NEW YORK (Reuters) - The head of a New York-based metallurgy company was sentenced to four years and nine months in prison on Thursday for conspiring to illegally export missile-grade metallic powder to Iran.

Erdal Kuyumcu, 45, was sentenced by U.S. District Judge Dora Irizarry in Brooklyn after pleading guilty in June 2016 to conspiring to violate the International Emergency Economic Powers Act, court records show.

“We are obviously very disappointed in the court’s sentence today, and will be exploring the available options,” said Kuyumcu’s attorney, Patrick Mullin, who had sought a sentence of probation.

Prosecutors said Kuyumcu, the chief executive of Global Metallurgy LLC, conspired to obtain more than 1,000 pounds (450 kg) of cobalt-nickel metallic powder, which can be used in aerospace, missile production and nuclear applications, for export to Iran.

The U.S. government closely regulates the powder to combat nuclear proliferation and protect national security, and exporting it requires a license from the Department of the Treasury.

According to prosecutors, Kuyumcu, a naturalized U.S. citizen of Turkish descent, and a co-conspirator hid the final destination of their powder by arranging for it to be shipped through Turkey, before being sent on to Iran.

The case is U.S. v. Kuyumcu, U.S. District Court, Eastern District of New York, No. 16-cr-00308.