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                                                                   EXHIBIT 10.20


                          COLLABORATIVE DISCOVERY
                        AND LEAD OPTIMIZATION AGREEMENT


     This Collaborative Discovery and Lead Optimization Agreement (the
"Agreement") is made and effective as of February 11, 2000 (the "Effective
Date"), by and between 3-Dimensional Pharmaceuticals, Inc., a corporation having
its principal place of business at Eagleview Corporate Center, 665 Stockton
Drive, Suite 104, Exton, PA 19341, U.S.A. (" 3DP"), and DuPont Pharmaceuticals
Company (a wholly-owned subsidiary of E. I. DuPont de Nemours & Co. ("DuPont"))
having its principal place of business at Centre Road, Chestnut Run Plaza,
Building 721, Wilmington DE 19880 ("DPC"). 3DP and DPC may be referred to herein
as a "Party" or, collectively, as the "Parties".

     WHEREAS, 3DP is engaged in discovery research for a variety of biologically
active compounds and the development of technologies to facilitate such
research, and 3DP has patented systems for generating chemical compounds having
desired pharmaceutical properties;

     WHEREAS, DPC is engaged in research and development of human therapeutic
products;

     WHEREAS, 3DP and DPC desire to enter into a research and development
collaboration identify qualified lead compounds active against selected targets
and suitable for medicinal chemistry optimization that may be developed and
commercialized by DPC;

     NOW, THEREFORE, in consideration of the various promises and undertakings
set forth herein, the Parties agree as follows:


ARTICLE 1.   DEFINITIONS

     The terms in this Agreement with initial letters capitalized, whether used
in the singular or the plural, shall have the meaning set forth below or, if not
listed below, the meaning designated in places throughout this Agreement.

     1.1     "Active Compound" means a 3DP Compound or Derivative Compound that
has been formally selected by DPC for preclinical and/or clinical development.

     1.2     "Affiliate" means (i) any corporation or business entity of which
at least 50% of the securities or other ownership interests representing the
equity, the voting stock or general partnership interest are owned, controlled
or held, directly or indirectly, by 3DP or DPC; or (ii) any corporation or
business entity which, directly or indirectly, owns, controls or holds at least
50% of the securities or other ownership interests representing the equity, the
voting stock or, if applicable, the general partnership interest, of 3DP or DPC.

     1.3     "Agreement" means the present agreement including its Appendices.

     1.4     "Confidential Information" means all information that has or could
have commercial value or other utility in a Party's business, or the
unauthorized disclosure of which could be detrimental to the Party's interests,
including confidential information, inventions,
<PAGE>

know-how, data and materials relating to the Research Program or to the Licensed
Products, and shall include without limitation research, technical, clinical
development, manufacturing, marketing, financial, personnel and other business
information and plans, whether in oral, written, graphic or electronic form.

     1.5     "Custom Accessible Library" means any DirectedDiversity? Chemical
Library produced by 3DP using 3DP DirectedDiversity?  Technology and structure
activity data provided by DPC.

     1.6     "Combination Product" means a Licensed Product which includes one
or more active ingredients other than an Active Compound.

     1.7     "Derivative Compound" means any compound other than a 3DP Compound,
but which: [**]

     1.8     "DirectedDiversity? Chemical Library" means a computer-generated
library of compounds containing integrated structure-activity and synthesis
data.

     1.9     "DPC" means DuPont Pharmaceuticals Company as identified above.

     1.10    "DuPont" means E. I. DuPont de Nemours & Co. as identified above.

     1.11    "Effective Date" means the effective date of this Agreement as set
forth above.

     1.12    "Field" means [**]

     1.13    "Licensed Product" means any commercial product containing an
Active Compound.

     1.14    "First Commercial Sale" shall mean, with respect to a given
Licensed Product, the first sale for use or consumption by the public of such
Licensed Product in a country after all required approvals, including marketing
and pricing approvals, have been granted by the applicable governmental drug
regulatory agency of such country.

     1.15    "FTE" means a full time equivalent scientist (i.e., one full-time
or multiple part-time scientists aggregating to one full-time scientist)
employed by 3DP and assigned to work on the Research Program with such time and
effort to constitute one scientist working on the Research Program on a full
time basis consistent with normal business and scientific practice (at least 40
hours per week of dedicated effort; on an annual basis, at least 40 hours per
week of dedicated effort for at least 48 weeks per year). In no event, does an
FTE include a subcontractor.


** Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission. The omitted
portions have been filed separately with the Commission.

                                       2
<PAGE>

     1.16    "NDA" means an application for the final approval required for
authorization for marketing of a Licensed Product in a given country (including
applicable regulatory, marketing and pricing approval) in accordance with the
applicable laws and regulations of a given country. In the U.S., NDA means a New
Drug Application or its equivalent in the Food and Drug Administration or
successor agency.

     1.17    "Net Sales" means the aggregate gross invoiced sales price of
Licensed Product sold in the Territory by DPC, its Affiliates and any licensees
or sublicensees, to an independent third party, including but not limited to
distributors, in bona fide, arms-length transactions, after deduction of the
following items (to the extent actually incurred or reasonably estimated and
accrued and to the extent not already deducted in the amount invoiced): (i)
customary trade, quantity and case discounts, wholesaler-charge backs, or
rebates (including rebates to governmental agencies); (ii) customary credits or
allowances for rejection or return of previously sold Licensed Products; (iii)
any direct tax, duties, surcharges or government charge (other than an income
tax) levied on the sale, transportation or delivery of a Licensed Product and
borne by the seller thereof; (iv) retroactive price reductions; and (iv) any
charge for freight or insurance if separately stated.

     In the circumstance where all the active ingredients of a Combination
Product are also sold separately and in identical strengths to those contained
in the Combination Product, then the following shall apply:

     Net Sales shall be calculated as set forth above on the basis of the gross
invoice price of a Licensed Product containing the same weight of Active
Compound sold independently [ A ] divided by the sum of the gross invoice price
of each of the active ingredients contained in the Combination Product sold
independently [ B + A ], multiplied by the gross invoice price of the
Combination Product, as shown by the following formula:

     Net Sales =     [A]  x [gross invoice price of the Combination Product]
                   -------
                   [B + A]

     In the event the Active Compound and/or any of the other active ingredients
of a Combination Product are not sold separately in identical strengths to those
contained in the Combination Product, then the Parties agree to negotiate in
good faith the calculation of Net Sales with regard to such Combination Product
based upon the relative value of the active ingredients as determined by the
Parties hereto in good faith.

     1.18    "Patents" means all U. S. patent applications or issued patents,
including provisionals, divisionals, continuations, continuations-in-part,
reissues and extensions derived therefrom, such as patent term restorations,
supplementary protection certificates, etc., as well as all foreign patents and
foreign patent counterparts to the foregoing.

     1.19    "Qualified Lead Compound" means a 3DP Compound or a Derivative
Compound that satisfies the criteria established by the Research Steering
Committee.

     1.20    "Research Plan" means the detailed description of the research and
development activities of the Parties for particular Targets in the performance
of the Research Program. The

                                       3
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Research Plan shall be prepared by the RSC and shall be updated in writing
as changes are made to the Research Plan.

     1.21    "Research Program" means the collaborative discovery and
optimization activities of the Parties, as described in Article 2, that are
intended to lead to the discovery of small molecule Qualified Lead Compounds
that have an agreed upon level of activity against a Target and are suitable for
medicinal chemistry optimization and commercial development by DPC.

