Crystalline form of brassinosteroite (BR) analogies and methods of their preparation

Abstract

The invention proposes a new crystalline form of a brassinosteroid (BR) analog and a method for its preparation. The BR analog has the chemical formula C27H4SO7, the chemical name (20R,22R)-2p,3p,14a-14,20122,25-hexahedroxy-5pj8a,9a-cholestan-6-one and the structural formula . According to the invention, the new crystalline form with high biological activity is obtained by improving the recrystallization process of a naturally extracted BR analog. This new type of crystal could be applied in agriculture to promote plant growth.