Chemical name: 2, , 3, , 22r, 23r-tetrahydroxy-24r-methyl-b-homo-7-oxa-5, -cholestan-6-one Molecular formula: c29h50o6 Molecular weight: 494 Color: white powder Melting point: 256-258, Dosage form: 0.01%sp, 90%tc Usage: the same as that for 24-brassinolides. But the effect is much better than 24-brassinolides (around 2 to 5 times).