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                                                                    EXHIBIT 10.1

                              EMPLOYMENT AGREEMENT


         EMPLOYMENT AGREEMENT (this "Agreement") dated as of December 22, 2004
(the "Effective Date" or "Commencement Date"), between Enzon Pharmaceuticals,
Inc. (the "Company"), a Delaware corporation with offices in Bridgewater, New
Jersey, and Jeffrey H. Buchalter (the "Executive"), a resident of San Antonio,
Texas.

         WHEREAS, the Company is a biopharmaceutical company engaged in
developing advanced therapeutics for life threatening diseases; and

         WHEREAS, Executive has extensive experience as an executive of a
pharmaceutical company; and

         WHEREAS, the Company wishes to employ the Executive to render services
for the Company on the terms and conditions set forth in this Agreement, and the
Executive wishes to be retained and employed by the Company on such terms and
conditions;

         NOW, THEREFORE, in consideration of the premises, the mutual agreements
set forth below and other good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties agree as follows:

         1. Employment. The Company hereby employs the Executive, and the
Executive accepts such employment and agrees to perform services for the
Company, for the period and upon the other terms and conditions set forth in
this Agreement.

         2. Term. The term of the Executive's employment hereunder shall
commence on the Effective Date, and unless terminated at an earlier date in
accordance with Section 9 hereof, shall extend through such date, not earlier
than December 31, 2009, which is twelve (12) months following the date on which
either party hereto receives written notice (a "notice of non-renewal") from the
other party that such other party does not wish for the term hereof to continue
beyond such twelve (12) month period (the "Term"). Subject to possible earlier
termination in accordance with Section 9 hereof, unless and until a notice of
non-renewal is given by a party, the Term shall always have at least twelve (12)
months remaining, and all of the provisions of this Agreement shall continue in
full force and effect during such period.

         3. Position and Duties.

         (a) Service with Company. During the term of the Executive's
employment, the Executive shall serve in the positions of President and Chief
Executive Officer of the Company and the chairman of the Company's Board of
Directors (the "Board") (the "Chairman of the Board"), and Executive shall have
the authority, duties and responsibilities associated with those positions,
including, without limitation, the authority and duty generally to supervise and
direct the business of the Company, subject to the control and direction of the
Board and of any duly authorized Committee of the Board.

         (b) Performance of Duties.

                  (i) Subject to the provisions hereof, the Executive agrees to
         serve the Company faithfully and to the best of his ability and to
         devote his full time, attention and efforts to the business and affairs
         of the Company during his employment by the Company.
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                  (ii) Executive has provided the Company with: 1) a draft of a
         Consulting Agreement between Executive and Genzyme Corporation
         ("Genzyme") (such draft substantially in the form as previously sent to
         the Company being the "Consulting Agreement"); and 2) the Employment
         Agreement, dated as of January 1, 2002, agreed to by Executive and
         Executive's former employer (the "Employee Agreement") which, to the
         best of Executive's knowledge, are the only agreements which could
         arguably restrict or interfere with his employment activities
         subsequent to the termination of his employment with such former
         employer. Company agrees that the execution by Executive of and the
         performance by Executive of his obligations under the Consulting
         Agreement shall not constitute a breach of this Agreement, and Company
         specifically authorizes Executive to fulfill the terms of the
         Consulting Agreement. Further, in the event that Genzyme elects not to
         execute the Consulting Agreement or in the event the Consulting
         Agreement is terminated (other than termination by or at the behest of
         the Executive or as a result of Executive's refusal to perform the
         services required of him under the Consulting Agreement, provided such
         refusal to perform is not related to Executive's employment pursuant to
         this Agreement) then the Company shall pay to Executive an amount which
         is equal to 50% of the payments which would have been payable to
         Executive under the Consulting Agreement and were not paid by Genzyme
         (such payments by the Company being referred to herein as "Consulting
         Agreement Payments"). Any Consulting Agreement Payments made by the
         Company to Executive shall be made at the same time (the "Consulting
         Agreement Payment Date") and subject to the same conditions as the
         corresponding payments which would have been made to Executive under
         the Consulting Agreement. In no event shall the Consulting Agreement
         Payments made by the Company exceed $750,000. The Company and the
         Executive agree that any Consulting Agreement Payments required to be
         made by the Company pursuant to this 3(b)(ii) shall be in the form of
         shares of the Company's common stock (the "Common Stock") issued
         pursuant to the Company's 2001 Incentive Stock Plan, as amended (the
         "Stock Plan") and the number of shares of Common Stock to be issued to
         the Executive as a Consulting Agreement Payment shall be determined by
         dividing the amount of the Consulting Agreement Payment by the last
         reported sale price of a share of Common Stock as reported by the
         Nasdaq Stock Market on any such Consulting Agreement Payment Date or,
         if the Nasdaq Stock Market is not open on such Consulting Agreement
         Payment Date, on the day next preceding such Consulting Agreement
         Payment Date on which the Nasdaq Stock Market is open. Any tranche of
         shares of Common Stock issued to the Executive pursuant to this Section
         3(b)(ii) shall vest in three equal amounts on each of the first three
         anniversary dates of the Consulting Agreement Payment Date on which
         they were issued. Executive shall pay to the Company an amount equal to
         the aggregate par value of any such Common Stock issued pursuant to
         this Section 3(b)(ii) at the time of issuance. The grant of such Common
         Stock shall be represented by, and subject to, the terms of a
         restricted stock agreement substantially similar to the agreement
         annexed hereto as Exhibit B. If the number of shares of Common Stock
         available for issuance under the Stock Plan on any Consulting Agreement
         Payment Date is not sufficient to enable the Company to meet its
         obligations under this Paragraph, then the Company shall cover any
         deficiency in the required payment amount by making an additional
         payment in the form of cash or, at the Company's sole option, shares of
         Common Stock issued outside of the Stock Plan. Prior to the issuance of
         any Common Stock pursuant to this Section 3(b)(ii) to the Executive,
         the Company shall cause such issuance to be registered under the
         Securities Act of 1933, as amended (the "1933 Act"), such that
         Executive will be able to sell such common stock without complying with
         the holding period required under Rule 144 promulgated under the 1933
         Act.

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                  (iii) Executive agrees that he will not use on behalf, or for
         the benefit, of the Company or disclose to the Company any confidential
         information of or concerning his former employer or, to the extent
         prohibited by the Consulting Agreement, Genzyme. It is the Company's
         intention that Executive not breach any confidentiality agreement he
         may have with his former employer or Genzyme. Based on his knowledge of
         his former employer's business and confidential information and the
         information concerning the Company's business heretofore provided to
         Executive by the Company or publicly available, to the best of
         Executive's knowledge, his entering into and performing this Agreement
         will not constitute a breach of the Employee Agreement or the
         Consulting Agreement as same may be executed by Executive and Genzyme
         or any other obligation of the Executive. Executive will not render or
         perform services for any other corporation, firm, entity or person
         which are inconsistent with the provisions of this Agreement other than
         pursuant to the terms of the Consulting Agreement.

