Complex sentence: In 1834, the company bought all the Missouri River interests of the Astor Fur company and it was reorganized in 1838 as Pierre Chouteau, Jr., and Company until it dissolved in 1864.
Split into simpler sentences: In 1834, the company bought all the Missouri River interests of the Astor Fur company. It was reorganized in 1838 as Pierre Chouteau, Jr., and Company until it dissolved in 1864.