Complex sentence: In the late 1980s, mismanagement led to the downfall of Main and it was bought by Parsons Corporation of Pasadena, California, which changed its name to Parsons Main, Inc. in January 1992.
Split into simpler sentences: In the late 1980s, mismanagement led to the downfall of Main and it was bought by Parsons Corporation of Pasadena, California. Chas T. Main, Inc. changed its name to Parsons Main, Inc. in January 1992.