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FOR IMMEDIATE RELEASE

CONTACT:
Sue Rodney
Manager, Investor Relations
Pharmacopeia, Inc.
(609) 452-3600


              PHARMACOPEIA ANNOUNCES AGREEMENT TO PURCHASE SOFTWARE
                      BUSINESS FROM OXFORD MOLECULAR GROUP

    -PHARMACOPEIA TO STRENGTHEN CHEMINFORMATICS POSITION AND TO GAIN INDUSTRY
              LEADING BIOINFORMATICS POSITION THROUGH GCG PRODUCTS-

Princeton, New Jersey and Oxford, England, August 9, 2000 - Pharmacopeia, Inc.
(Nasdaq: PCOP) and Oxford Molecular Group Plc ("OMG") (London: OMG) today
announced that they have signed a definitive agreement pursuant to which
Pharmacopeia will acquire OMG's software subsidiaries subject to OMG shareholder
approval. Once completed, this acquisition will provide Pharmacopeia with three
key assets: an industry leading position in the large and growing field of
bioinformatics, a broad line of cheminformatics products that complement
Pharmacopeia's existing chemical database tools from Synopsys Scientific
Systems, and a group of more than 120 talented employees, many of whom are
highly skilled scientific software developers.

OMG's software business, which generated revenues from continuing products of
approximately $15 million in 1999, designs and markets bioinformatics and
cheminformatics products for the pharmaceutical, biotechnology and chemical
industries. OMG's GCG product line gives researchers the power to capture,
manage, analyze, compare, and mine the huge volumes of genetic data created in
the search for novel therapeutic targets. The planned acquisition will augment
Pharmacopeia's existing suite of products with state-of-the-art bioinformatics
solutions that allow researchers to analyze DNA and protein sequence data. OMG's
bioinformatics solutions range from a single user desktop to enterprise-wide
server licensing and include well-known products such as the Wisconsin
Package-TM-.

The planned acquisition will also provide Pharmacopeia with cheminformatics
solutions that enable multidisciplinary research teams to capture, analyze and
communicate the increasing volumes of biological and chemical data created in
the search for new lead compounds and drug candidates. These products will
complement Pharmacopeia's existing cheminformatics products available through
Synopsys Scientific Systems. OMG cheminformatics products include the RS(3)
packages.

"The acquisition of Oxford Molecular's software business is strategically very
significant for

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Pharmacopeia to Acquire Software Business From OMG
August 9, 2000
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Pharmacopeia," said Joseph A. Mollica, Pharmacopeia's Chairman,
President and CEO. "We believe their bioinformatics products are unmatched in
quality and scientific utility. They serve an increasingly important function as
efforts continue to sequence and understand the human genome. Two especially
exciting areas of complementarity of expertise and product offerings are
functional genomics and proteomics, where GCG's sequence analysis strength can
be combined with our strength in assigning protein structure and its subsequent
function. In addition, the critical mass we will achieve from OMG's
cheminformatics products will benefit our customers as they seek to leverage the
important chemical data emerging from today's drug discovery efforts. This
acquisition should serve to fuel Pharmacopeia's continued growth."

"As we've stated in the past," continued Dr. Mollica, "our goal is to provide a
broad spectrum of integrated modeling, simulation, cheminformatics, and
bioinformatics products and services that help our customers accelerate drug
discovery and chemical development. The acquisition of OMG's software business
will be another step toward achieving this goal."

Under the terms of the agreement, which is expected to close in late August and
is conditional upon a majority vote of OMG shareholders, Pharmacopeia will
acquire OMG's software business for approximately $27 million comprised of cash
and the assumption of certain liabilities. The acquisition will be accounted for
using the purchase method of accounting. Upon completion of the acquisition,
Pharmacopeia will integrate OMG's bioinformatics and cheminformatics products
into its existing Life Sciences software business.

Pharmacopeia (www.pharmacopeia.com) is a leader in enabling science and
technology that accelerates drug discovery and chemical development.
Pharmacopeia's Drug Discovery Services segment integrates proprietary small
molecule combinatorial chemistry, high-throughput screening and informatics to
accelerate its customers' drug discovery efforts. Pharmacopeia's Software
segment, which includes MSI and Synopsys Scientific Systems develops and
commercializes molecular modeling, simulation and informatics software and
services. The drug discovery services and software technologies are integrated
to support: 1) software sales and systems integration services for
pharmaceutical, biotechnology, and chemical research, and 2) lead identification
and optimization for drug discovery. Pharmacopeia employs approximately 550
people, generated 1999 revenues of approximately $104 million, and is
headquartered in Princeton, NJ. Regional operations are in San Diego, CA;
Burlington, MA; Cambridge, England; Leeds, England; Paris, France; Munich,
Germany and Tokyo, Japan.

Oxford Molecular Group is a leading worldwide supplier of integrated discovery
software and collaborative development services, for use by companies and
academic institutions in the fields of pharmaceutical and biotechnology
research.

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WHEN USED ANYWHERE IN THIS DOCUMENT, THE WORDS "EXPECTS", "BELIEVES",
"ANTICIPATES", "ESTIMATES" AND SIMILAR EXPRESSIONS ARE INTENDED TO IDENTIFY
FORWARD-LOOKING STATEMENTS. PHARMACOPEIA HAS BASED THESE FORWARD-LOOKING
STATEMENTS ON ITS CURRENT EXPECTATIONS ABOUT FUTURE EVENTS. SUCH STATEMENTS ARE
SUBJECT TO


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Pharmacopeia to Acquire Software Business From OMG
August 9, 2000
Page 3


RISKS AND UNCERTAINTIES INCLUDING, BUT NOT LIMITED TO, THE SUCCESSFUL
IMPLEMENTATION OF PHARMACOPEIA'S NEW STRATEGIC PLAN, THE ACCEPTANCE OF NEW
PRODUCTS, THE OBSOLESCENCE OF EXISTING PRODUCTS, THE RESOLUTION OF EXISTING AND
POTENTIAL FUTURE PATENT ISSUES, ADDITIONAL COMPETITION, CHANGES IN ECONOMIC
CONDITIONS, AND OTHER RISKS DESCRIBED IN DOCUMENTS PHARMACOPEIA HAS FILED WITH
THE SECURITIES AND EXCHANGE COMMISSION, INCLUDING ITS MOST RECENT REPORT ON FORM
10-K AND SUBSEQUENT REPORTS ON FORM 10-Q. ALL FORWARD-LOOKING STATEMENTS IN THIS
DOCUMENT ARE QUALIFIED ENTIRELY BY THE CAUTIONARY STATEMENTS INCLUDED IN THIS
DOCUMENT AND SUCH FILINGS. THESE RISKS AND UNCERTAINTIES COULD CAUSE ACTUAL
RESULTS TO DIFFER MATERIALLY FROM RESULTS EXPRESSED OR IMPLIED BY
FORWARD-LOOKING STATEMENTS CONTAINED IN THIS DOCUMENT. THESE FORWARD-LOOKING
STATEMENTS SPEAK ONLY AS OF THE DATE OF THIS DOCUMENT. PHARMACOPEIA DISCLAIMS
ANY UNDERTAKING TO PUBLICLY UPDATE OR REVISE ANY FORWARD-LOOKING STATEMENTS
CONTAINED HEREIN TO REFLECT ANY CHANGE IN ITS EXPECTATIONS WITH REGARD THERETO
OR ANY CHANGE IN EVENTS, CONDITIONS OR CIRCUMSTANCES ON WHICH ANY SUCH STATEMENT
IS BASED.