Sheldon and Alexandra Weinbaum bought a condo at 96 Main St. in Brooklyn from Nirmala Charan and Brian Riley for $1.45 million on Sept. 24.

Unit #5L is part of the The Clocktower condo development, which is located in the DUMBO neighborhood.

Mr. Weinbaum is a professor in the mechanical engineering department of the City University of New York.

He received his M.S. in applied physics and his Ph.D. in engineering from Harvard University. He has a B.A.E. from Rensselaer Polytechnic Institute.

Ms. Weinbaum is vice president and director of the center for school and community service at the Academy for Educational Development in Washington, D.C.

She previously was a program director at the City University of New York and a sex equity coordinator for NYC's Community Districts 2 and 3.

She has a Ph.D. in history from Columbia University.

Charan is a managing director of Carreden Group Inc., a specialty investment banking firm with offices in New York and Moraga, Calif.

She formerly worked at D'Accord Financial Services Inc. and at its successor company, Dresdner Kleinwort Wasserstein.

She received a B.A. in journalism from New York University.

According to BlockShopper.com, there were 4,709 sales in Brooklyn in 2008, with a median sales price of $448,000.