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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 amended Quarterly Report on Form 10-Q/A for the
     quarter ended September 30, 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.   I am 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; 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

         (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.   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)