A Durst building there would complete a string of three from 42d to 45th Street.

If it cannot be placed there, he said, it will go to another Durst building.

Mr. Dimson said he expects the Durst building to stimulate interest in an environmentally better workplace.

The proposed Durst building may have special appeal to state and city officials eager to keep financial-industry companies in the city.

An updated model, which can run backwards, was installed one block away on a Durst building at 1133 Avenue of the Americas (Sixth Avenue).

The city evacuated the Durst building and cited the Maidmans for a series of violations.

Now the association is focusing on sites in Manhattan, including the new Durst building and the Gansevoort area.

They had gradually let occupancy decline, in some cases relocating tenants to other Durst buildings in the midtown area, including the building at 234 East 46th Street.

The shuttle between Times Square and Grand Central Terminal runs under a corner of the Durst building at 42d Street and Broadway.

It is perched these days on the side of a Durst building at 1133 Avenue of the Americas, near 44th Street.