The Gannett Co. Inc. has agreed to acquire KRON-TV in San Francisco from the Chronicle Broadcasting Co. in return for KOCO-TV in Oklahoma City and $100 million. In its announcement today, Gannett said it would divest itself of its Oakland Tribune-East Bay Today newspapers.

Gannett said it must transfer ownership of KOCO-TV because the acquisition of KRON, in one of the nation's top five television markets, would give Gannett more than seven television stations. Federal regulations limit the number of television stations a company can own to seven.

The purchase of KRON also forces the company to divest itself of the Oakland Tribune-East Bay Today papers because federal regulations do not permit a company to own a newspaper and broadcast outlet in the same geographical market.

"We will seek to put these newspapers in the hands of responsible new owners, preferably local . . . .," said Allen Neuharth, Gannett's chairman and president.

Gannett, publisher of the new national newspaper USA Today, said it expected to obtain government approval of the television license transfers by early next year.

In another newspaper development in New York, The Daily News and its 11 labor unions completed tentative agreements to assure that the newspaper is published continuously through March, 1987, the newspaper said.

The agreement to extend contracts three years beyond the current pact was announced three hours after a "final deadline" the newspaper's management set for midnight Friday. Details of the agreement were withheld until the contracts can be prepared for a meeting scheduled for Tuesday.