The rational search for natural neolignans.

A rational method of search for natural neolignans of desired structures is outlined. This involves consultation of a collection of chemical profiles of plant families. The profiles are assembled considering the biosynthetic class (in the present case lignoids), subclass (neolignans), structural types (neolignan skeletal) and relative frequency of substitutional derivatives belonging to each type (known compounds). The method is of course applicable to any class of natural products. Its use in the case of neolignans is here selected as an example in view of the recently discovered antagonism towards PAF of kadsurenone, a representative of this subclass of phytochemicals. Application of the chemical profiles to phylogenetic studies is illustrated.