     1.22    "Research Program Patents" shall mean [**]

     1.23    "Research Steering Committee" or " RSC" means the committee to be
formed pursuant to Article 3 of this Agreement.

     1.24    "Target" means a [**]

     1.25    "Territory" means the entire world.

     1.26    "Third Party" means an individual, corporation or other entity
other than the Parties and their Affiliates.

     1.27    "3DP" means 3-Dimensional Pharmaceuticals, Inc. as identified
above.

     1.28    "3DP Accessible Library" means any DirectedDiversity?  Chemical
Library that is generated by 3DP outside of the Research Program.

     1.29    "3DP Compound" means any compound that is synthesized by 3DP during
the term of the Research Program and acts through a Target.

     1.30    "3DP DirectedDiversity? Technology" means 3DP Patents and
proprietary know-how that relate to generating and utilizing a
DirectedDiversity? Chemical Library, including but not limited to U.S. Patent
Nos. 5,463,564; 5,574,656; and 5,684,711 and 5,901,069. This term does not
include the SAR models as described in Article 2 of this Agreement.

     1.31    "3DP Patents" means any Patents owned or controlled by 3DP by
assignment, license or otherwise, which 3DP has the right to license or
sublicense to DPC, other than Research Program Patents.

     1.32    "Valid Claim" means a claim of a Patent that has not lapsed or
become abandoned or been declared invalid or unenforceable by a court or agency
of competent jurisdiction from which no appeal can be or has been taken.

**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

                                       4
<PAGE>

Article 2. RESEARCH PROGRAM

     2.1     General Project Description. The Parties contemplate that the
Research Program will include the following steps and activities:

             (a)    DPC will furnish to 3DP the structure and activity data on
                    chemical compounds screened against a Target, including both
                    compounds that are active ("Hits") and compounds that are
                    inactive against the Target.

             (b)    3DP will use its DirectedDiversity?  Technology to compute a
                    chemical descriptor matrix to describe and map the compounds
                    for which DPC provides data.  3DP also will develop a
                    Structure Activity Relationship (" SAR") model based on
                    this descriptor matrix for Hits.

             (c)    3DP will compare the SAR model with compounds in 3DP
                    Accessible Libraries, and 3DP will identify [**] compounds
                    to be synthesized by 3DP and supplied to DPC for testing.
                    3DP will supply between [**] milligrams of each such
                    compound in 96 deep well plates (about 80 compounds per
                    plate). [**]

             (d)    3DP will provide DPC with a secure internet based
                    communication channel to provide activity or other compound
                    related data to 3DP.

             (e)    3DP will develop an improved SAR model based on the testing
                    data provided by DPC.  This improved SAR will be used to
                    perform iterative rounds of selection and synthesis of
                    compounds from 3DP Accessible Libraries, and/or to develop
                    Custom Accessible Libraries from which compounds will be
                    selected and synthesized, and/or to perform preliminary
                    medicinal chemistry optimization and synthesis.  Such
                    compounds will be supplied to DPC for additional testing in
                    furtherance of the Research Program.

     2.2     Production of Qualified Lead Compounds. 3DP will iterate the steps
of the foregoing Section 2. 1 (e) until [**] Qualified Lead Compounds have been
identified for a Target.

     2.3     Production of Active Compounds. 3DP will chemically modify
Qualified Lead Compounds as may be appropriate with the objective of generating
compounds which will be selected as Active Compounds by DPC.

     2.4     Development of Active Compounds. DPC will conduct the preclinical
and clinical tests as it deems appropriate for the commercial development of
Active Compounds in the Field that are developed from Qualified Lead Compounds.


** Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

                                       5
<PAGE>

     2.5     Initial Term and Extension of Research Program. The initial term of
the Research Program shall run until December 31, 2001. DPC may extend the term
of the Research Program for up to 3 additional 1-year periods on an annual basis
by notifying 3DP in writing at least ninety (90) days prior to the end of the
initial term or any extended one-year term then in effect.

     2.6     Additional and Alternative Targets. DPC, through the Research
Steering Committee, shall have the option to bring forward a total of up to [**]
Targets at any one time or to propose changing Targets.

     2.7     Research Efforts. Each party shall use good faith commercially
reasonable and diligent efforts (as defined below) to perform its
responsibilities in the performance of the Research Program.  DPC will provide
funding to 3DP as set forth in Section 4.1 during the ten-n of the Research
Program to support qualified FTEs at 3DP, which funding by DPC shall be
contingent upon 3DP providing and retaining at least [**] such qualified FTEs
assigned to the performance of the Research Program.  As used herein, the term
"commercially reasonable and diligent efforts" will mean, unless the Parties
agree in writing otherwise, those efforts consistent with the exercise of
prudent scientific and business judgment in accordance with industry standards,
as applied to other programs of similar scientific and commercial potential.

     Throughout the term of the Research Program, including any extensions
thereof, 3DP shall assign the number of FTE qualified scientists specified in
the Research Plan to perform the work set forth in the Research Plan.  The
mixture of skills and levels of such FTEs shall be appropriate to the scientific
objectives of the Research Program and 3DP shall provide information about these
FTEs to the RSC upon request.  Unless the RSC agrees otherwise in writing, at
least 50% of such FTE support shall be Ph.D. level scientists.  The scientists
comprising such FTEs and their percentage of time devoted to working on the
Research Program shall be identified in Research Plan.  In the event that DPC
has reasonable concerns regarding any scientist assigned by 3DP to the Research
Program, such concerns shall be communicated to and addressed by the RSC.  The
Parties shall proceed diligently with the work set out in the Research Plan by
using their respective good faith commercially reasonable and diligent efforts.

     Other than the research funding provided by DPC to 3DP under Section 4.1
hereof, and except as otherwise specifically agreed in writing by 3DP and DPC,
each party shall be responsible for all costs and expenses it incurs in its
performance of the Research Program.

     2.8     Disclosure of Results; Reports. The results of all work performed
by the Parties as part of the Research Program shall be promptly disclosed to
the other Party as such results are obtained. The Parties will exchange at a
minimum quarterly written reports (with copies to the RSC) presenting a
meaningful summary of the work performed on the Research Program. In addition,
on reasonable request by DPC, 3DP will make presentations of its activities
under this Agreement to inform DPC of the details of the work done under this
Agreement.

**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

                                       6
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     Know-how and other information regarding the Research Program disclosed by
one Party to the other Party pursuant hereto may be used only in accordance with
the rights granted under this Agreement.  Within 30 days following the end of
each calendar quarter, the Parties shall each exchange and provide to the RSC a
written report summarizing in reasonable detail the work performed by it under
the Research Program during the preceding calendar quarter.

Article 3. RESEARCH PROGRAM GOVERNANCE

     3.1     Research Steering Committee.  3DP and DPC agree to establish a
Research Steering Committee, and shall each designate three (3) members selected
by their respective R&D management to form this Research Steering Committee.
The Research Steering Committee shall be responsible for:

             (a)    Adopting, reviewing and amending the Research Plan to
                    implement the Research Program, subject to DPC approval.
                    The Research Plan for the first Target agreed to by the
                    Parties is described in Appendix A.
                                            ----------

             (b)    Monitoring the progress of research in the Research Program.

             (c)    Reviewing initial Target and any subsequent Target
                    selection.

             (d)    Agreeing on and adopting criteria for the designation of
                    Qualified Lead Compounds.  As an example, the Parties
                    contemplate that to satisfy such criteria in the case of
                    Hits that inhibit a Target with an [**], a Qualified Lead
                    Compound would require a [**] relatively more selective
                    against a Target than against related molecules, and be
                    patentable.  The criteria for the designation of Qualified
                    Lead Compounds shall be set forth in the Research Plan.

