Brentwood Associates said it heads a group...

Brentwood Associates said it heads a group that agreed to buy two oil field equipment firms from Minstar Inc., the company headed by Minneapolis investor Irwin L. Jacobs. Brentwood, a Los Angeles investment firm, said its partners in the $150-million leveraged buyout include management of one of the firms, Tuboscope Inc. of Houston. The other firm is Cherco Compressors Inc., Longview, Tex. They had combined sales last year of $143 million. Jacobs had said he would sell the energy units as part of a plan to take Minstar private. Brentwood Associates general partner Timothy M. Pennington said it is also trying to buy Ideal School Supply Corp., Oak Lawn, Ill.