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                                                                   EXHIBIT 10.62



                            AMENDED PROMISSORY NOTE


$48,000.00                                                     February 24, 1997
                                                     As Amended November 8, 1998
                                                           San Diego, California


         VICENTE ANIDO, JR., an individual resident of the State of California
("Obligor"), for value received, hereby promises to pay to the order of
COMBICHEM, INC., a Delaware corporation, or holder ("Payee"), in lawful money of
the United States at 9050 Camino Santa Fe, San Diego, California 92121, the
principal sum of Forty-Eight Thousand Dollars ($48,000.00).

        Unpaid principal of this Note shall bear no interest.

        All unpaid principal under this Note shall be due and payable on the
earlier of (a) February 23, 2002; (b) the expiration of the 60-day period
following the date the Obligor ceases for any reason to remain in the Service of
Payee (as defined in that certain Restricted Stock Purchase Agreement dated
February 24, 1997 between Obligor and Payee); or (c) the date on which Payee
completes the consummation of any corporate transaction in which (i) more than
fifty percent (50%) of the outstanding shares of common stock of Payee are
acquired by a single purchaser or by a group of purchasers acting in concert in
a merger or any other transaction and Obligor receives cash or publicly traded
securities in connection therewith; or (ii) all or substantially all of the
assets of Payee are acquired by a single purchaser or a group of purchasers
acting in concert and Obligor receives cash or publicly traded securities in
connection therewith.

        Nothing in this Note shall confer upon the Obligor any right to continue
in the Service of Payee (or its successors or subsidiaries) for any period of
specific duration.

        Upon payment in full of all principal payable hereunder, this Note shall
be surrendered to Obligor for cancellation.

        This Note may be transferred only upon surrender of the original Note
for registration of transfer, duly endorsed, or accompanied by a duly executed
written instrument of transfer in form satisfactory to Obligor. Thereupon, a new
note for like principal amount and interest will be issued to, and registered in
the name of, the transferee. Principal is payable only to the registered holder
of this Note.

        Obligor waives presentment, demand for performance, notice of
nonperformance, protest, notice of protest, and notice of dishonor. No delay on
the part of Payee in exercising any right hereunder shall operate as a waiver of
such right under this Note. This Note is being delivered in and shall be
construed in accordance with the laws of the State of California.
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        If the indebtedness represented by this Note or any part thereof is
collected at law or in equity or in bankruptcy, receivership or other judicial
proceedings or if this Note is placed in the hands of attorneys for collection
after default, Obligor agrees to pay, in addition to the principal and interest
payable hereon, reasonable attorneys' fees and costs incurred by Payee.

        Any payment shall be deemed made upon receipt by Payee.

        This Note is the Note referred to in that certain Pledge Agreement
("Pledge Agreement") dated February 24, 1997 between Obligor and Payee, as
amended, and is subject to the terms thereof. The Pledge Agreement, among other
things, contains provisions for acceleration of the maturity of this Note upon
the happening of any one or more of the stated "Events of Default" set forth
therein. OBLIGOR UNDERSTANDS THAT THIS IS A FULL RECOURSE PROMISSORY NOTE AND
THAT PAYEE MAY, AT ITS OPTION, PROCEED AGAINST ASSETS OF THE UNDERSIGNED OTHER
THAN ANY COLLATERAL UNDER THE PLEDGE AGREEMENT IN THE EVENT OF DEFAULT. OBLIGOR
ACKNOWLEDGES AND UNDERSTANDS THAT THE RULE 144 HOLDING PERIOD MAY BE TOLLED WITH
RESPECT TO ANY COMMON STOCK PLEDGED PURSUANT TO THE PLEDGE AGREEMENT.

        Obligor acknowledges and agrees that he has been provided the
opportunity and encouraged to consult with counsel of Obligor's own choosing
with respect to this Agreement, and that Brobeck, Phleger & Harrison LLP solely
represents the interests of the Payee.

        IN WITNESS WHEREOF, Obligor has duly executed this Note, as of the date
first above written.



                                             /s/  Vicente Anido, Jr.
                                           -------------------------------------
                                           Vicente Anido, Jr.



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