                  (iv) While he remains employed by the Company, the Executive
         may participate in reasonable charitable activities and personal
         investment activities so long as such activities do not conflict or
         interfere with the performance of his obligations under this Agreement.
         Subject to the prior approval of the Board, which will not be
         unreasonably withheld, subsequent to the first anniversary of the
         Commencement Date Executive may join and serve on the board of
         directors of one other company, provided that such other company is not
         a competitor of the Company and such service would not interfere with
         Executive's obligations to the Company hereunder or involve or
         potentially involve a conflict of interest, as determined by the Board.

         4. Compensation.

         (a) Base Salary. The Company shall pay to the Executive, less
applicable deductions and withholdings, base salary (the "Base Salary") at an
annual rate of Five Hundred Fifty Thousand Dollars ($550,000) per year, which
Base Salary shall be paid in accordance with the Company's normal payroll
procedures and policies for its senior management. The compensation payable to
Executive during each fiscal year of the Company beginning after the
Commencement Date shall be established by the Board or the Compensation
Committee thereof following an annual performance review, but in no event shall
the annual rate of Base Salary for any successive year of the Term be less than
the highest annual rate of Base Salary in effect during the previous year of the
Term.

         (b) Annual Bonus. Commencing with the fiscal year ending June 30, 2005,
Executive shall be entitled to participate in the Company's bonus plan for
management and any successor bonus plan covering management (the "Bonus Plan").
Under the Bonus Plan, the Executive shall be eligible to receive a
performance-based cash bonus for each year of employment (commencing July 1,
2004) in an amount, and based on individual and/or corporate objectives, targets
and factors (and evaluation as to the extent of achievement thereof), to be
established and determined by the Board in its discretion following consultation
between the Board and Executive prior to, or within sixty (60) days after the
commencement of, each fiscal year (the "Performance Criteria"). Under the Bonus
Plan for Executive, (i) the minimum cash bonus shall be zero (0), (ii) the
target cash bonus shall equal 100% of the Base Salary (the "Target Bonus"), and
(iii) the maximum cash bonus shall equal 200% of Base Salary. Notwithstanding
the foregoing, and subject to the provisions of Section 10 hereof Executive
shall be entitled to receive a guaranteed minimum cash bonus in the amount of
Four Hundred Twelve Thousand Five Hundred Dollars ($412,500) for the fiscal year
ending June 30, 2005, which bonus shall be payable in July 2005 (the "2005
Bonus"). Within sixty (60) days after the end of each fiscal year, the Board,
based upon its evaluation as to the extent of Executive's achievement of the
Performance Criteria, shall award Executive his performance-based cash bonus, if
any, hereinafter referred to as the "Earned Bonus."

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         (c) Participation in Benefit Plans; Indemnification. While he is
employed by the Company, Executive shall also be eligible to participate in any
incentive and employee benefit plans or programs which may be offered by the
Company to the extent that Executive meets the requirements for each individual
plan and in all other plans in which Company executives participate. The Company
provides no assurance as to the adoption or continuance of any particular
employee benefit plan or program, and Executive's participation in any such plan
or program shall be subject to the provisions, rules and regulations applicable
thereto. To the extent the Company's group life insurance plan available for
Executive provides for a death benefit of less than $3 million and the Company's
long-term disability insurance policy provides for an annual disability benefit
to Executive of less than $500,000, the Company shall reimburse Executive for an
aggregate of up to $15,000 per year to cover Executive's cost of acquiring
supplemental group term life insurance and supplemental long-term disability
insurance to provide benefits that cover the foregoing deficiencies in coverage
under the Company's policies. The Company shall indemnify Executive and hold him
harmless from and against any claim, liability and expense (including, without
limitation, reasonable attorney fees) made against or incurred by him in
connection with his employment by the Company or his membership on the Board, in
a manner and to an extent that is not less favorable to the Executive as the
indemnification protection that is afforded by the Company to any other senior
officer or director and that is consistent with industry custom and standards.

         (d) Expenses.

                  (i) The Company will pay or reimburse Executive for all
         reasonable and necessary out-of-pocket expenses incurred by him in the
         performance of his duties under this Agreement, subject to the
         Company's normal policies for expense verification. The Company shall
         also reimburse Employee for the reasonable and necessary costs of
         relocating his household goods from San Antonio and other reasonable
         and necessary moving and interim housing expenses incurred in
         connection with the move of Employee and his family from San Antonio,
         Texas to the New Jersey area. Such reasonable and necessary moving and
         interim housing expenses shall include, but not be limited to (1)
         realtor commissions and customary closing costs in connection with the
         sale of his home in Texas and interim loan closing costs and permanent
         loan closing costs relating to the acquisition of his home in the New
         Jersey area, (2) interest payments on the mortgage loan relating to his
         home in Texas until such time as his home in Texas shall have been sold
         and (3) extra or redundant costs (other than the principal payments on
         his mortgage loan relating to his home in Texas) associated with, or
         incurred in connection with, the continued ownership of his home in
         Texas pending its sale. In addition, the Company shall provide an
         additional payment to Executive such that after taking into account any
         taxes on such payment, Executive shall retain a sufficient amount equal
         to any income tax liability incurred by Executive in connection with
         the foregoing payments and reimbursements under this subparagraph
         (d)(i).

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                  (ii) The Company will also bear the cost of a corporate
         country club membership, at Fiddler's Elbow Country Club, for use by
         Executive during the Term. Subject to the accuracy of the
         representations by Executive in Section 3(b) hereof, the Company shall
         reimburse Executive for all reasonable costs incurred by Executive in
         defending any action by Executive's prior employer or Genzyme which
         seeks to prevent or restrict Executive from performing his duties and
         obligations to the Company hereunder.

         (e) Stock Options.

                  (i) Subject to Executive commencing his employment hereunder
         as the Company's President and Chief Executive Officer on the
         Commencement Date, Executive shall be granted an option to purchase
         725,000 shares of Common Stock (the "Option") pursuant to the Stock
         Plan and the form of Non-Qualified Stock Option Agreement attached
         hereto as Exhibit A (the "Option Agreement") with an exercise price per
         share equal to the last reported sale price of a share of Common Stock
         as reported by the Nasdaq Stock Market on the Commencement Date or, if
         the Nasdaq Stock Market is not open on the Commencement Date, on the
         day next preceding the Commencement Date on which the Nasdaq Stock
         Market is open. The Option shall vest and be exercisable as to 225,000
         shares on the Commencement Date, and as to an additional 125,000 shares
         on each of the first four anniversaries of the Commencement Date. In
         addition, at the discretion of the Board of Directors (or its
         applicable committee), Executive shall be entitled to receive further
         grants of stock options, subject to the terms of the Stock Plan.

