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                                                                   Exhibit 10.24

            Amendment to Employment Agreement, dated as of February 27,
            2004 (this "Agreement"), among Memory Pharmaceuticals Corp., a
            Delaware corporation (the "Company") and Axel Unterbeck (the
            "Executive")

            The Executive and the Company entered into a Employment Agreement
dated as of January 5, 1998 (the "Original Employment Agreement").

            The Original Employment Agreement was amended by a letter agreement
dated as of November 12, 1999, March 4, 2002 and August 20, 2002, each between
the Company and the Executive (the Original Employment Agreement as amended by
such amendments is referred to as the "Existing Employment Agreement").

            The Executive and the Company desire to further amend the Existing
Employment Agreement as set forth herein (the Existing Employment Agreement as
amended by this Agreement shall hereinafter be the "Employment Agreement").

            In consideration of the premises and the mutual covenants and
agreements hereinafter contained the receipt and sufficiency of which is
acknowledged, the parties agree as follows:

            1. Definitions; Conflicts. Unless otherwise specified, all
capitalized terms used but not defined in this Agreement have the meanings
ascribed to such terms in the Existing Employment Agreement. Except as
specifically amended by this Agreement, the Existing Employment Agreement
remains in full force and effect. Wherever the terms of this Agreement and the
Existing Employment Agreement conflict, this Agreement shall control.

            2. Amendments to Existing Employment Agreement. The Existing
Employment Agreement shall be amended as follows:

                  a. Section 3(c) is hereby deleted in its entirety, and in lieu
thereof, there is substituted the following:

                  "(c) Annual Bonus. You will be eligible to receive annual
                  bonus payments dependent on the performance of the Company and
                  your individual performance, subject to the discretion of the
                  Board of Directors. Your target bonus will be equal to
                  ___________ (__%) of your base salary, assuming the
                  achievement of such Company and individual performance
                  objectives."

                  b. Section 7(c) is hereby deleted in its entirety, and in lieu
thereof, there is substituted the following:

                  "(c) Severance. Upon termination for any reason, the Company
                  will pay you within two weeks of such termination, your
                  current base salary earned through the
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                  termination date, plus accrued vacation, if any, and other
                  benefits or payments, if any, to which you are entitled. In
                  the event you are terminated by the Company, without Cause,
                  then the Company will continue to pay you your bi-weekly rate
                  in effect at the time of termination and provide and pay the
                  Company's portion of your medical, dental, life and disability
                  insurance for a period of six (6) months. Further, for the
                  period commencing seven months following such termination and
                  ending twelve months after such termination, the Company will
                  continue to pay you your bi-weekly rate in effect at the time
                  of termination and provide and pay the Company's portion of
                  your medical, dental, life and disability insurance, except
                  that such severance payments made to you during this period
                  will be reduced by all 1099 and W-2 income earned or received
                  by you during such period, including income earned or received
                  from consulting services or temporary employment, and the
                  Company's payments for your medical, dental, life and
                  disability insurance will terminate when you have such
                  coverage through any new employer before the end of the twelve
                  month period following your termination. The Company will
                  reconcile such payments with you quarterly, and any additional
                  payments owed to you by the Company, and any payments owed to
                  the Company by you, will be paid respectively within two weeks
                  following such reconciliation period. In addition, if you were
                  terminated by the Company without Cause, you will be entitled
                  to accelerated vesting of twenty-five percent (25%) of your
                  unvested stock options as of the date of your termination of
                  employment. Your unvested stock options will become fully
                  vested in connection with an acquisition of the Company, under
                  circumstances where the terms of your employment are changed
                  or your employment is terminated by the acquiring company, in
                  accordance with the terms of the Company's 1998 Employee,
                  Director and Consultant Stock Option Plan (a copy of which has
                  been provided to you). The Company will not be obligated to
                  continue any such payments to you or accelerate vesting of
                  your stock options under this Section 7(c) in the event you
                  materially breach any of the provisions of Sections 4, 5 or 6.
                  Notwithstanding any termination of your employment, you will
                  continue to be bound by the provisions of Sections 4, 5 and 6.


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            3. Miscellaneous. This Agreement constitutes the entire
understanding of the parties with respect to the subject matter hereof and
supersedes any and all prior understandings and agreements, whether written or
oral, with respect to such subject matter. This Agreement may be executed in
counterparts, which together shall constitute one and the same instrument. Any
amendment or modification of this Agreement or waiver of any right, in whole or
in part, will be effective only if it is in writing and signed by the parties
hereto. This Agreement shall be governed by and construed in accordance with the
laws (other than the conflict of laws rules) of the State of New Jersey.


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            IN WITNESS WHEREOF, each of the parties has caused this Agreement to
be duly executed and delivered as of the date first above written.


                                     Memory Pharmaceuticals Corp.


                                     By:
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                                         Name: Tony Scullion
                                         Title: Chief Executive Officer


                                     -------------------------------------------
                                     Axel Unterbeck