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                                                                   EXHIBIT 10.43


LOAN AGREEMENT


between Novartis International AG
Schwarzwaldallee 215, 4058 Basel,
represented by the Novartis Venture Fund                                 Lender

and Discovery Technologies AG
Gewerbestrasse 16, 4123 Allschwil                                      Borrower

and Discovery Partners International Inc.
9640 Towne Centre Drive, San Diego, CA 92121 USA                      Guarantor



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1.      The lender grants a loan to the borrower in the amount of CHF 2'600'000.
        The loan is given to finance the development of technologies for the
        discovery and design of novel bio-active compounds for the
        pharmaceutical and agrochemical industry, in particular for the
        high-through-put-screening (HTS).

2.      The loan bears interest at an annual rate of 5%.

3.      The loan is granted for a fixed period of eighteen months, i.e. until
        June 30, 2001.

4.      The loan must be used for the purposes mentioned in section 1. The
        Novartis Venture Fund will be regularly informed during the loan period.
        The borrower will report semiannually. The half-year (if available) and
        the annual report will be submitted, and additional information will be
        given on special request of the lender.

5.      In case of substantial deviations of the annual budget or the business
        activity from the business plan as submitted to the Novartis Venture
        Fund, the lender must be informed immediately.

6.      An extraordinary termination with a termination period of six weeks by
        the Novartis Venture Fund is only possible if the funds granted
        according to this agreement are not used for the purposes mentioned in
        section 1.

7.      A termination by the borrower is possible at any time. In case of
        partial termination only amounts of at least CHF 500'000 can be
        terminated and repaid.



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8.      This loan agreement replaces the loan agreement between the borrower and
        the Novartis Venture Fund (Novartis AG), dated May 30/June 2, 1997,
        which referred to a junior debt between the parties. The new loan
        according to this agreement is not junior and ranks pari passu with all
        other debt of the borrower.

9.      The amount of the loan of CHF 2'600'000 has been transferred to the
        lender according to the loan agreement mentioned in section 8 above.

10.     The borrower and the Novartis Venture Fund are also parties to an
        agreement on the creation of non-voting shares (participation
        certificates) and options. The borrower agrees to the immediate
        termination of that agreement and waves all rights according to that
        agreement.

11.     The Novartis Venture Fund has granted a warranty of CHF 1'000'000 for
        the borrower in favour of Basler Kantonalbank. This warranty expires on
        December 31, 1999 and the original warranty declaration will be handed
        over to the Novartis Venture Fund.

12.     The loan according to this agreement will be secured by a guarantee from
        Discovery Partners International Inc., the parent company of Discovery
        Technologies AG. Discovery Partners International Inc. will sign a
        guarantee declaration to that effect.

13.     This agreement shall be construed and interpreted according to the laws
        of Switzerland. Exclusive place of jurisdiction shall be Basel
        (Switzerland).




Basel,  23.12.99                               Allschwil,  23. December 1999
Novartis International AG                      Discovery Technologies AG


/s/ illegible                                  /s/ illegible


                                               /s/ illegible






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