                  (ii) The Option shall immediately and fully vest and become
         exercisable when the last reported sale price of a share of the Common
         Stock is at least one hundred dollars ($100.00) as reported on the
         Nasdaq Stock Market for at least twenty (20) consecutive trading days,
         provided that, except as otherwise provided in Section 10 hereof,
         Executive is then employed by the Company. Except as otherwise provided
         in Section 10 hereof, once the Option becomes exercisable it shall
         remain exercisable until 5:00 p.m. New York City time on the tenth
         (10th) anniversary of the Commencement Date. Except as otherwise
         provided in this Agreement, the Option Agreement, a copy of which
         Executive has received and reviewed, shall govern the terms of the
         Option.

         (f) Restricted Stock. Subject to Executive commencing his employment
hereunder as the Company's President and Chief Executive Officer, no later than
ten (10) days after the Commencement Date, Executive shall be issued 75,000
shares of Common Stock (the "Restricted Stock") pursuant to the Stock Plan,
which shares shall vest as to 22,500 shares on each of the third and fourth
anniversaries of the Commencement Date and as to 30,000 shares on the fifth
anniversary of the Commencement Date. Executive shall pay $750 to the Company
for the Restricted Stock. The grant of the Restricted Stock shall be represented
by, and subject to, the terms of the Restricted Stock Agreement annexed hereto
as Exhibit B. Prior to the issuance of the Restricted Stock to the Executive,
the Company shall cause such issuance to be registered under the Securities Act
of 1933, as amended (the "1933 Act"), such that Executive will be able to sell
the Restricted Stock without complying with the holding period required under
Rule 144 promulgated under the 1933 Act.

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         (g) Vacation. Executive shall be entitled to vacations in accordance
with the policy of the Company with respect to its senior management, in effect
from time to time.

         (h) Tax and Financial Planning Services. During each year of the term
of this Agreement, Company agrees to reimburse Executive, up to $10,000 per
fiscal year, for the costs of all tax return preparation, including any United
States, state, or local returns, as well as for professional estate and
financial planning services, if any, with Executive choosing the tax and other
professionals who will provide such services. In addition, the Company shall pay
or reimburse the Executive for reasonable legal fees incurred in connection with
this Agreement.

         5. Noncompetition and Confidentiality Covenant.

         (a) Noncompetition. The "Noncompete Period" shall be (i) the period of
Executive's employment with the Company, and (ii) (A) the two (2) year period
immediately following termination of Executive's employment with the Company in
the event the Company terminates Executive's employment for Cause pursuant to
Section 9(a)(iii) hereof, Executive voluntarily terminates his employment (but
not any termination by Executive for Good Reason pursuant to Section 9(c)
hereof) or Executive's employment is terminated in a manner which entitles him
to severance payments under Section 10 hereof or (B) the one (1) year period
following termination of Executive's employment with the Company if the Term
ends as a result of a notice of non-renewal under Section 2 hereof. In
consideration for the compensation payable to Executive pursuant to this
Agreement, including without limitation the Option and Restricted Stock granted
to Executive hereunder, during the Noncompete Period, Executive will not
directly, or indirectly, whether as an officer, director, stockholder, partner,
proprietor, associate, employee, consultant, representative or otherwise,
become, or be interested in or associated with any other person, corporation,
firm, partnership or entity, engaged to a significant degree in (x) developing,
manufacturing, marketing or selling enzymes, protein-based biopharmaceuticals or
other pharmaceuticals that are modified using polyethylene glycol ("PEG"), (y)
developing, marketing or selling single-chain antigen-binding proteins or (z)
any technology or area of business in which the Company becomes involved to a
significant degree during the period of Executive's employment with the Company.
For purposes of the preceding sentence, to determine whether any entity is
engaged in such activities to a "significant degree", comparison will be made to
the Company's operations at that time. In other words, an entity will be deemed
to be engaged in an activity to a significant degree if the number of employees
and/or amount of funds devoted by such entity to such activity would be material
to the Company's operations at that time. Notwithstanding anything to the
contrary contained herein, Executive shall be entitled to work with or for (i)
an entity that is developing, marketing or manufacturing monoclonal antibodies,
(ii) a licensee of the Company if the only activities conducted by such licensee
that would be covered by the restrictions in this Section 5(a) are conducted
pursuant to, and covered by, the license granted by the Company and (iii) an
entity that is engaged in a research project that would be covered by the
restrictions in this Section 5(a) if such research project is not material to
such entity and Executive would have no direct involvement in such research
project; provided in the case of employment covered by clauses (ii) and (iii)
Executive shall have provided the Board with a detailed description of the
proposed employment and obtained the written consent of the Board (which consent
will not be unreasonably withheld) prior to commencing any such employment.
Executive is hereby prohibited from ever using any of the Company's proprietary
information or trade secrets to conduct any business, except for the Company's
business while Executive is employed by the Company as provided in Section 5(b)
hereof. The provisions contained in this Section 5(a) shall survive the
termination of Executive's employment pursuant to Section 9 hereof or otherwise.
In the event Executive breaches any of the covenants set forth in this Section
5(a), the running of the period of restriction set forth herein shall be tolled
for the period during which the breach exists and recommence upon Executive's
compliance with the terms of this Section 5(a).

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         (b) Confidentiality.

                  (i) Executive acknowledges that, by reason of his employment
         by the Company, he will have access to confidential information of the
         Company, including, but not limited to, information and knowledge
         pertaining to products, inventions, discoveries, improvements,
         innovations, designs, ideas, trade secrets, proprietary information,
         manufacturing, packaging, advertising, marketing, distribution and
         sales methods, sales and profit figures, customer and vendor lists and
         relationships between the Company and dealers, distributors, sales
         representatives, wholesalers, customers, suppliers and others who have
         business dealings with them ("Confidential Information"). The Executive
         acknowledges that such Confidential Information is a valuable and
         unique asset of the Company and covenants that, both during and after
         the Term, he will not disclose any Confidential Information to any
         person or entity, nor use the Confidential Information for any purpose,
         except as his duties as an employee of the Company may require, without
         the prior written authorization of the Board. The obligation of
         confidentiality imposed by this Section 5(b) shall not apply to
         Confidential Information that otherwise becomes generally known to the
         public through no act of the Employee in breach of this Agreement or
         any other party in violation of an existing confidentiality agreement
         with the Company or which is required to be disclosed by court order or
         applicable law.

