International Chemical Investors Group announced Wednesday evening that it plans to acquire Roche Colorado Corp., which includes Roche’s pharmaceutical production facility in Boulder. The acquisition price was not disclosed. The Roche Group, headquartered in Switzerland, employs approximately 265 workers in Boulder who develop and manufacture drug compounds. Frankfurt, Germany-based ICIG intends to operate the Boulder site, which will be renamed Corden Pharma Colorado Inc., as part of its pharmaceutical business within the Corden Pharma organization. The chemical plant in Boulder was founded in 1946 as Arapahoe Chemicals Inc. by two brothers, Tom Waugh and Dick Waugh. The company was purchased by Syntex Corp. in 1965, and Roche Holdings Inc. purchased Syntex in 1994.