Stock futures were mixed Wednesday as Brent crude futures briefly hit
$100 a barrel for the first time since July.
Oil prices extended gains amid fears of prolonged supply disruptions after the conflict continued to escalate between the U.S. and Iran, with the U.S. Central Command saying it destroyed five Iranian oil vessels.
"Markets seem to be treading water this week as increases in energy prices dampen risk appetite," Deutsche Bank said.
"With inflationary pressures still mounting, that kept the pressure on other asset classes too," it added. Inflation is in focus right now because the consumer-price index report for August is due out on Friday.