             (e)    Selecting Qualified Lead Compounds to be advanced for
                    biological testing.

             (f)    Reviewing and approving publications and other public
                    disclosures related to the subject matter of the Research
                    Program.

     3.2     RSC Meetings. The RSC shall meet in-person or by teleconference on
a calendar quarter basis or more frequently as necessary as may be agreed upon,
with each party to bear all travel and related costs for its representatives.
Minutes of the meetings of the RSC will be generated and circulated to its
members within 2 weeks following the RSC meeting.

     3.3     RSC Decision-Making Process. Each member of the RSC shall have one
vote, and decisions by the RSC shall be made by a majority vote. The Parties
shall attempt to resolve any disagreement among members of the RSC within the
RSC based on the efficient achievement of the objectives of this Agreement. Any
disagreement which cannot be resolved by a majority vote of the RSC shall be
referred to the appropriate officers of 3DP and DPC for resolution as set forth
in Article 12. It is the intent of the Parties to resolve issues through the RSC
whenever possible and to refer issues to the officers of 3DP and DPC only when
resolution through the RSC cannot be achieved.


**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

                                       7
<PAGE>

     3.4     Management of Matters Outside the Jurisdiction of the Research
Steering Committee.  Matters outside the scope of the Research Program and
internal to each Party are not under the purview of the Research Steering
Committee.  Such matters include, but are not limited to the following: internal
personnel policies and programs, budgeting, finance, commercial and marketing
strategies, and business decisions. However, the Parties agree to communicate
with each other promptly on those matters which, while outside the scope of the
Research Program, nevertheless may reasonably be expected to influence the
conduct or term of the Research Program or the intended commercialization of any
Qualified Lead Compounds.

ARTICLE 4. FINANCIAL TERMS

     4.1     Technology Access and FTE Reimbursement Fees.

             [**] In the event that 3DP provides less than the number of FTEs as
             specified above in support of the Research Program, the foregoing
             payments will be reduced in proportion to the level of FTE support
             actually provided by 3DP in support of the Research Program. Such
             research funding shall be payable by DPC to 3DP in four quarterly
             installments during the term of the Research Program within 30 days
             of the start of the calendar quarter. Any payment for a portion of
             a quarterly period shall be made on a pro rata basis. Except as
             provided in this Section 4.1, or as may be agreed from time to time
             by the parties in writing, 3DP and DPC will each bear all of its
             own expenses incurred in connection with the Collaboration.
             Depending on the total number of Targets designated and the number
             of 3DP FTEs reasonably necessary to meet the objectives of this
             Agreement, DPC and 3DP shall negotiate in good faith with respect
             to additional compensation to 3DP in a form to be agreed upon by
             the Parties, such as a lump sum payment or support by DPC for
             additional FTEs at 3DP. The Parties agree that the rate of
             compensation per FTE year shall be indexed annually to the U.S.
             Consumer Price Index (CPI) and adjusted for payments beginning with
             the first quarter of the year 2001.

     4.2     Extended Term Fees.  The level of reimbursement for FTEs in any
extended term of the Research Program extending after December 31, 2002 shall be
negotiated in good faith by the Parties, and shall at least reflect any increase
to the FTE support level and any changes in the CPI in accordance with Section
 4. 1 (b).

     4.3     Fees for Early Termination of the Research Program. If DPC
terminates this Agreement without cause pursuant to Section 9.2 prior to the end
of the initial term or any extended term of the Research Program, it agrees to
pay to 3DP the balance of any financial support otherwise due for that term of
the Research Program.

     4.4     Milestone Payments.  DPC agrees to make milestone payments as set
forth below upon the first occurrence of each milestone event for each 3DP
Compound and Derivative Compound.  Subject to the conditions set forth below,
the milestone payments as set forth below shall be paid only one time for any
particular 3DP Compound or Derivative Compound (regardless, for example, of the
number of clinical trials conducted and NDA approvals obtained for that
particular 3DP Compound or Derivative Compound). The amounts set forth below
apply


**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

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to 3DP Compounds and the applicable payments due for Derivative Compounds shall
be [**] of the milestone payment amounts set forth below:

             [**]

     4.5     Royalty on Net Sales of Licensed Products.  DPC agrees to pay an
annual royalty based on Net Sales of Licensed Products.  Royalty payments shall
be due on December 31 of each calendar year in which Net Sales are generated.

             [**]

     4.6     Royalty Reduction.  The royalty amounts set forth above shall be
reduced by [**] on a country-by-country basis at any such time that there is no
Patent pending or in effect that claims a particular Licensed Product in such
country.  For purposes of this Section 4.6, the royalty otherwise due in such
country shall be decreased by [**].

     4.7     Royalty Period. The royalty payments set forth above shall be
payable for each Licensed Product on a product-by-product and country-by-country
basis from the time of First Commercial Sale of Licensed Product in such country
until the later of (i) [**] years from the time of First Commercial Sale of
Licensed Product in such country or (ii) until the last to expire patent
containing a Valid Claim providing marketing exclusivity with respect to such
Licensed Product.

     4.8     Royalty Conditions. The royalties under this Article shall be
subject to the following conditions:

                    (i)   that only one royalty shall be due with respect to the
                    same unit of Licensed Product;

                    (ii)  that no royalties shall be due upon the sale or other
                    transfer among DPC, its Affiliates or licensees, but in such
                    cases the royalty shall be due and calculated upon DPC's or
                    its Affiliate's or licensee's Net Sales of Licensed Product
                    to the first independent third party;

                    (iii) no royalties shall accrue on the disposition of
                    Licensed Product in reasonable quantities by DPC, its
                    Affiliates or licensees as part of an expanded access
                    program or as bona fide samples or as donations to non-
                    profit institutions or government agencies for non-
                    commercial purposes; and

                    (iv) notwithstanding the above royalty rates, upon DPC's
                    request, the parties agree to discuss in good faith a
                    reduction of such royalty rate in any given country in the
                    event the available patent protection materially decreases
                    the commercial viability of the Licensed Product under such
                    royalty rate.

     4.9     Third Party Patents. In the event that during the term of the
royalty obligation for a Licensed Product under this Article IV, a third party
shall control a patent or patents in any country covering the sale of a Licensed
Product, and in the reasonable judgment of DPC, it would


**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

                                       9
<PAGE>

be impractical or impossible for DPC (or its Affiliates or licensees or
sublicensees) to continue to sell the Licensed Product without obtaining a
royalty bearing license from such third party, then DPC shall be entitled to a
credit against the royalties due hereunder with respect to such country in an
amount equal to [**] of the royalty otherwise due under this Agreement, arising
from the sale of the Licensed Product in said country. However, the foregoing
royalty credit shall only be available when the total royalty obligation owed by
DPC (or its Affiliates or licensees or sublicensees) to unaffiliated third
parties exceeds [**] of Net Sales of Licensed Product.

     4.10    Mode of Payment. All payments to 3DP hereunder shall be made by
wire transfer of United States Dollars in the requisite amount to such bank
account as 3DP may from time to time designate by notice to DPC. Milestone
payments shall be made with in sixty days of occurrence of the relevant
milestone event and royalty payments for a given calendar year shall be made
with in sixty days following the end of the calendar year. Payments shall be
free and clear of any taxes (other than withholding and other taxes imposed on
3DP), fees or charges, to the extent applicable. For purposes of computing
royalty payments for Net Sales made outside of the United States, such royalties
shall be converted into U.S. Dollars, by applying the rate of exchange as used
by DPC's global accounting system which reflects the average exchange rate for
the applicable payment period.

