Crystal structure of fusicoccin A p-iodobenzenesulphonate

Abstract

The crystal and molecular structure of the p-iodobenzenesulphonate of fusicoccin A (C42H59IO14S) has been determined by three-dimensional X-ray analysis. The crystals are orthorhombic, space group P212121, with Z= 4 in a unit cell of dimensions: a= 10·32, b= 12·89, c= 35·14 A. The structure was solved by the heavy-atom technique and refined to a final R of 0·116, using 1706 observed reflections.Fusicoccin A, a phytotoxic metabolite of Fusicoccum amygdali, is a glycoside in which the sugar is D-glucose acetylated at C-3′ and etherified by 1,1-dimethylallyl alcohol at C-6′, and the aglycone is a tricyclic system formed by the fusion of one eight and two five membered rings. The absolute configuration is also given.