An underwriter, placement agent, initial purchaser, or sponsor, or any affiliate or subsidiary of any such entity, of an asset-backed security (as such term is defined in section 78c of this title, which for the purposes of this section shall include a synthetic asset-backed security), shall not, at any time for a period ending on the date that is one year after the date of the first closing of the sale of the asset-backed security, engage in any transaction that would involve or result in any material conflict of interest with respect to any investor in a transaction arising out of such activity.