For example, corporations are strictly creatures of law; they exist IF and Only If, and in the form that the law allows, at the pleasure of the government.
So, rewrite the enabling laws to state specifically and explicitly that corporations have affirmative responsibilities not only to the shareholders, but also to their workers, the community, the nation, and the environment, etc.
That alone immediately gives cover to any executive or board taking action that benefits those entities and perhaps not so much the shareholders. So they have a defense against shareholder suits that seek to force action or compensation away from corporate responsibility. Plus, there would also be a cause of action from the other parties for failure to take care of their interests. Obviously, this could go too far in either direction, so it must be carefully written, but this is the general idea.
There are many other ways, but that's the idea, don't rely solely on regulation.
Those are interested ideas. But it begs the question: How to enforce compliance without regulation?