Dropped into the Senate tax-cut bill late Tuesday night was an obscure provision aimed at preventing Texas International Airlines from taking over Continental Airlines.

The provision, which does not name either airline but is written in a way that can apply only to this situation, was introduced by Sen. Dennis DeConcini (D-Ariz.), whose brother-in-law is a Continental pilot.

It has now become a hotly disputed item in the conference on the bill. It was not in the House version and can still be shot down.

Some big names have been hired to help in the fray.

In Texas International's hangar, hired in the 48 hours after the amendment was slipped into the Senate bill, are former House member James Corman (D-Calif.), now with the law firm headed by Democratic Natinal Committee Chairman Charles Manatt, and Robert S. Strauss, former ambassador and former Democratic national chairman.

On Continental's flight line are Stuart E. Eizenstat, former president Carter's assistant for domestic affairs and policy, Simon Lazarus, former associate director of the White House domestic policy staff,and Susan Williams, former assistant secretary of transportation.

To fend off Texas International, Continental has come up with a plan to issue its employes enought stock to give them control. Continental would issue 15.4 million new shares, more than double the amount currently outstanding, to an employe stock ownership plan in order to dilute the $100 million 48.5 percent share Texas International now holds.

Continental's plan ran into a snag when California's commissioner of corporations ruled it "unfair and misleading" and ordered it be put to a vote by the company's shareholders and employes. The New York Stock Exchange had also ruled Continental's stock would be delisted if it went ahead with the employe plan without a shareholder vote.

The DConcini amendment seeks to circumvent these objections by waiving a law specifically leaving to the states the job of regulating the issuance of securities to employes under employe benefit plans.