     4.11    Records Retention. With respect to any products for which royalties
are due pursuant to Section 4.6, DPC and its Affiliates and any licensees or
sublicentees shall keep records, for two (2) years, of such Net Sales in
sufficient detail to confirm the accuracy of the royalty calculations hereunder.
At the request of 3DP, DPC shall permit an independent certified accountant of
nationally recognized standing appointed by 3DP and reasonably acceptable to
DPC, at reasonable times and upon reasonable notice, to examine these records
solely to the extent necessary to verify such calculations. Such investigation
shall be at the expense of 3DP unless it reveals a discrepancy in DPC's favor of
more than ten percent, in which event it shall be at DPC's expense.

     4.12    Taxes.  The Party receiving royalties and other payments under this
Agreement shall pay any and all taxes levied on account of such payment.  If any
taxes are required to be withheld by the paying Party, it shall: (a) deduct such
taxes from the remitting payment, (b) timely pay the taxes to the proper taxing
authority, and (c) send proof of payment to the other Party and certify its
receipt by the taxing authority within sixty (60) days following such payment.

Article 5. EXCLUSIVITY, OWNERSHIP OF ACCESSIBLE LIBRARIES AND LICENSE OF
RIGHTS

     5.1     Exclusivity. During the term of the Research Program and for a
period of 1 year thereafter 3DP shall work exclusively with DPC, and shall not
work independently of DPC, either alone or with any third party, with respect to
(i) the modeling, design, synthesis, screening and testing of compounds which
act through any Target, and (ii) the screening and testing of compounds in
assays to detect compounds which act through any Target.

     5.2     Ownership of 3DP Accessible Libraries and 3DP Patents; License
Grant to DPC Under 3DP Patents. 3DP shall own all 3DP Accessible Libraries. In
the case where any Qualified Lead Compound, Active Compound or Licensed Product
resulting from the Research


**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.

                                       10
<PAGE>

     Program that is developed by DPC is claimed in a 3DP Patent based on
research outside of the Research Program, 3DP hereby grants to DPC a fully paid
up, worldwide, exclusive license, with right to sublicense, in the Field under
such patent to develop, make, have made, use, sell, offer for sale, have sold,
import and have imported Licensed Products, provided that 3DP is not
contractually prohibited under a written agreement with a third party from
granting such an exclusive license. In the event that 3DP is so contractually
prohibited from granting such an exclusive license, 3DP shall grant to DPC as
broad a scope of license as it is permitted (for example, a non-exclusive
license) and 3DP shall use its reasonable best efforts to negotiate with such
third party to remove such contractual prohibition so as to allow 3DP to grant
DPC the foregoing exclusive license under such 3DP Patents.

     5.3     Unblocking License Grant to DPC. Subject to the limitation set
forth in Section 5.2 and subject to the other terms and conditions of this
Agreement, 3DP hereby grants to DPC a worldwide, nonexclusive license, with
right to sublicense, to develop, make, have made, use, sell, offer for sale,
have sold, import and have imported 3DP Compounds, Derivative Compounds, and
Licensed Products, under any 3DP patent rights which would otherwise be
infringed by DPC but for this license.

     5.4     Ownership of Custom Accessible Library Compounds.  DPC shall own
Custom Accessible Libraries and the compounds they contain that are produced in
the course of the Research Program.  However, DPC agrees to grant 3DP a fully
paid up, nonexclusive, worldwide license in order to use chemical process
methodologies developed for the synthesis of Custom Accessible Library compounds
for 3DP discovery programs.

     5.5     Grant-back of Rights to 3DP Outside of the Field After Termination
of the Research Program. [**]

     5.6     Non-assertion by DPC. [**]

Article 6. CONFIDENTIAL INFORMATION

     6.1     Confidentiality Obligations. The Parties agree that, for the term
of this Agreement and for ten (10) years thereafter, either Party that receives
Confidential Information (a "Receiving Party") from the other Party (a
"Disclosing Party") shall keep completely confidential and shall not publish or
otherwise disclose and shall not use for any purpose (except as expressly
permitted hereunder) any Confidential Information furnished to it by the
"Disclosing Party" pursuant to this Agreement (including without limitation,
know-how), except to the extent that it can be established by the Receiving
Party that such Confidential Information:

**Certain portions of this Exhibit have been ommitted based upon a request for
confidential treatment that has been filed with the Commission. The omitted
portions have been filed separately with the Commission.

                                       11
<PAGE>

             (a)    was already known to the Receiving Party, other than under
                    an obligation of confidentiality from the Disclosing Party;

             (b)    was generally available to the public or otherwise part of
                    the public domain at the time of its disclosure to the
                    Receiving Party;

             (c)    became generally available to the public or otherwise part
                    of the public domain after its disclosure and other than
                    through any act or omission of the Receiving Party in breach
                    of this Agreement;

             (d)    was subsequently lawfully disclosed to the Receiving Party
                    by a Third Party;

             (e)    can be shown by written records to have been independently
                    developed by the Receiving Party without reference to the
                    Confidential Information received from the Disclosing Party
                    and without breach of any of the provisions of this
                    Agreement; or

             (f)    the disclosing party has specifically agreed in writing that
                    the receiving party may disclose.

     The obligations of confidentiality and non-use set forth in this Section
6.1 shall also apply to biological material and chemical compounds and
associated information (including without limitation know-how) disclosed by one
Party to the other prior to or during the term of this Agreement; provided
however, that such obligation of confidentiality and non-use shall not apply
with respect to compounds which are assigned to DPC or exclusively licensed to
DPC by 3DP.

     6.2     Written Assurances and Permitted Uses of Confidential Information.

             (a)    Each Party shall inform its employees and consultants who
perform substantial work on the Research Program, of the obligations of
confidentiality specified in Section 6.1 and all such persons shall be bound by
the terms of confidentiality set forth therein.

             (b)    The Receiving Party may disclose Confidential Information to
the extent the Receiving Party is compelled to disclose such information by a
court or other tribunal of competent jurisdiction, provided however, that in
such case the Receiving Party shall immediately give notice to the Disclosing
Party so that the Disclosing Party may seek a protective order or other remedy
from said court or tribunal. In any event, the Receiving Party shall disclose
only that portion of the Confidential Information that, in the opinion of its
legal counsel, is legally required to be disclosed and will exercise reasonable
efforts to ensure that any such information so disclosed will be accorded
confidential treatment by said court or tribunal.

             (c)    To the extent it is reasonably necessary or appropriate to
fulfill its obligations and exercising its rights under this Agreement, DPC may
disclose Confidential Information to its Affiliates, licensees and sublicensees
on a need-to-know basis on condition that such Affiliates, licensees and parent
companies agree to keep the Confidential Information confidential for the same
time periods and to the same extent as DPC is required to keep the

                                       12
<PAGE>

Confidential Information confidential under this Agreement.

          (d)       DPC or its licensees and 3DP may disclose such Confidential
Information to government or other regulatory authorities to the extent that
such disclosure is reasonably necessary to obtain patents covering any 3DP
Compound, Derivative Compound or Product or authorizations to conduct clinical
trials with and to commercially market any Product.

