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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 annual report on Form 10-K/A 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)


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