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                                                                   Exhibit 10.14

[MEMORY LOGO]


MEMORY PHARMACEUTICALS CORP.
100 Philips Parkway
Montvale, New Jersey 07645
Phone: (201) 802-7102
Fax: (201) 802-7190
www.memorypharma.com


March 4, 2002

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

Dear Axel:

     We are writing to you in connection with the proposed sale of Series D
Preferred Stock (the "Series D Stock") of Memory Pharmaceuticals Corp. (the
"Company") pursuant to a Preferred Stock Purchase Agreement, dated March 4, 2002
(the "Purchase Agreement"), and the letter agreement of employment, effective
January 5, 1998, as amended by that certain amendment dated July 1, 1999 between
the Company and you, the compensation portion of which was amended by the
Compensation Committee of the Board of Directors of the Company on June 4, 2001
(the "Employment Compensation Package"). In connection with the Proposed Sale,
we wish to clarify the following items.

     First, the sale by the Company of any shares of Series D Stock in excess of
an aggregate of $40 million of gross proceeds shall not be included in the
Company's fully diluted shares of common stock ("Common Stock") for purposes of
computing the number of additional shares of Common Stock to be covered by stock
options awarded by the Company to you to enable you to maintain your ownership
percentage on a fully diluted basis at four percent (4%) as set forth in the
Employment Compensation Package (the "Percentage Maintenance Provision").

     Second, the provisions of said Percentage Maintenance Provision will cease
to have effect for any sale by the Company of Common Stock or securities
convertible or exchangeable into Common Stock subsequent to the sale by the
Company of the Series D Stock pursuant to the Purchase Agreement.

     Third, any increase in the Company's fully diluted shares of Common Stock
caused by an increase, if any, in the number of shares of Series D Stock
pursuant to Section 1.4 of the Purchase Agreement shall not be included in the
Company's fully diluted shares of Common Stock for purposes of applying the
provisions of said Percentage Maintenance Provision. Section 1.4 of the Purchase
Agreement reads as follows: "If a Clinical Trial Event (define below) has not
occurred by 5:00 P.M. (New York time) on March 4, 2003, then the purchase price
for the Series D Shares set forth in Section 1.2 of this Agreement shall be
adjusted to One Dollar Seventy-five Cents ($1.75) through the immediate issuance
to each holder of Series D Shares of additional Series D Shares equal to the
product of (i) the number of Series D Shares then held by such holder by (ii)
0.228571 (the quotient of $.40 divided by $1.75), provided that no fractional
shares of Series D Shares shall be issued upon conversion of any shares of
Preferred Stock and in lieu of any fractional shares of Series D Shares to which
such




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Dr. Axel Unterbeck
March 4, 2002
Page 2



holder would otherwise be entitled, the Company shall pay cash equal to such
fractional shares multiplied by One Dollar Seventy-five Cents $1.75." Section
6.1 of the Purchase Agreement reads as follows in relevant part: "'Clinical
Trial Event' shall mean the commencement of a Phase I clinical trial of a
product candidate to which the Company owns or otherwise has been licensed
commercialization rights and which Phase I clinical trial has been designed in
such a way and is occurring in such venue to allow, if such Phase I clinical
trial is successful, for submission of the results of such Phase I clinical
trial to the United States Food and Drug Administration for the purpose of
commencing a Phase IIa clinical trial of such product candidate."

     Except for the items expressly stated in this letter agreement, this letter
agreement does not amend any other terms or conditions in the Employment
Compensation Package.

     Please indicate your agreement with the above items by executing a
counterpart of this letter agreement in the location provided below for your
signature and returning it to the Company. We appreciate your assistance.


                                   Very truly yours,

                                   THE BOARD OF DIRECTORS OF
                                   MEMORY PHARMACEUTICALS CORP.


                                   By:  /s/ Joanne Leonard
                                      ------------------------------------------
                                   Name:  Joanne Leonard
                                   Title: Secretary to the Board of Directors



     ACCEPTED AND AGREED, as of the
     date first above written:



     /s/ Dr. Axel Unterbeck
     -------------------------------
     Dr. Axel Unterbeck