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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 of Enzon
      Pharmaceuticals, Inc. ("Enzon");

2.    Based on my knowledge, this quarterly 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 quarterly 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 we 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 quarterly report is being
                  prepared;

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

            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 to the audit committee of 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 reasonable 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 27, 2005                         By: /s/Jeffrey H. Buchalter
                                               --------------------------------
                                               Jeffrey H. Buchalter
                                               Chairman, President and
                                               Chief Executive Officer
                                               (Principal Executive Officer)