Section 1. In the administration of any trust which is a ''private foundation'', as defined in section 509 of the Internal Revenue Code of 1954, or a ''split-interest trust'' as defined in section 4947(a)(2) of said Code, the following acts shall be prohibited:
(a) engaging in any act of ''self-dealing'' (as defined in section 4941(d) of said Code, which would give rise to any liability for the tax imposed by section 4941(a) of said Code;
(b) retaining any ''excess business holdings'' (as defined in section 4943(c) of said Code) which would give rise to any liability for the tax imposed by section 4943(a) of said Code;
(c) making any investments which would jeopardize the carrying out of any of the exempt purposes of the trust, within the meaning of section 4944 of said Code, so as to give rise to any liability for the tax imposed by section 4944(a) of said Code; and
(d) making any ''taxable expenditures'' (as defined in section 4945(d) of said Code) which would give rise to any liability for the tax imposed by section 4945(a) of said Code; provided, however, that this section shall not apply either to those split-interest trusts or to amounts thereof which are not subject to the prohibitions applicable to private foundations by reason of the provisions of section 4947 of said Code.