SAN JOSE — A failed loan has scuttled a years-long effort to transform a San Jose office hub into a biotech center that now has a new owner after a foreclosure of the property.

A big north San Jose tech park known as BioSquare Silicon Valley, a big tech park in north San Jose, has been seized through a speedy foreclosure by veteran real estate firm South Bay Development, documents filed on March 20 with the Santa Clara County Recorder’s Office show.

Interior areas of BioSquare Silicon Valley, a biotech and tech incubator hub at 2680 Zanker Road in San Jose. (George Avalos/Bay Area News Group)Interior areas of BioSquare Silicon Valley, a biotech and tech incubator hub at 2680 Zanker Road in San Jose. (George Avalos/Bay Area News Group)

Unpaid real estate debts totaling $158.7 million loomed over the BioSquare Silicon Valley tech hub at the time of the transaction, which was accomplished through a deed in lieu of foreclosure, according to the county filing.

It wasn’t disclosed how much an affiliate of Los Gatos-based South Bay Development paid for the campus, which totals 456,000 square feet, according to a marketing brochure prepared by JLL, a commercial real estate firm.

The tech hub has addresses of 2860 Zanker Road and 2585 Junction Ave., the public documents show.

A group headed up by real estate executive Tony Gonzalez was attempting in recent years to attract life sciences tenants to the office park, which was also being revamped as a tech incubator and biotech hub.

Despite these efforts, this news organization’s direct observations of the site on numerous occasions, including some recently, showed that many of the workspaces at the property remained empty over the years.

BioCube San Jose North was designed to be flexible enough to accommodate companies that need small spaces to conduct cutting-edge research, along with spaces to handle the same companies, or other firms, that are larger and in a growth spurt.