                  (ii) All records, designs, patents, business plans, financial
         statements, manuals, memoranda, lists, research and development plans
         and products, and other property delivered to or compiled by Executive
         for or on behalf of the Company or its vendors or customers that
         pertain to the business of the Company shall be and remain the property
         of the Company, and be subject at all times to its discretion and
         control. Likewise, all formulae, correspondence, reports, records,
         charts, advertising materials and other similar data pertaining to the
         business, activities or future plans of the Company (and all copies
         thereof) that are collected by Executive shall be delivered promptly to
         the Company without request by it upon termination of Executive's
         employment.

         (c) Nonsolicitation of Employees. During the Noncompete Period,
Executive shall not, directly or indirectly, personally or through others,
encourage to leave employment with the Company, solicit for employment, or
advise or recommend to any other person, firm, business, or entity that they
employ or solicit for employment, any employee of the Company or of any parent,
subsidiary, or affiliate of the Company.

         6. Ventures. If, during the term of his employment, the Executive is
engaged in or associated with the planning or implementing of any project,
program, venture or relationship involving the Company and a third party or
parties, all rights in such project, program, venture or relationship shall
belong to the Company. Except as approved by the Board, the Executive shall not
be entitled to any interest in such project, program, venture or relationship or
to any commission, finder's fee or other compensation in connection therewith
other than the compensation to be paid to the Executive as provided in this
Agreement.

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         7. Acknowledgment. Executive agrees that the covenants and agreements
contained in Section 5 hereof are material to this Agreement; that each of such
covenants is reasonable and necessary to protect and preserve the Company's
interests, properties and business; that irreparable loss and damage will be
suffered by the Company should Executive breach any of such covenants and
agreements; that each of such covenants and agreements is separate, distinct and
severable not only from the other of such covenants and agreements but also from
the other and remaining provisions of this Agreement; that the unenforceability
or breach of any such covenants or agreement shall not affect the validity or
enforceability of any other such covenant or agreement or any other provision of
this Agreement; and that, in addition to other remedies available to it, the
Company shall be entitled to both temporary and permanent injunctions and any
other rights or remedies it may have, at law or in equity, to end or prevent a
breach or contemplated breach by Executive of any such covenants or agreements.

         (a) Geographic Extent of Executive's Obligations Concerning Section 5.
The restrictions contained in Section 5 are limited to the United States. Given
the nature of the Company's business, the restrictions contained in Section 5
cannot be limited to any particular geographic region within the United States.
Therefore, the obligations of Executive under Section 5 shall apply to any
geographic area in which the Company (i) has engaged in business during the
period of Executive's employment with the Company through its investment or
trading activities or otherwise, or (ii) has otherwise established during the
period of Executive's employment with the Company its goodwill, business
reputation or any customer or vendor relations.

         (b) Limitation of Covenant. Ownership by Executive, as a passive
investment, of less than five percent of the outstanding shares of capital stock
or equity of any corporation or other entity that is publicly traded shall not
constitute a breach of Section 5.

         (c) Blue Pencil Doctrine. The restrictions contained in Section 5 are
limited to the United States. If the duration or geographical extent of, or
business activities covered by, Section 5 are in excess of what is valid and
enforceable under applicable law, then such provision shall be construed to
cover only that duration, geographical extent or activities that are valid and
enforceable. Executive acknowledges the uncertainty of the law in this respect
and expressly stipulates that this Agreement be given the construction which
renders its provisions valid and enforceable to the maximum extent (not
exceeding its express terms) possible under applicable law.

         (d) Disclosure. Executive shall disclose to any prospective employer,
prior to accepting or continuing employment, the existence of Section 5 of this
Agreement and shall provide such prospective employer with a copy of Section 5
of this Agreement. The obligation imposed by this subsection 7(d) shall
terminate two years after the termination of Executive's employment with the
Company.

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         8. Intellectual Property and Related Matters.

         (a) Disclosure and Assignment. Executive will promptly disclose in
writing to the Company complete information concerning each and every product,
invention, discovery, practice, process or method, whether patentable or not,
made, developed, perfected, devised, conceived or first reduced to practice by
Executive, either solely or in collaboration with others, during the Term, or
within six months thereafter, whether or not during regular working hours,
relating either directly or indirectly to the business, products, practices or
techniques of the Company ("Developments"). Executive, to the extent that he has
the legal right to do so, hereby acknowledges that any and all of the
Developments are the property of the Company and hereby assigns and agrees to
assign to the Company any and all of Executive's right, title and interest in
and to any and all of the Developments. At the request of the Company, Executive
will confer with the Company and its representatives for the purpose of
disclosing all Developments to the Company, as the Company shall reasonably
request during the period ending one year after the Term.

         (b) Limitation on Section 8(a). The provisions of Section 8(a) shall
not apply to any Development meeting the following conditions:

                  (i) such Development was developed entirely on the Executive's
         own time;

                  (ii) such Development was made without the use of any Company
         equipment, supplies, facility or trade secret or customer information;

                  (iii) such Development does not relate (A) directly to the
         business of the Company or (B) to the Company's actual or demonstrably
         anticipated research or product or customer development; and

                  (iv) such Development does not result from any work performed
         by the Executive for the Company.

         (c) Assistance of Executive. Upon request and without further
compensation therefor, but at no expense to Executive, Executive will do all
lawful acts, including but not limited to, the execution of papers and lawful
oaths and the giving of testimony, that in the opinion of the Company, may be
necessary or desirable in enforcing the Company's intellectual property and
trade secret rights, and for perfecting, affirming and recording the Company's
complete ownership and title thereto.

         (d) Records. Executive will keep complete, accurate and authentic
accounts, notes, data and records of the Developments in the manner and form
requested by the Company. Such accounts, notes, data and records shall be the
property of the Company, and, upon the earlier of the Company's request or the
conclusion of his employment, Executive will promptly surrender same to the
Company.

         (e) Copyrightable Material. All right, title and interest in all
copyrightable material that Executive shall conceive or originate, either
individually or jointly with others, and which arise out of the performance of
this Agreement, will be the property of the Company and are by this Agreement
assigned to the Company along with ownership of any and all copyrights in the
copyrightable material. Upon request and without further compensation therefor,
but at no expense to Executive, Executive shall execute all papers and perform
all other acts necessary to assist the Company to obtain and register copyrights
on such materials in any and all countries. Where applicable, works of
authorship created by Executive for the Company in performing his
responsibilities under this Agreement shall be considered "works made for hire,"
as defined in the U.S. Copyright Act.

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         (f) Know-How and Trade Secrets. All know-how and trade secret
information conceived or originated by Executive that arises out of the
performance of his obligations or responsibilities under this Agreement or any
related material or information shall be the property of the Company, and all
rights therein are by this Agreement assigned to the Company.

