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Exhibit 31.1

                            CERTIFICATION PURSUANT TO
                                 SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

I, Jeffrey H. Buchalter, certify that:

1.        I have reviewed this Quarterly Report on Form 10-Q/A for the quarter
          ended December 31, 2004 of Enzon Pharmaceuticals, Inc. ("Enzon");

2.        Based on my knowledge, this report does not contain any untrue
          statement of a material fact or omit to state a material fact
          necessary to make the statements made, in light of the circumstances
          under which such statements were made, not misleading with respect to
          the period covered by this report;

3.        Based on my knowledge, the financial statements, and other financial
          information included in this report, fairly present in all material
          respects the financial condition, results of operations and cash flows
          of the registrant as of, and for, the periods presented in this
          report;

4.        The registrant's other certifying officer and I are responsible for
          establishing and maintaining disclosure controls and procedures (as
          defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
          registrant and have:

         (a)       Designed such disclosure controls and procedures, or caused
                   such disclosure controls and procedures to be designed under
                   our supervision, to ensure that material information relating
                   to the registrant, including its consolidated subsidiaries,
                   is made known to us by others within those entities,
                   particularly during the period in which this report is being
                   prepared;

          (b)      Evaluated the effectiveness of the registrant's disclosure
                   controls and procedures and presented in this report our
                   conclusions about the effectiveness of the disclosure
                   controls and procedures, as of the end of the period covered
                   by this report based on such evaluation; and

          (c)      Disclosed in this report any change in the registrant's
                   internal control over financial reporting that occurred
                   during the registrant's most recent fiscal quarter (the
                   registrant's fourth fiscal quarter in the case of an annual
                   report) that has materially affected, or is reasonably likely
                   to materially affect, the registrant's internal control over
                   financial reporting; and

5.        The registrant's other certifying officer and I have disclosed, based
          on our most recent evaluation of internal control over financial
          reporting, to the registrant's auditors and the Audit Committee of the
          registrant's board of directors (or persons performing the equivalent
          functions):

          (a)      All significant deficiencies and material weaknesses in the
                   design or operation of internal control over financial
                   reporting which are reasonably likely to adversely affect the
                   registrant's ability to record, process, summarize and report
                   financial information; and

          (b)      Any fraud, whether or not material, that involves management
                   or other employees who have a significant role in the
                   registrant's internal control over financial reporting.

September 28, 2005

                                           By: /s/Jeffrey H. Buchalter
                                               -----------------------
                                               Jeffrey H. Buchalter
                                               Chairman, President and
                                               Chief Executive Officer
                                               (Principal Executive Officer)