considerable importance both during the synthetic build-up and as targets. The recent advances in the field have now been reviewed by Drs A. Perdih and M. Sollner form the University of Ljubljana, Slovenia. Butylphthalides constitutes natural products and synthetic analogues with diverse biological effects. The progress in the area has now been scrutinized by Dr Li and Dr Xiong from the Sichuan College of Education, China.