More than twenty dibenzocyclooctadlene lignan derivertives have been prepared from natural compounds schisantherin A,schisandrol A,B and kadsuranin B. Most of them were tested for the inhibition of microtubule assembly in vitro.Among them,the four-ring compounds B6,B15,derived from schisandrol A under Ritter condition and schisantherin A with SOCl2/Py condition, were reported at the first time and fully identified. The structure of decomposed compounds B19,B22 from the oxidation of B11 and B15 (i.e. the oxidation of α, β—, α', β'— unsaturated cyclohex ketone with β-OH) were deduced initially .Also, the Claisen rearrangement used in the preparation of the derivertives was discussed.
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