The invention relates to compounds shown as a general formula and preparation thereof and application thereof to pesticides. The invention provides a novel structure resisting tobacco mosaic viruses,which has the characteristics of contribution to industrialization, simple synthesis and the like. Racemic gossypol D-amino acid Schiff base and Schiff base derivatives of levorotatory or dextrorotatory gossypol have very good activity of resisting the tobacco mosaic viruses (protection, treatment and passivation). In the formula, the meaning of R is described in the specification.