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                                                                   Exhibit 10.15

[MEMORY LOGO]
MEMORY PHARMACEUTICALS CORP.
100 Philips Parkway
Montvale, New Jersey 07645
Phone: (201)802-7100
Fax: (201) 802-7170
www.memorypharma.com

August 14, 2002

Dr. Axel Unterbeck
205 Wildwood Avenue
Madison, CT 06443-0662

Dear Axel:

      We are pleased to inform you that the Compensation Committee of the Board
of Directors of Memory Pharmaceuticals Corp. (the "Company") has agreed to
provide you with the following benefits:

      1.  Relocation Expenses.  The Company will pay or reimburse you for all
          reasonable out-of-pocket relocation and relocation-related expenses
          not to exceed $150,000, including any Tax Payment (as defined below)
          and any Gross-up Payment (as defined below), which may be billed
          directly to the Company or paid by you and submitted for
          reimbursement, including, without limitation, the following:

          (a) costs of services of moving companies (including packing,
              transportation and relocation expenses);

          (b) costs attendant to the sale of your current residence and the
          purchase of a new residence within fifty (50) miles of the Company's
          principal offices in Montvale, New Jersey including, without
          limitation, the costs of home inspections, survey, appraisal, title
          insurance, transfer fees, attorney's fees, accountants' fees and
          closing costs);

          (c) commissions payable to brokers in connection with the sale of your
          current residence;

          (d) loan origination fees (points) related to the purchase of your new
          residence in an amount of up to three percent (3%) of the loan amount
          (and the Company will provide assistance to you relating to the
          selection of a mortgage lender that will pre-qualify you for a
          mortgage loan to purchase your new residence.

      All such payments will be subject to the Company receiving reasonably
acceptable documentation evidencing the incurring of such cost, expense or fee.
In the event that it should be determined that any payment shall be due by you
for taxes of any kind or nature relating to amounts paid to you or on your
behalf by the Company in connection with your relocation as provided above
("Taxes"), the Company will deliver to you a payment equal to the amount of
such Taxes (the "Tax Payment") plus an additional payment in an amount equal to
any additional taxes payable by you applicable to your receipt of the Tax
Payment (the "Gross-Up Payment").





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     Such allowance for Relocation Expenses will expire in the event that a new
home is not purchased by December 31, 2002. This date is not extendable.

     2.   Interest Free Loan.

          (a) The Company will make available to you through December 31, 2002,
          upon your request in writing, an interest free loan in the amount of
          up to Three Hundred Thousand Dollars ($300,000) for a period of three
          (3) years following the date of the loan to enable you to purchase a
          residence within fifty (50) miles of the Company's principal offices
          in Montvale, New Jersey, with such loan secured by a mortgage on the
          residence to be acquired by you, marketable securities (at a
          loan-to-value ratio of fifty percent (50%)) or other collateral
          mutually agreed upon by the parties, as more fully described in a Loan
          Agreement which you and the Company will enter into with respect
          thereto. The Company will further agree to forgive amounts owed by you
          in connection with this loan in equal installments each year ($100,000
          per year) over a period of three (3) years, starting January 1, 2002
          and will further agree to forgive all amounts owed by you in
          connection with this loan in the event you are terminated without
          Cause; in the event you are terminated with Cause or should you
          voluntarily terminate your employment all unforgiven amounts owed by
          you and taxes attendant thereto in connection with this loan will be
          immediately due and payable to the Company; and it being understood
          and agreed that your rights under this Section 2 shall not be
          adversely affected solely by reason of any bankruptcy of the Company.
          In the event that it should be determined that any payment shall be
          due by you for taxes of any kind or nature relating to amounts paid to
          you or on your behalf by the Company in connection with this loan
          ("Taxes"), the Company will deliver to you a payment equal to the
          amount of such Taxes (the "Tax Payment") plus an additional payment in
          an amount equal to any additional taxes payable by you applicable to
          your receipt of the Tax Payment (the "Gross-Up Payment").

          (b) If you decide not to purchase a new home by December 31, 2002, you
          may at any time up to December 31, 2002 (a non-extendable date), elect
          to receive a forgivable loan from the Company in the amount of
          $100,000. At such time, the $300,000 loan mentioned above will no
          longer be available. The Company will agree to forgive amounts owed by
          you in connection with this $100,000 loan in equal installments each
          year ($33,333 per year) over a period of three (3) years, starting
          January 1, 2002 and will further agree to forgive all amounts owed by
          you in connection with this loan in the event you are terminated
          without Cause; in the event you are terminated with Cause or should
          you voluntarily terminate your employment all unforgiven amounts owed
          by you and taxes attendant thereto in connection with this loan will
          be immediately due and payable to the Company; and it being understood
          and agreed immediately due and payable to the Company; and it being
          understood and agreed that your rights under this Section 2 shall not
          be adversely affected solely by reason of any bankruptcy of the
          Company. In the event that it should be determined that any payment
          shall be due by you for taxes of any kind or nature relating to
          amounts paid to you or on your behalf by the Company in connection
          with this loan ("Taxes"), the Company will deliver to you a payment
          equal to the amount of such Taxes (the "Tax Payment") plus an
          additional payment in an amount equal to any additional taxes payable
          by you applicable to your receipt of the Tax Payment (the "Gross-Up
          Payment").

          (c) For the purposes of this Section 2, "Cause" shall include (i) your
          conviction of a felony, either in connection with the performance of
          your obligations to the Company or otherwise, which adversely affects
          your ability to perform such obligations or materially adversely
          affects the business activities, reputation, goodwill or image of the
          Company, (ii) your willful disloyalty, deliberate dishonesty, breach
          of fiduciary duty, (iii) your breach of the terms of this Agreement,
          or your failure or refusal to carry out any

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          material tasks assigned to you by the Company in accordance with the
          terms hereof, which breach or failure continues for a period of more
          than thirty (30) days after your receipt of written notice thereof
          from the Company, (iv) the commission by you of any act of fraud,
          embezzlement or deliberate disregard of a significant rule or policy
          of the Company known to you or contained in a policy and procedure
          manual provided to you which results in material loss, damage or
          injury to the Company, or (v) the material breach by you of any of the
          confidentiality or non-complete provisions contained in the letter
          agreement dated January 5, 1998 previously entered into between you
          and the Company.

     3.   General.

          (a)  This letter will constitute our entire agreement with regard to
               the subject matter hereof and will supersede any prior agreements
               or understandings with respect thereto, whether in writing or
               oral.

          (b)  This letter shall be governed by the law of the State of New
               Jersey.

          Please indicate your acceptance of the above by signing the enclosed
additional copy of this letter, which execution will evidence your agreement
with the terms set forth herein and therein, and returning it to the Company.

          This letter agreement supersedes any prior written or oral
understandings and agreements.

Sincerely,



By: /s/ Tony Scullion
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Name:  Tony Scullion
Title: Chief Executive Officer



ACCEPTED AND AGREED:



    /s/ Axel Unterbeck
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Date: 8/20/02
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