          (e)       The existence and the terms and conditions of this
Agreement which the Parties have not specifically agreed to disclose pursuant to
this Section 6.2 shall be treated by each Party as Confidential Information of
the other Party.

          (f)       If a Party is required to make any disclosure of the other
Party's Confidential Information, it will give at least thirty (30) days
written, advance notice to the latter Party of such disclosure requirement. If a
Party is required to disclose Confidential Information to comply with applicable
laws or governmental regulations, including but not limited to submitting
information to tax authorities or to comply with any discovery or similar
request for production of documents in litigation or similar alternative dispute
resolution proceedings, such party may make such disclosure provided it gives
prompt notice to the other Party, and provided it makes all reasonable efforts
to comply with all administrative or other procedures or to establish a
reasonable protective or similar order under which the confidential nature of
the information will be maintained.

     6.3  Permitted Disclosures for Business Development Purposes.
Notwithstanding the foregoing, or any other provision in this Agreement to the
contrary, 3DP may describe the financial terms of this Agreement in confidence,
in connection with capital raising or financing activities, or in connection
with a potential acquisition of 3DP, provided however, that any such recipient
of such disclosure shall agree in writing to keep such terms confidential for
the same time periods and to the same extent as 3DP is required to keep
Confidential Information confidential under this Agreement. Furthermore, DPC
acknowledges that 3DP may be obligated to disclose terms of this Agreement and
make public a copy of this Agreement in the event it becomes a public company as
required by applicable U.S. law; provided however, that the terms and copy of
this Agreement shall be redacted such that the extent of any such disclosure
shall be limited to that which in the opinion of 3DP's legal counsel is legally
required to be disclosed.

Article 7. PATENTS AND INTELLECTUAL PROPERTY

     7.1  Title to Patents.

          (a)       Subject to the other provisions of this Agreement, all
                    Research Program Patents shall be owned by DPC, to the
                    extent that they claim: (1) Custom Accessible Libraries
                    synthesized by 3DP and based on SAR provided by DPC; (2)
                    Qualified Lead Compounds; (3) Active Compounds and (4)
                    Licensed Products. All other Research Program Patents shall
                    be individually or jointly owned, depending on the inventive
                    contributions of each Party. Inventorship will be determined
                    under U.S. patent law.

          (b)       In accordance with the grant of rights under this Agreement,
                    all employees and consultants who are inventors on any
                    patents arising

                                       13
<PAGE>

                    under work carried out under the Research Program shall
                    assign to such Party or Parties all inventions made by such
                    persons during the course of performing the Research
                    Program.

     7.2  Filing of Patent Applications and Expenses.

          (a)       DPC has the night but not the obligation to pursue and
                    maintain Research Program Patents that it owns, at its own
                    cost. 3DP has the right but not the obligation to pursue and
                    maintain Research Program Patents that it owns, at its own
                    cost.

          (b)       Where there is co-ownership of any Research Program Patents,
                    the Parties will decide who is in the best position to file
                    and pursue patent applications, and shall regularly provide
                    each other with copies of all filings and other material
                    submissions and correspondence with the patent offices, in
                    sufficient time to allow for review and comment.  The costs
                    of prosecuting and maintaining patent applications that are
                    jointly owned shall be shared equally by the Parties.

     7.3  Enforcement of Patents.

          (a)       If either Party considers that a Valid Claim of any of the
                    Research Program Patents claiming the manufacture, use or
                    sale of Active Compounds or Licensed Products is being
                    infringed by a Third Party, it shall notify the other Party
                    and provide it with any evidence of such infringement which
                    is reasonably available. DPC shall have the right but not
                    the obligation, at it own expense, to attempt to remove such
                    infringement by commercially appropriate steps, including a
                    lawsuit. If required by law, 3DP shall join such suit as a
                    party, at DPC's expense. In the event DPC fails to take
                    commercially appropriate steps with respect to such
                    infringement within six months following notice of such
                    infringement, 3DP shall have the night to do so at its
                    expense, provided that DPC shall not be required to enforce
                    such Research Program Patents against more than one entity
                    or in more than one country at any one time.

          (b)       Any amounts recovered by DPC pursuant to subsection (a),
                    above, whether by settlement or judgment shall be reported
                    as Net Sales for the purpose of calculating any applicable
                    royalties to 3DP, after deduction of DPC's reasonable
                    expenses in making such recovery. If 3DP enforces such
                    patents pursuant to subsection (a), then any amounts
                    recovered by 3DP shall be retained by 3DP.

          (c)       The Party not enforcing the Research Program Patents
                    pursuant to subsections (a) above, shall provide reasonable
                    assistance to the other Party, including providing access to
                    relevant documents and other evidence and making its
                    employees available, subject to the enforcing Party's
                    reimbursement of any out-of-pocket expenses incurred by the
                    other Party.

                                       14
<PAGE>

          (d)       If either Party considers that a Valid Claim of any of the
                    jointly owned Research Program Patents other than those
                    Research Program Patents covered by subsections (a) above,
                    is being infringed by a Third Party, it shall notify the
                    other Party and provide it with any evidence of such
                    infringement which is reasonably available. The Parties
                    agree to discuss in good faith the enforcement of any such
                    jointly owned Research Program Patents. If such Patents are
                    enforced by either Party, the Party not enforcing such
                    Research Program Patents shall provide reasonable assistance
                    to the other Party, including providing access to relevant
                    documents and other evidence and making its employees
                    available, subject to the enforcing Party's reimbursement of
                    any out-of-pocket expenses incurred by the other Party.

     7.4  Third Party Patent Rights.  If any warning letter or other notice of
infringement is received by a Party, or action, suit or proceeding is brought
against a Party alleging infringement of a patent of any Third Party in the
manufacture, use or sale of an Active Compound or Licensed Product or in the
conduct of the Research Program, the Parties shall promptly discuss and decide
the best way to respond.

Article 8. INDEMNIFICATION

     8.1  Indemnification by DPC. DPC shall indemnify, defend and hold 3DP and
its agents, employees and directors (the " 3DP Indemnitees") harmless from and
against any and all liability, damage, loss, cost or expense (including
reasonable attorneys' fees) arising out of Third Party claims or lawsuits
related to (a) DPC's performance of its obligations under this Agreement; or (b)
the manufacture, use or sale of Licensed Products by DPC and its Affiliates,
sublicensees, distributors and agents, except to the extent such claims or suits
result from the breach of any of the provisions of this Agreement, negligence or
willful misconduct of the 3DP Indemnitees. Upon the assertion of any such claim
or suit, the 3DP Indemnitees shall promptly notify DPC thereof and DPC shall
appoint counsel reasonably acceptable to the 3DP Indemnitees to represent the
3DP Indemnitees with respect to any claim or suit for which indemnification is
sought. The 3DP Indemnities shall not settle any such claim or suit without the
prior written consent of DPC, unless they shall have first waived their rights
to indemnification hereunder.

     8.2  Indemnification By 3DP.  3DP shall indemnify, defend and hold DPC and
its agents, employees and directors (the "DPC Indemnitees") harmless from and
against any and all liability, damage, loss, cost or expense (including
reasonable attorneys' fees) arising out of Third Party claims or lawsuits
related to 3DP's performance of its obligations under this Agreement, except to
the extent that such claims or suits result from the breach of any of the
provisions of this Agreement, negligence or willful misconduct of the DPC
Indemnitees. Upon the assertion of any such claim or suit, the DPC Indemnitees
shall promptly notify 3DP thereof and 3DP shall appoint counsel reasonably
acceptable to the 3DP Indemnitees to represent the DPC Indemnitees with respect
to any claim or suit for which indemnification is sought. The DPC Indemnitees
shall not settle any such claim or suit without the prior written consent of
3DP, unless they shall have first waived their rights to indemnification
hereunder.

