SYNTHETIC STUDIES TOWARDS THE NATURAL PRODUCT LEOPOLIC ACID A

The need to develop new fungicides remains a major driving force as fungal plant pathogens continue to develop resistance against existing fungicides at great speed, and also because new disease situations continually arise. Natural products have been and still are large reservoirs of new biologically active substances for crop protection development, by serving as lead structures for the discovery of active molecules, often featuring novel and unique modes of action. Many pesticides have been developed from naturally occurring lead compounds. An outstanding example is the class of fungicides that has been generated from strobilurins, antifungal metabolites of myxobacteria. Aim of the PhD work was the study of new naturally derived antifungal compounds and the development of synthetic sequences which might, in principle, have value in the preparation of the natural products themselves as well as in synthesizing various analogues. Among a number of possible candidates we have selected a natural products, Leopolic acid A as synthetic target, as it has been reported to be endowed with antifungal activity. During the PhD period the synthesis of this natural product and structurally related analogues has been carried out. Antifungal and antimicrobial activities of the compounds have been evaluated, and preliminary SAR have emerged.