         9. Termination of Employment.

         (a) Grounds for Termination. Executive's employment pursuant to this
Agreement shall terminate prior to the expiration of the Term in the event that
at any time:

                  (i) Executive dies,

                  (ii) Executive becomes disabled (as defined below), so that he
         cannot perform the essential functions of his position with or without
         reasonable accommodation,

                  (iii) The Board elects to terminate Executive's employment for
         "Cause" and notifies Executive in writing of such election, or

                  (iv) The Board elects to terminate Executive's employment
         without "Cause" and notifies Executive in writing of such election.

         If Executive's employment is terminated pursuant to clause (i), (ii) or
(iii) of this Section 9(a), such termination shall be effective immediately. If
Executive's employment is terminated pursuant to subsection (iv) of this Section
9(a), such termination shall be effective 30 days after delivery of the notice
of termination.

         (b) "Cause" Defined. "Cause" shall mean (i) the willful engaging by
Executive in illegal conduct or gross misconduct which is demonstrably and
materially injurious to the Company, (ii) Executive's refusal to attempt to
perform his obligations to the Company hereunder (other than any such failure
resulting from illness or incapacity), which refusal is demonstrably and
materially injurious to the Company, but only after Executive has first received
prior written notice of such alleged refusal, and fifteen (15) days thereafter
to perform his obligations to the Company, or (iii) Executive's breach of his
obligations under this Agreement, which breach is demonstrably and materially
injurious to the Company, but only after Executive has first received prior
written notice of such alleged breach and fifteen (15) days thereafter to
perform his obligations to the Company For purposes of this Section 9(b), no act
or failure to act on Executive's part shall be deemed "willful" unless done, or
omitted to be done, by Executive not in good faith and without reasonable belief
that Executive's action of omission was in the best interest of the Company.
Notwithstanding the foregoing, Executive shall not be deemed to have been
terminated for Cause unless and until the Company delivers to Executive a copy
of a resolution duly adopted by the affirmative vote of not less than
three-quarters of the entire membership of the Board (not including Executive)
at a meeting of the Board called and held for such purpose (after reasonable
notice to Executive and an opportunity for Executive, together with counsel, to
be heard before the Board) finding that, in the good faith opinion of the Board,
Executive engaged in conduct set forth above and specifying the particulars
thereof in reasonable detail.

                                       10
<PAGE>

         (c) Termination by Executive for Good Reason. Executive's employment
pursuant to this Agreement may be terminated by Executive prior to the
expiration of the Term in the event Executive has a "Good Reason" to terminate
his employment, which shall mean the following:

                  (i) Any material adverse change in Executive's status or
         position, including, without limitation, any material adverse change in
         Executive's status or position as a result of a diminution in
         Executive's position, duties, responsibilities or authority or the
         assignment to Executive of any duties or responsibilities which are
         inconsistent with Executive's status or position, or any removal of
         Executive from or any failure to reappoint or reelect Executive to such
         positions, it being understood that Executive's not holding the
         positions of President, Chief Executive Officer and Chairman of the
         Board, at any time and for any reason without the Executive's written
         consent will constitute Good Reason hereunder; or

                  (ii) The failure of the Board to continue to maintain
         Executive as Chairman of the Board at all times during the Term; or

                  (iii) The failure of the Board to nominate Executive for
         reelection to the Board and recommend to the Company's stockholders
         that they vote in favor of Executive's reelection to the Board upon
         expiration of Executive's term on the Board at any time during the
         Term; or

                  (iv) A reduction in Executive's annual Base Salary as the same
         may be increased from time to time or failure to pay same; or

                  (v) A reduction in the Target Bonus which could be paid to
         Executive under the Bonus Plan below 100% of Executive's Base Salary or
         a failure to pay when due any Earned Bonus (including, without
         limitation, the guaranteed bonus for the fiscal year ending June 30,
         2005 under Section 4(c) hereof), provided however, that the Company's
         failure to actually award any bonus to Executive, or the Company's
         actually awarding a bonus to Executive which is less than the Target
         Bonus, shall not constitute Good Reason; or

                  (vi) The breach by the Company of any of its material
         obligations under this Agreement; or

                  (vii) The relocation of the Company's principal executive
         offices to a location more than thirty-five (35) miles from the
         location of such offices or the Company requiring Executive to be based
         anywhere other than the Company's principal executive offices, except
         for required travel substantially consistent with Executive's business
         obligations.

                                       11
<PAGE>

         Prior to the Executive being permitted to terminate his employment for
Good Reason, the Company shall have sixty (60) days to cure any such alleged
breach, assignment, reduction or requirement, after Executive provides the
Company written notice of the actions or omissions constituting such breach,
assignment, reduction or requirement.

         (d) "Change of Control" Defined. Change of Control means the following:

                  (i) "Board Change" which, for purposes of this Agreement,
         shall have occurred if, over any twenty-four month period, a majority
         of the seats (other than vacant seats) on the Company's Board were to
         be occupied by individuals who were neither (A) nominated by at least
         one-half (1/2) of the directors then in office (but excluding, for this
         purpose, any such individual whose initial assumption of office occurs
         as a result of either an actual or threatened election contest or other
         actual or threatened solicitation of proxies or consents by or on
         behalf of a Person (as defined herein) other than the Board) nor (B)
         appointed by directors so nominated, or

                  (ii) the acquisition by any individual, entity or group
         (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities
         Exchange Act of 1934 (the "Exchange Act"), (a "Person") of beneficial
         ownership (within the meaning of Rule 13d-3 promulgated under the
         Exchange Act) of a majority of the then outstanding voting securities
         of the Company (the "Outstanding Company Voting Securities"); provided,
         however, that the following acquisitions shall not constitute a Change
         of Control: (A) any acquisition by the Company, or (B) any acquisition
         by any employee benefit plan (or related trust) sponsored or maintained
         by the Company or any corporation controlled by the Company, or (C) any
         public offering or private placement by the Company of its voting
         securities; or

                  (iii) a consolidation of the Company with another entity or a
         merger of the Company with another entity in which neither the Company
         nor a corporation that, prior to the merger or consolidation, was a
         subsidiary of the Company, shall be the surviving entity; or

                  (iv) a merger or consolidation of the Company following which
         either the Company or a corporation that, prior to the merger or
         consolidation, was a subsidiary of the Company, shall be the surviving
         entity and a majority of the Outstanding Company Voting Securities is
         owned by a Person or Persons who were not "beneficial owners" of a
         majority of the Outstanding Company Voting Securities immediately prior
         to such merger or consolidation; or

                  (v) a voluntary or involuntary liquidation of the Company; or

                  (vi) a sale or disposition by the Company of at least 80% of
         its assets in a single transaction or a series of transactions (other
         than a sale or disposition of assets to a subsidiary of the Company in
         a transaction not involving a Change of Control or a change in control
         of such subsidiary).