Article 9. TERM AND TERMINATION

                                       15
<PAGE>

     9.1  Term.  This Agreement shall commence upon the Effective Date.  The
term of the Research Program shall expire on December 31, 2001 unless extended
as provided under Section 2.5.  This Agreement otherwise shall terminate upon
expiration of the last Research Program Patent owned by DPC that claims Active
Compounds or Licensed Products.

     9.2  Termination of the Research Program Without Cause.  DPC may terminate
the Research Program upon ninety (90) days advance written notice during the
initial or any extended term of the Research Program.  However, termination fees
may be due as provided in Section 4.3.

     9.3  Breach. The failure by a Party to comply with any of the material
obligations contained in this Agreement shall entitle the other Party to give
notice to have the default cured.  If such default is not cured within sixty
(60) days after the receipt of such notice, or diligent steps are not taken to
cure if by its nature such default could not be cured within sixty (60) days,
the notifying Party shall be entitled, without prejudice to any of its other
rights conferred on it by this Agreement, and in addition to any other remedies
that may be available to it, to terminate this Agreement, provided, however,
that such right to terminate shall be stayed in the event that, during such 60
day period, the Party alleged to have been in default shall have: (i) initiated
arbitration in accordance with Section 12. 1, below, with respect to the alleged
default, and (ii) diligently and in good faith cooperated in the prompt
resolution of such arbitration proceedings.

     9.4  No Waiver.  The right of a Party to terminate this Agreement, as
provided in Section 9.3, shall not be affected in any way by its waiver or
failure to take action with respect to any prior default.

     9.5  Insolvency or Bankruptcy.

          (a)       Either Party may, in addition to any other remedies
                    available by law or in equity, terminate this Agreement by
                    written notice to the other Party in the event the latter
                    Party shall have become insolvent or bankrupt, or shall have
                    an assignment for the benefit of its creditors, or there
                    shall have been appointed a trustee or receiver of the other
                    Party or for all or a substantial part of its property or
                    any case or proceeding shall have been commenced or other
                    action taken by or against the other Party in bankruptcy or
                    seeking reorganization, liquidation, dissolution, winding-
                    up, arrangement or readjustment of its debts or any other
                    relief under any bankruptcy, insolvency, reorganization or
                    other similar act or law of any jurisdiction now or
                    hereafter in effect, or there shall have been issued a
                    warrant of attachment, execution, distraint or similar
                    process against any substantial part of the property of the
                    other Party, and any such event shall have continued for 90
                    days undismissed, unbonded and undischarged.

          (b)       All rights and licenses granted under or pursuant to this
                    Agreement by DPC or 3DP are, and shall otherwise be deemed
                    to be, for purposes of-Section 365(n) of the U.S. Bankruptcy
                    Code, licenses of right to "Intellectual property" as
                    defined under Section 101 of the U.S. Bankruptcy Code.  The
                    Parties agree that the Parties as licensees of such

                                       16
<PAGE>

                    rights under this Agreement, shall retain and may fully
                    exercise all of their rights and elections under the U.S.
                    Bankruptcy Code. The Parties further agree that, in the
                    event of the commencement of a bankruptcy proceeding by or
                    against either Parties under the U.S. Bankruptcy Code, the
                    Parties hereto which is not a party to such proceeding shall
                    be entitled to a complete duplicate of (or complete access
                    to, as appropriate) any such intellectual property and all
                    embodiments of such intellectual property, and same, if not
                    already in their possession, shall be promptly delivered to
                    them (i) upon any such commencement of a bankruptcy
                    proceeding upon their written request therefor, unless the
                    Party subject to such proceedings elects to continue to
                    perform all of their obligations under this Agreement or
                    (ii) if not delivered under (i) above, upon the rejection of
                    this Agreement by or on behalf of the Party subject to such
                    proceeding upon written request therefor by a nonsubject
                    Party.

     9.6  Consequences of Termination.  Upon termination or expiration of the
Research Program portion of this Agreement, each Party shall promptly return all
records and materials relevant to the Research Program in its possession or
control containing the other Party's Confidential Information and to which the
former Party does not retain rights hereunder.  Upon termination of this
Agreement, all remaining records and materials in its possession or control
containing the other Party's Confidential Information and to which the former
Party does not retain rights hereunder shall promptly be returned.

     9.7  Survival of Obligations.  The termination or expiration of this
Agreement shall not relieve the Parties of any obligations accruing prior to
such termination, and any such termination shall be without prejudice to the
rights of either Party against the other. The provisions of Articles 4 - 8,
Sections 9.4, 9.6, 9.7 and Articles 12 and 13 shall survive any termination of
this Agreement.

Article 10. DEVELOPMENT, REGULATORY AND COMMERCIALIZATION RESPONSIBILITIES

     10.1 Development, Regulatory and Commercialization Responsibilities.  DPC
shall be responsible for all development, regulatory filings and related
submissions that are made in connection with the commercialization of Licensed
Products, and all commercialization activities with respect to Licensed
Products, and shall do so at DPC's sole discretion and expense.

Article 11. REPRESENTATIONS AND WARRANTIES

     11.1 Authority.  Each Party represents and warrants that it has the full
right, power and authority to execute, deliver and perform this Agreement.

     11.2 Commercially Reasonable Efforts.  DPC represents and warrants that it
will use good faith commercially reasonable and diligent efforts to develop and
to commercialize Active Compounds and Licensed Products, consistent with sound
business judgment.

     11.3 No Conflicts.  Each Party represents and warrants that the execution,
delivery and performance of this Agreement does not conflict with, or constitute
a breach or default under

                                       17
<PAGE>

any of its charter or organizational documents, any law, order, judgment or
governmental rule or regulation applicable to it, or any material agreement,
contract, commitment or instrument to which it is a party.

     11.4 No Existing Third Party Rights.  The Parties represent and warrant
that their obligations under this Agreement are not encumbered by any rights
granted by either Party to any Third Parties, which are or may be inconsistent
with the rights and licenses granted in this Agreement.

     11.5 Continuing Representations.  The representations and warranties of
each Party contained in this Article 11 shall survive the execution and delivery
of this Agreement and shall remain true and correct at all times during the term
of this Agreement with the same effect as if made on and as of such later date.

     11.6 No Warranty as to Commercial Success.  3DP offers no warranty that use
of the 3DP DirectedDiversity? Technology under this Agreement will result in the
discovery or the successful commercialization of a Licensed Product for use
against the Target in the Field.

Article 12. DISPUTE RESOLUTION

     12.1 Dispute Resolution.  Any dispute concerning or arising out of this
          ------------------
Agreement or concerning the existence or validity hereof, shall be determined by
the following procedure.

          (a)  Both Parties understand and appreciate that their long term
mutual interest will be best served by affecting a rapid and fair resolution of
any claims or disputes which may arise out of services performed under this
contract or from any dispute concerning the terms of this Agreement. Therefore,
both Parties agree to use their best efforts to resolve all such disputes as
rapidly as possible on a fair and equitable basis. Toward this end, both Parties
agree to develop and follow a process for presenting, rapidly assessing, and
settling claims on a fair and equitable basis which takes into account the
precise subject and nature of the dispute.

