A sealed class in C++

I want a 'sealed' class in native C++ just like 'sealed' in C++/CLI and C# or 'final' in Java. I googled it then got following solution.

template<typename T>
class DeriveLock {
private:

DeriveLock() {}
~DeriveLock() {}
friend T;

};

class SealedClass : virtual public DeriveLock<SealedClass> {
};

You can found above sample code at Bjarne Stroustrup's article.