          (e) "Disabled" Defined. As used in this Agreement, the term "disabled"
means any mental or physical condition that renders Executive unable to perform
the essential functions of his position, with or without reasonable
accommodation, for a period in excess of 180 days.

                                       12
<PAGE>

         (f) Surrender of Records and Property. Upon termination of his
employment with the Company, Executive shall deliver promptly to the Company all
records, manuals, books, lists, blank forms, documents, letters, memoranda,
notes, notebooks, reports, data, tables, calculations or copies thereof that
relate in any way to the business, products, practices or techniques of the
Company, and all other property, trade secrets and confidential information of
the Company, including, but not limited to, all documents that in whole or in
part contain any trade secrets or confidential information of the Company, which
in any of these cases are in his possession or under his control.

         10. Effect of Termination.

         (a) Termination Without Cause or for Good Reason .

         In the event the Company terminates Executive's employment as the
Company's President and Chief Executive Officer without Cause pursuant to
Section 9(a)(iv) hereof or Executive terminates such employment for Good Reason
pursuant to Section 9(c) hereof,

                  (i) Executive shall receive a lump sum cash payment equal to
        the sum of (1) any Base Salary payable through the date of termination
        and any Earned Bonus which remains unpaid as of the date of termination;
        (2) an amount equal to 400% of the Executive's Base Salary in effect at
        the time of his termination (or, if greater, the highest Base Salary in
        effect for any prior year); and (3) the pro rata portion of the Target
        Bonus (based on the Base Salary described in (i)(2) above) for the
        period worked during the fiscal year in which his termination occurs;

                  (ii) if Executive, and any spouse and/or dependents ("Family
        Members") has medical and dental coverage on the date of such
        termination under a group health plan sponsored by the Company, then,
        for the first 18 months following the date of such termination, the
        Company will pay the full cost of continuing medical and dental coverage
        for the Executive and his covered family members under the Consolidated
        Omnibus Budget Reconciliation Act of 1986, 29 U.S.C. Sections 1161-1168;
        26 U.S.C. Section 4980B(f), as amended, and all applicable regulations
        (referred to collectively as "COBRA"), provided, that the Company shall
        have no obligation to pay for such COBRA coverage if and to the extent
        the Executive and his Family Members become entitled to receive
        comparable benefits from and at the expense of a subsequent employer;

                  (iii) the restricted stock (and/or cash equivalent, if any)
        granted to Executive pursuant to Section 3(b)(ii) and the Restricted
        Stock granted pursuant to Section 4(f) hereof shall vest immediately
        upon termination;

                  (iv) to the extent the Option granted to Executive pursuant to
        Section 4(e) hereof has not vested at the time of such termination the
        Option will vest immediately upon termination;

                  (v) the Option granted to Executive pursuant to Section 4(e)
        hereof which has vested or become vested at the time or as a result of
        such termination will remain exercisable until its expiration date; and

                                       13
<PAGE>

                  (vi) Executive shall continue to be entitled to any deferred
        compensation and other unpaid amounts and benefits earned and vested
        prior to or as a result of Executive's termination.

         (b) Termination For Cause. In the event the Company terminates
Executive's employment as the Company's President and Chief Executive Officer
for Cause pursuant to Section 9(a)(iii) hereof, (i) Executive shall be entitled
to receive payment of any Base Salary payable through the date of termination
and any Earned Bonus which remains unpaid as of the date of termination, (ii)
Executive shall continue to be entitled to any deferred compensation and other
unpaid amounts and benefits earned and vested prior to Executive's termination,
(iii) to the extent the Option granted to Executive pursuant to Section 4(e)
hereof has vested prior to the date of Executive's termination the Option shall
remain exercisable with respect to such vested portion of the Option for a
period of six months following Executive's termination, (iv) to the extent the
Option granted to Executive pursuant to Section 4(e) hereof has not vested prior
to the date of Executive's termination the Option will terminate with respect to
such unvested portion of the Option as of the date of such termination and will
be of no further force and effect, and (v) Executive will forfeit all unvested
restricted stock (and/or cash equivalent, if any) granted to Executive pursuant
to Section 3(b)(ii) and the Restricted Stock granted pursuant to Section 4(f)
hereof.
         (c) Death. In the event Executive's employment as the Company's
President and Chief Executive Officer is terminated as a result of Executive's
death, (i) Executive's estate or Executive's duly designated beneficiaries shall
be entitled to payment of any Base Salary payable through the date of
Executive's death and any Earned Bonus which remains unpaid as of the date of
Executive's death, (ii) Executive's estate or Executive's duly designated
beneficiaries shall be entitled to a pro rata amount of the Target Bonus (based
on the Base Salary at the time of death) for the fiscal year in which he dies,
(iii) the Option granted under Section 4(e) hereof and the restricted stock
(and/or cash equivalent, if any) granted under Section 3(b)(ii) and the
Restricted Stock granted pursuant to Section 4(f) hereof shall become fully
vested and, if applicable, exercisable, with the Option remaining exercisable
until the earlier of (A) three years from the date of death and (B) the end of
the remaining stated exercise term of the Option, and (iv) Executive's estate or
Executive's duly designated beneficiaries shall continue to be entitled to any
deferred compensation and other unpaid amounts and benefits earned and vested
prior to Executive's death. If Executive's Family Members have medical and
dental coverage on the date of such termination under a group health plan
sponsored by the Company, the Company will reimburse such Family Member for the
total applicable premium cost for medical and dental coverage under COBRA for
such Family Members for a period of up to thirty-six (36) months commencing on
the date of such termination; provided the Company shall have no obligation to
reimburse such Family Members for the premium cost of COBRA coverage as of the
date they become eligible to obtain comparable benefits from another employer.

