Synthesis, crystal structure and NMR investigation of a new type of cyclic steroidal dimer based on brassinosteroids

A new type of cyclic steroidal dimer based on brassinosteroids has been synthesized via the reaction of 24-epibrassinolide with 1,4-phenylenediboronic acid and structurally characterized by single-crystal X-ray diffraction and 2D NMR analysis. The crystal structure of the dimer was found to contain rather large solvent accessible voids.