Before any national bank shall be permitted to purchase stock in any corporation described in , the said corporation shall enter into an agreement or undertaking with the Board of Governors of the Federal Reserve System to restrict its operations or conduct its business in such manner or under such limitations and restrictions as the said board may prescribe for the place or places wherein such business is to be conducted. If at any time the Board of Governors of the Federal Reserve System shall ascertain that the regulations prescribed by it are not being complied with, said board is authorized and empowered to institute an investigation of the matter and to send for persons and papers, subpoena witnesses, and administer oaths in order to satisfy itself as to the actual nature of the transactions referred to. Should such investigation result in establishing the failure of the corporation in question, or of the national bank or banks which may be stockholders therein, to comply with the regulations laid down by the said Board of Governors of the Federal Reserve System, such national banks may be required to dispose of stock holdings in the said corporation upon reasonable notice.section 601 of this title