Qualcomm, the American chip maker, spent two years hammering out a $44 billion deal to acquire a Dutch semiconductor manufacturer. Then, as the trade war with the United States erupted, Chinese regulators effectively killed it.

Now China is looking for new ways to retaliate in the intensifying trade drama — and experts warn that some corporate deals with American buyers could be in jeopardy.

A number of global deals involving American companies are under review by Chinese market regulators. Among the biggest is Walt Disney Company’s $71 billion acquisition of 21st Century Fox, which has an Oct. 19 deadline. United Technologies — owner of Pratt & Whitney, the jet engine maker, and other industrial businesses — is waiting to close a $30 billion purchase of Rockwell Collins, the aerospace parts maker.

China’s antitrust regulators disclose little about their deliberations. But some companies worry that this opacity could provide cover for retaliation in response to tariffs that the United States has placed on Chinese goods — and wonder if long-negotiated deals could become collateral damage in the trade war.