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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)