          (b)  If any dispute or claim arising under this Agreement cannot be
readily resolved by the Parties pursuant to the process described above, then
the Parties agree to refer the matter to a panel consisting of the Chief
Executive Officer ("CEO") of each Party or their designees for review and a non-
binding resolution.  A copy of the terms of this Agreement, agreed upon facts
(and areas of disagreement), and concise summary of the basis for each side's
contentions will be provided to both such CEOs or their designees who shall
review the same, confer, and attempt to reach a mutual resolution of the issue.

          (c)  If the matter has not been resolved utilizing the foregoing
process, and the Parties are unwilling to accept the non-binding decision of the
indicated panel, either or both Parties may elect to pursue definitive
resolution through binding arbitration, which the Parties agree to accept in
lieu of litigation or other legally available remedies (with the exception of
injunctive relief where such relief is necessary to protect a Party from
irreparable harm pending the outcome of any such arbitration proceeding).
Binding arbitration shall be settled in accordance with the Rules of
Conciliation and Arbitration of the International Chamber of Commerce by a panel
of three arbitrators chosen in accordance with these Rules.  This Agreement
shall be governed by and construed in accordance with the substantive laws of
the

                                       18
<PAGE>

State of Delaware without regard to the conflicts of laws provisions of
Delaware. The arbitration will be held in Wilmington, Delaware. Judgment upon
the award rendered may be entered in any court having jurisdiction and the
Parties hereby consent to the said jurisdiction and venue, and further
irrevocably waive any objection which either Party may have now or hereafter to
the laying of venue of any proceedings in said courts and to any claim that such
proceedings have been brought in an inconvenient forum, and further irrevocably
agree that a judgment or order in any such proceeding shall be conclusive and
binding upon the Parties and may be enforced in the courts of any other
jurisdiction.

Article 13. MISCELLANEOUS PROVISIONS

     13.1 Entire Agreement of the Parties.  This Agreement and its Appendices
constitute and contain the entire understanding and agreement of the Parties
respecting the subject matter of this Agreement and cancels and supersedes any
all prior negotiations, correspondence, understandings and agreements between
the Parties, whether oral or written, regarding such subject matter.

     13.2 Further Actions.  Each Party agrees to execute, acknowledge and
deliver such further instruments and to do all such other acts as may be
necessary or appropriate in order to carry out the purposes and intent of this
Agreement.

     13.3 Binding Effect.  This Agreement and the rights granted herein shall be
binding upon and shall inure to the benefit of 3DP, DPC and their successors and
permitted assigns.

     13.4 Assignment.  This Agreement may be assigned by either Party in
connection with the sale or transfer of substantially all of its assets that
relate to this Agreement, or in the event of its merger or consolidation or
change of control or similar transaction.  Any permitted assignee shall assume
all obligations of its assignor under this Agreement.  If 3DP acquires, is
acquired by, merges with or otherwise combines with a company that has
substantial activities in the Field and is a significant competitor of DPC, DPC
may require 3DP to take reasonable actions necessary to ensure that any of DPC's
Confidential Information, trade secrets or proprietary information is not
disclosed to personnel within such company directly involved in such competitive
activities.

     13.5 No Implied Licenses.  No rights to any Patents, know-how or technical
information, or other intellectual property rights, other than as explicitly
identified herein, are granted or deemed granted by this Agreement.  No right,
expressed or implied, is granted by this Agreement to a Party to use in any
manner the name or any other trade name or trademark of the other Party in
connection with the performance of this Agreement.

     13.6 No Waiver.  No waiver, modification or amendment of any provision of
this Agreement shall be valid or effective unless made in writing and signed by
a duly authorized officer of each Party.  The failure of either Party to assert
a right hereunder or to insist upon compliance with any term or condition of
this Agreement shall not constitute a waiver of that right or excuse a similar
subsequent failure to perform any such term or condition.

     13.7 Force Majeure.  The failure of a Party to perform any obligation under
this Agreement by reason of acts of God, acts of governments, riots, wars,
strikes, accidents or

                                       19
<PAGE>

deficiencies in materials or transportation or other causes of a similar
magnitude beyond its control shall not be deemed to be a breach of this
Agreement.

     13.8 Independent Contractors.  Both Parties are independent contractors
under this Agreement.  Nothing contained in this Agreement is intended nor is to
be construed so as to constitute 3DP or DPC as partners or joint venturers with
respect to this Agreement.  Neither Party shall have any express or implied
right or authority to assume or create any obligations on behalf of or in the
name of the other Party or to bind the other Party to any other contract,
agreement, or undertaking with any Third Party.

     13.9 Notices and Deliveries.  Any formal notices, request, delivery,
approval or consent required or permitted to be given under this Agreement shall
be in writing and shall be deemed to have been sufficiently given when it is
received, whether delivered in person, transmitted by facsimile with
contemporaneous confirmation, or delivery by registered letter (or its
equivalent) or delivery by certified overnight courier service, to the Party to
which it is directed at its address shown below or such other address as such
Party shall have last given by notice to the other Parties.

                         If to DPC:


                         Vice President, Product Planning and Acquisitions
                         DuPont Pharmaceuticals Company
                         974 Centre Road, Chestnut Run Plaza
                         Wilmington, DE 19805
                         Fax: 302-992-3040

                         with a copy to:
                         Associate General Counsel
                         Legal Division
                         DuPont Pharmaceuticals Company
                         974 Centre Road, Chestnut Run Plaza, WR1028 Wilmington,
                         DE 19805
                         Fax: 302-992-3999

                         If to 3DP:

                         3-Dimensional Pharmaceuticals, Inc.
                         Eagleview Corporate Center
                         665 Stockton Drive, Suite 104
                         Exton, PA 10341

                         ATTN: Chief Executive Officer with a copy to:

                                       20
<PAGE>

                         Morgan, Lewis & Bockius LLP
                         1701 Market Street
                         Philadelphia, PA 19103

                         ATTN: David R. King, Esq.

     13.10     Public Announcements.  The Parties shall consult with each other
and reach mutual written agreement before making any public announcement
concerning this Agreement or its subject matter. A joint press release to
announce the signing of this Agreement is attached as Appendix B to this
                                                      ----------
Agreement, and the Parties agrees to coordinate the dissemination of this press
release. Notwithstanding the foregoing, the Parties may disclose the existence
and general nature of this Agreement and may make disclosures for purposes of
satisfying legal and regulatory requirements in accordance with Article 6;
however, neither Party shall use the name of the other Party for promotional
purposes.

     13.11     Headings.  The captions to the sections and articles in this
Agreement are not a part of this Agreement, and are included merely for
convenience of reference only and shall not affect its meaning or
interpretation.

     13.12     Severability.  If any provision of this Agreement becomes or is
declared by a court of competent jurisdiction to be illegal, unenforceable or
void, this Agreement shall continue in full force and effect without said
provision, so long as the Agreement, taking into account said voided
provision(s), continues to provide the Parties with the same practical economic
benefits as the Agreement containing said voided provision(s) did on the date of
this Agreement.   If, after taking into account said voided provision(s), the
Parties are unable to realize the practical economic benefit contemplated on the
date of this Agreement, the Parties shall negotiate in good faith to amend this
Agreement to reestablish the practical economic benefit provided the Parties on
the date of this Agreement.