                                       14
<PAGE>

         (d) Disability. Upon termination of Executive's employment as the
Company's President and Chief Executive Officer on account of Executive's
disability pursuant to Section 9(a)(ii) hereof, (i) Executive shall be entitled
to payment of any Base Salary payable through the commencement of long term
disability payments to Executive under any plan provided or paid for by the
Company and any Earned Bonus which remains unpaid as of the date of the
termination of employment, (ii) Executive shall be entitled to a pro rata amount
of the Target Bonus (based on the Base Salary at the time of such termination)
for the fiscal year in which his employment is terminated, (iii) Executive shall
be entitled to all compensation and benefits to which Executive is entitled
pursuant to the Company's disability policies in effect as of the date of
Executive's termination, (iv) the Option granted under Section 4(e) hereof and
the restricted stock (and/or cash equivalent, if any) granted under Section
3(b)(ii) and the Restricted Stock granted pursuant to Section 4(f) hereof shall
become fully vested and, if applicable, exercisable, with the Option remaining
exercisable until the earlier of (A) three years from the date of such
termination of Executive's employment on account of Executive's disability and
(B) the end of the remaining stated exercise term of the Option; and (v)
Executive shall continue to be entitled to any deferred compensation and other
unpaid amounts and benefits earned and vested prior to or as a result of
Executive's termination. If Executive and his Family Members have medical and
dental coverage on the date of such termination under a group health plan
sponsored by the Company, the Company will reimburse Executive for the total
applicable premium cost for medical and dental coverage under COBRA for
Executive and his Family Members for a period of up to eighteen (18) months
commencing on the date of such termination; provided the Company shall have no
obligation to reimburse Executive and his Family Members for the premium cost of
COBRA coverage as of the date they become eligible to obtain comparable benefits
from another employer.

         (e) Voluntary Resignation. In the event Executive voluntarily
terminates his employment as the Company's President and Chief Executive
Officer, other than for Good Reason, or delivers to the Company a notice of
non-renewal of this Agreement pursuant to Section 2 hereof, (i) Executive shall
be entitled to receive payment of any Base Salary payable through the date of
termination and any Earned Bonus which remains unpaid as of the date of
termination, (ii) Executive shall continue to be entitled to any deferred
compensation and other unpaid amounts and benefits earned and vested prior to
Executive's termination, (iii) to the extent the Option granted to Executive
pursuant to Section 4(e) hereof has vested prior to the date of such termination
the Option shall remain exercisable with respect to such vested portion of the
Option for a period of twelve months following such termination, (iv) to the
extent the Option granted to Executive pursuant to Section 4(e) hereof has not
vested prior to the date of such termination the Option will terminate with
respect to such unvested portion of the Option as of the date of such
termination and will be of no further force and effect, and (v) Executive will
forfeit all unvested restricted stock (and/or cash equivalent, if any) granted
to Executive pursuant to Section 3(b)(ii) and all unvested Restricted Stock
granted pursuant to Section 4(f) hereof.

         (f) Termination Without Cause or For Good Reason In Connection With A
Change in Control. In the event the Company terminates Executive's employment as
the Company's President and Chief Executive Officer without Cause pursuant to
Section 9(a)(iv) hereof or Executive terminates such employment for Good Reason
pursuant to Section 9(c) hereof within the period which commences ninety (90)
days before and ends two (2) years following a Change in Control, in lieu of the
provisions of Section 10(a) hereof,

                  (i) Executive shall receive a lump sum cash payment equal to
         the sum of (1) any Base Salary payable through the date of termination
         and any Earned Bonus which remains unpaid as of the date of
         termination, (2) the pro rated portion of the Target Bonus (based on
         the Base Salary at the time of such termination or, if higher, at the
         time during the 12 months preceding the Change in Control) for the
         period worked during the fiscal year in which such termination occurs,
         and (3) the product of 6 and Executive's annual rate of Base Salary at
         the time of such termination (or, if higher, at any time during the 12
         months preceding the Change in Control);

                                       15
<PAGE>

                  (ii) if Executive and his Family Members have medical and
         dental coverage on the date of such termination under a group health
         plan sponsored by the Company, then, for the first 18 months following
         the date of such termination, the Company will pay the full cost of
         continuing medical and dental coverage for the Executive and his
         covered family members under COBRA; provided, that the Company shall
         have no obligation to pay for COBRA coverage if and to the extent the
         Executive and his Family Members become entitled to receive comparable
         benefits from and at the expense of a subsequent employer; and

                  (iii) Executive shall continue to be entitled to any deferred
         compensation and other unpaid amounts and benefits earned and vested
         prior to Executive's termination.

         In the event the Executive becomes entitled to payments and/or the
accelerated vesting of the Option and/or restricted stock under this Section
10(f) or Section 10(h) or any other payments or benefits which are deemed to
contingent upon a change in ownership or control pursuant to Section 280G of the
Internal Revenue Code ("Code"), the Company shall cause its independent auditors
promptly to review, at the Company's expense, the applicability of Section 4999
of the Code to such payments and/or vesting. If such auditors shall determine
that any payment or distribution of any type by the Company to Executive,
whether paid or payable or distributed or distributable pursuant to the terms of
this Agreement or otherwise (the "Total Payments"), would be subject to the
excise tax imposed by Section 4999 of the Code, or any interest or penalties
with respect to such excise tax (such excise tax, together with any such
interest and penalties, are collectively referred to as the "Excise Tax"), then
Executive shall be entitled to receive an additional cash payment (a "Gross-Up
Payment") within 30 days of such determination equal to an amount such that
after payment by Executive of all taxes (including any interest or penalties
imposed with respect to such taxes), including any Excise Tax, imposed upon the
Gross-Up Payment, Executive would retain an amount of the Gross-Up Payment equal
to the Excise Tax imposed upon the Total Payments. For purposes of the foregoing
determination, Executive's tax rate shall be deemed to be the highest statutory
marginal state and Federal tax rate (on a combined basis) (including his share
of F.I.C.A. and Medicare taxes) then in effect. If no determination by the
Company's auditors is made prior to the time a tax return reflecting the Total
Payments is required to be filed by Executive, Executive will be entitled to
receive a Gross-Up Payment calculated on the basis of the Total Payments
reported by Executive in such tax return, within 30 days of the filing of such
tax return. In all events, if any tax authority determines that a greater Excise
Tax should be imposed upon the Total Payments than is determined by the
Company's independent auditors or reflected in Executive's tax return pursuant
to this Section 10(f), the Executive shall be entitled to receive the full
Gross-Up Payment calculated on the basis of the amount of Excise Tax determined
to be payable by such tax authority from the Company within 30 days of such
determination.

         (g) All payments made to Executive under any of the subsections of this
Section 10 which are based upon Executive's salary or Bonus shall be made at or
as soon as practicable after the termination of Executive's employment.

                                       16
<PAGE>

         (h) Notwithstanding anything to the contrary contained herein or in any
other agreement or plan, immediately prior to the occurrence of a Change of
Control, the Option granted under Section 4(e) hereof and the restricted stock
(and/or cash equivalent, if any) granted under Section 3(b)(ii) and the
Restricted Stock granted pursuant to Section 4(f) hereof shall become fully
vested and, if applicable, exercisable, it being understood that Executive will
be entitled to participate in such transaction with respect to all of the shares
covered by such awards.

