The only AutoCAD product that syncs with ISM is Revit. Frameworks does not sync with ISM either. For a list of the ISM enabled applications, please visit our wiki: communities.bentley.com/.../integrated-structural-modeling-home.aspx
Meanwhile, have you tried CIS/2 format? This can be exported directly from STAAD, and maybe imported into Frameworks.
The only other option I can think of would be to generate an IFC file form the .ism.dgn repository and import the IFC file into Frameworks, but that would not allow any round tripping and probably some reduced fidelity.