     13.13     No Consequential Damages.  IN NO EVENT SHALL EITHER PARTY OR ANY
OF ITS RESPECTIVE AFFILIATES BE LIABLE TO THE OTHER PARTY OR ANY OF ITS
AFFILIATES FOR SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES, WHETHER
IN CONTRACT, WARRANTY, TORT, NEGLIGENCE, STRICT LIABILITY OR OTHER WISE,
INCLUDING, BUT NOT LIMITED TO, LOSS OF PROFITS OR REVENUE, OR CLAIMS OF
CUSTOMERS OF ANY OF THEM OR OTHER THIRD PARTIES FOR SUCH OR OTHER DAMAGES.

     13.14     Applicable Law.  This Agreement shall be governed by and
interpreted in accordance with the laws of the State of Delaware without
reference to its conflicts of laws provisions.

     13.15     Advice of Counsel.  DPC and 3DP have each consulted with counsel
of their choice regarding this Agreement, and each acknowledges and agrees that
this Agreement shall not be deemed to have been drafted by one party or another
and will be construed accordingly.

     13.16     Counterparts.  This Agreement may be executed in counterparts, or
facsimile versions, each of which shall be deemed to be an original, and both of
which together shall be deemed to be one and the same agreement.

                                       21
<PAGE>

     IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed
by their respective duly authorized officers as of the day and year first above
written, each copy of which shall for all purposes be deemed to be an original.


<TABLE>
<CAPTION>
3 DIMENSIONAL                              DUPONT PHARMACEUTICALS
PHARMACEUTICALS, INC.                      COMPANY
<S>                                        <C>

By: /s/  David C. U'Prichard               By: /s/ Paul A. Friedman, M.D.
   ------------------------------             ---------------------------
Name:  David C. U'Prichard, Ph.D.          Name:   Paul A. Friedman, M.D.

Title:  Chief Executive Officer            Title:  President, DuPont Pharmaceuticals
                                                   Research Laboratories
</TABLE>

                                       22
<PAGE>

Appendix A [**]












**Certain portions of this Exhibit have been omitted based upon a request for
confidential treatment that has been filed with the Commission.  The omitted
portions have been filed separately with the Commission.


<PAGE>

                       Appendix B - Joint Press Release


FOR IMMEDIATE RELEASE

For 3DP, Contact:                               For DuPont, Contact:
--------------------------------------------------------------------------------

Business
Michael J. Wassil                               Thomas R. Barry
Chief Financial Officer                         302-992-5020
610-458-6073

Media
Jerry Parrott
Jerry Parrott & Associates
703-757-0950

                   DuPont and 3-Dimensional Pharmaceuticals
                     Announce Drug Discovery Collaboration

  - DuPont also Licenses 3DP's DirectedDiversity(R) Drug Discovery Patents -


Exton, PA and Wilmington, DE - February XX, 2000 - DuPont Pharmaceuticals
Company, a wholly-owned independent subsidiary of DuPont (NYSE: DD), and 3-
Dimensional Pharmaceuticals, Inc. (3DP) today announced a strategic
collaboration in which 3DP will use its proprietary DirectedDiversity(R)
technology to assist DuPont Pharmaceuticals in the discovery of innovative new
drugs for specific biological targets.

3DP will apply its iterative drug discovery process to generate custom
combinatorial chemistry libraries based on molecules and information provided by
DuPont Pharmaceuticals and will optimize those molecules into preclinical drug
candidates. DuPont Pharmaceuticals will be responsible for preclinical and
clinical development, marketing and sales of the resulting products.

For the initial target, 3DP will receive payments of up to $9 million, including
an up-front technology access fee, research and development funding and
milestone payments. 3DP will also receive royalties on sales of resulting
products and will be eligible to receive additional payments if more than one
target is selected to be included in the collaboration.

The parties also announced an additional agreement in which DuPont
Pharmaceuticals will obtain a nonexclusive license to 3DP's proprietary
DirectedDiversity drug discovery patents. Under
<PAGE>

the license agreement, DuPont Pharmaceuticals will receive a non-exclusive
license to 3DP's DirectedDiversity patents in support of DuPont Pharmaceuticals
internal research programs, and will pay an annual Site License fee for each
DuPont Pharmaceuticals facility using the technology,

"DuPont Pharmaceuticals is committed to aggressive exploration and use of
leading-edge discovery technologies to speed the process of research and
development and to improve the quality of new drugs entering clinical trials,"
said Paul Friedman, M.D., President of DuPont Pharmaceuticals Research
Laboratories.

David C. U'Prichard, Ph.D., Chief Executive Officer of 3-Dimensional
Pharmaceuticals, noted that 3DP's technology platform allows the company to
discover and refine drugs against a wide range of molecular targets more quickly
than conventional approaches. "DuPont is one of the great pioneering research
based companies, and we are particularly pleased with this important recognition
of 3DP's proprietary DirectedDiversity drug discovery process.  Our scientists
look forward with great anticipation to working with their colleagues at DuPont
Pharmaceuticals," he said. "We are confident that the collaboration we are
announcing today will prove productive for both parties."

DirectedDiversity(R) Chemi-Informatic Technology uses proprietary computer
algorithms to design, select and iteratively refine combinatorial libraries of
novel, small-molecule drugs based on screening "hits" obtained from 3DP or other
screening libraries, target-protein 3D structures, or pharmacophore models
derived from lead compounds.

To prime the discovery process, 3DP has synthesized DirectedDiversity(R)
Screening Libraries totaling more than 200,000 individually synthesized drug-
like compounds. These compounds represent proven pharmacophore classes and
constitute an optimally diverse sampling of the DirectedDiversity(R) Accessible
Compound Libraries, which now total more than 1.5 billion compounds, each of
which is available for on-demand synthesis using parallel synthesis technology.

DirectedDiversity(R) is a major component of 3DP's DiscoverWorks(TM), which
provides a uniquely integrated platform for the high-throughput synthesis,
screening, and optimization of chemical compounds. DiscoverWorks(TM) can be
applied flexibly to a wide range of molecular targets
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identified through genome sequencing efforts -even in situations where the
target's biological function is ambiguous or unknown. DiscoverWorks(R) enhances
the efficiency of conventional drug discovery, making the process more rapid and
reliable.

Earlier this year, 30P received the fourth in a series of patents covering its
DirectedDiversity(R) process.  DirectedDiversity(R) controls and manages the
overall information flow for combinatorial drug discovery and provides the
computational tools needed to optimize drug properties rapidly using parallel
automated chemical synthesis. 3DP has a flexible licensing program available to
those companies interested in obtaining licenses to its DirectedDiversity(R)
patent portfolio.

Based in Wilmington, Delaware, DuPont Pharmaceuticals is a worldwide business
that focuses on research, development and delivery of pharmaceuticals to treat
unmet medical needs in the fight against HIV, cardiovascular disease, central
nervous system disorders, cancer and inflammatory diseases.  The company also is
a leader in medical imaging.

DuPont is a science company, delivering science-based solutions that make a
difference in people's lives in food and nutrition, health care, apparel, home
and construction, electronics, and transportation.  Founded in 1802, the company
operates in 65 countries and has 97,000 employees.

3-Dimensional Pharmaceuticals, Inc. (http://www.3dp.com) is a leading innovator
in drug discovery.   The company has developed a proprietary technology platform
known as DiscoverWorks, which uniquely integrates structure-based drug design,
combinatorial chemistry and high-throughput screening.  DiscoverWorks reduces
discovery costs, increases the rate of success and enhances the ultimate
commercial value of a drug development pipeline.  3DP is using its proprietary
technology both in collaboration with other companies and in its own research
programs, which currently target orally active small-molecule pharmaceuticals to
treat cardiovascular disease and cancer.