         (i) Notwithstanding anything to the contrary contained herein, if
Executive's employment with the Company terminates or is deemed terminated
before the payment in full of the $412,500 guaranteed minimum bonus for 2005
(described in Section 4(b) hereof) and the Consulting Agreement Payments
(determined under Section 3(b) hereof), then, unless Executive's employment is
terminated by him voluntarily without Good Reason or by the Company for Cause,
the Executive shall be entitled to receive from the Company (1) the full amount
of the guaranteed minimum bonus promptly after the termination of his
employment, and (2) the balance of the Consulting Agreement Payments as and when
they would have been payable if Executive's employment with the Company had
continued.

         11. Miscellaneous.

         (a) Entire Agreement. This Agreement (including the exhibits, schedules
and other documents referred to herein) contains the entire understanding
between the parties hereto with respect to the subject matter hereof and
supersedes any prior understandings, agreements or representations, written or
oral, relating to the subject matter hereof.

         (b) Counterparts. This Agreement may be executed in separate
counterparts, each of which will be an original and all of which taken together
shall constitute one and the same agreement, and any party hereto may execute
this Agreement by signing any such counterpart.

         (c) Severability. Whenever possible, each provision of this Agreement
shall be interpreted in such a manner as to be effective and valid under
applicable law but if any provision of this Agreement is held to be invalid,
illegal or unenforceable under any applicable law or rule, the validity,
legality and enforceability of the other provision of this Agreement will not be
affected or impaired thereby.

         (d) Successors and Assigns. This Agreement shall be binding upon and
inure to the benefit of the parties hereto and their respective heirs, personal
representatives and, to the extent permitted by subsection (e), successors and
assigns. The Company will require its successors to expressly assume its
obligations under this Agreement.

         (e) Assignability. Neither this Agreement nor any right, remedy,
obligation or liability arising hereunder or by reason hereof shall be
assignable (including by operation of law) by either party without the prior
written consent of the other party to this Agreement, except that the Company
may, without the consent of the Executive, assign its rights and obligations
under this Agreement to any corporation, firm or other business entity with or
into which the Company may merge or consolidate, or to which the Company may
sell or transfer all or substantially all of its assets, or of which 50% or more
of the equity investment and of the voting control is owned, directly or
indirectly, by, or is under common ownership with, the Company. After any such
assignment by the Company, and provided that such assignment arises by operation
of law or involves an express written assumption by the assignee, the Company
shall be immediately released and discharged from all further liability
hereunder and such assignee shall thereafter be deemed to be the Company for the
purposes of all provisions of this Agreement.

                                       17
<PAGE>

         (f) Modification, Amendment, Waiver or Termination. No provision of
this Agreement may be modified, amended, waived or terminated except by an
instrument in writing signed by the parties to this Agreement. No course of
dealing between the parties will modify, amend, waive or terminate any provision
of this Agreement or any rights or obligations of any party under or by reason
of this Agreement. No delay on the part of the Company in exercising any right
hereunder shall operate as a waiver of such right. No waiver, express or
implied, by the Company of any right or any breach by Executive shall constitute
a waiver of any other right or breach by Executive.

         (g) Notices. All notices, consents, requests, instructions, approvals
or other communications provided for herein shall be in writing and delivered by
personal delivery, overnight courier, mail, electronic facsimile or e-mail
addressed to the receiving party at the address set forth herein. All such
communications shall be effective when received.

Address for the Executive:

                           Jeffrey H. Buchalter
                           150 Manchester Way
                           San Antonio, Texas 78249

or his home address subsequent to his relocation to the New Jersey area in
connection with his duties under this Agreement.

Address for the Company:

                           Enzon Pharmaceuticals, Inc.
                           685 Route 202/206
                           Bridgewater, New Jersey 08807
                           Attn:  General Counsel

Any party may change the address set forth above by notice to each other party
given as provided herein.

         (h) Headings. The headings contained in this Agreement are for
reference purposes only and shall not in any way affect the meaning or
interpretation of this Agreement.

         (i) Governing Law. ALL MATTERS RELATING TO THE INTERPRETATION,
CONSTRUCTION, VALIDITY AND ENFORCEMENT OF THIS AGREEMENT SHALL BE GOVERNED BY
THE INTERNAL LAWS OF THE STATE OF NEW JERSEY, WITHOUT GIVING EFFECT TO ANY
CHOICE OF LAW PROVISIONS THEREOF.

         (j) Resolution of Certain Claims - Injunctive Relief. The Executive
acknowledges that it would be difficult to fully compensate the Company for
damages resulting from any breach by him of the provisions of this Agreement.
Accordingly, the Executive agrees that, in addition to, but not to the exclusion
of any other available remedy, the Company shall have the right to enforce the
provisions of Sections 5 through 8 or 9(f) by applying for and obtaining
temporary and permanent restraining orders or injunctions from a court of
competent jurisdiction without the necessity of filing a bond therefor, and
without the necessity of proving actual damages, and the Company shall be
entitled to recover from the Executive its reasonable attorneys' fees and costs
in enforcing the provisions of Sections 5 through 8 or 9(f).

                                       18
<PAGE>

         (k) Arbitration. Except as otherwise specifically provided for
hereunder, any claim or controversy arising out of or relating to this Agreement
or the breach hereof shall be settled by arbitration in accordance with the laws
of the State of New Jersey. Such arbitration shall be conducted in the State and
City of New Jersey in accordance with the rules then existing of the American
Arbitration Association which pertain to employment disputes. Judgment upon the
award rendered by the arbitrators may be entered in any court having
jurisdiction thereof. In the event of any dispute arising under this Agreement,
the respective parties shall be responsible for the payment of their own legal
fees and disbursements.

         (l) Board Approval. On or prior to the Effective Date, the Company
shall provide Executive with a copy of the duly adopted resolutions of its Board
approving the terms of this Agreement, electing the Executive to the positions
of President and Chief Executive Officer effective as of the Commencement Date
and (if not already effected) electing Executive to the Board effective as of
the Commencement Date.

         (m) Third-Party Benefit. Nothing in this Agreement, express or implied,
is intended to confer upon any other person any rights, remedies, obligations or
liabilities of any nature whatsoever.

         (n) Withholding Taxes. The Company may withhold from any benefits
payable under this Agreement all federal, state, city or other taxes as shall be
required pursuant to any law or governmental regulation or ruling.

         IN WITNESS WHEREOF, the parties hereto have executed this Employment
Agreement as of the Effective Date.


ENZON PHARMACEUTICALS, INC.


By: /s/ Kenneth J. Zuerblis
   --------------------------------
     Kenneth J. Zuerblis
     Chief Financial Officer



EXECUTIVE


   /s/ Jeffrey H. Buchalter
   --------------------------------
     Jeffrey H. Buchalter


                                       19