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                                  CHIREX INC.


             SPECIAL SCIENTIIC ADVISORY BOARD CONSULTING AGREEMENT
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     THIS SPECIAL SCIENTIFIC ADVISORY BOARD CONSULTING AGREEMENT (the
"Agreement"), made as of this 19th  day of July, 1996, is entered into by CHIREX
INC., a Delaware corporation with its principal offices at 65 William Street,
Wellesley, MA 02181 (the "Company") and Eric N. Jacobsen, Ph.D., with an address
at Harvard University, Cambridge, Massachusetts (the "Consultant").

                                 INTRODUCTION
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     The Company desires to retain the services of the Consultant as a
consultant to the Company and as a member of its Scientific Advisory Board
("SAB") and the Consultant desires to serve as a consultant to the Company and
as a member of its SAB.  Accordingly, the parties agree as follows:

     1.  Services

         1.1   General. The Consultant agrees to serve on the SAB and to use
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his best efforts to perform such consulting, advisory and related services for
the Company as may be reasonably requested from time to time by the Company. The
Company anticipates that the SAB shall meet two times each year, at times and
locations to be determined by the Company in consultation with SAB members. If
the Consultant has a conflict of interest, or potential conflict of interest,
with respect to any matter presented at a meeting of the SAB, he shall excuse
himself from the discussion of such matter. The delivery by the Consultant of
consulting, advisory and related services hereunder not involving attendance at
meetings of the SAB shall be at such times and at such locations as the
Consultant and the Company may agree from time to time. The Company agrees that
such consulting services shall not require a commitment of the Consultant's time
in excess of an aggregate of four and one-half days per month. In addition, the
Consultant shall not be required to devote more than an aggregate of four days
per year to the attendance at and participation in meetings of the SAB.

         1.2   Fields.    During the Consultation Period (as defined below), the
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Consultant shall consult with the Company in the field of pharmaceutical fine
chemicals with special reference to asymmetric synthesis of organic compounds.
The Consultant shall also consult with and advise the Company with respect to
such other matters as the Company may reasonably request from time to time or as
may be presented at meetings of the SAB.

     2.  Term. This Agreement shall be effective as of July 1, 1996 and shall
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continue until July 1, 2001, unless extended by mutual written consent or sooner
terminated as provided below (the "Consultation Period").  Either party to this
Agreement may terminate the Consultation Period upon 60 days' prior written
notice to the other party, provided, however, that 
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the terms of Sections 4.1 and 7 shall not terminate but shall remain in full
force and effect. In the event of such termination, the Consultant shall be
entitled to payment for services performed and expenses paid or incurred prior
to the effective date of termination.

     3. Compensation. The Company shall pay the Consultant a monthly retainer of
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$1,666.67 for an aggregate of two and one half days per month of compensable
services for the Company. For any services provided by the Consultant in excess
of two and one half days in any month, the Company shall pay the Consultant at
the rate of $666.67 per day (i.e., per eight hours of effort), payable monthly
upon receipt of a statement of services rendered. Without prior mutual
agreement, the Company will not request, and the Consultant will not spend, more
than an aggregate of two and one half days per month on compensable services for
the Company. The Company shall reimburse the Consultant for all reasonable and
necessary expenses incurred or paid by the Consultant in connection with, or
related to, attendance at SAB meetings (which shall not require prior approval
of the Company) or the performance of consulting services hereunder (which shall
require prior approval of the Company) or the performance of consulting services
hereunder (which shall require prior approval of the Company) within 30 days of
receipt of an itemization and documentation of such expenses.

     4.  Proprietary Information; Inventions; Non-Competition
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         4.1  Proprietary Information.  The Consultant acknowledges that his
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relationship with the Company is one of high trust and confidence and that in
the course of his service to the Company he will have access to and contact with
Proprietary Information or Invention (as defined in Section 4.2 below).  For
purposes of this Agreement, Proprietary Information shall mean all information
(whether or not patentable and whether or not copyrightable) owned, possessed or
used by the Company or any third party, including, without limitation, any
Invention, formula, trade secret, process, research, report, technical data,
know-how, technology and marketing or business plan, that is communicated to,
learned or, developed or otherwise acquired by the Consultant in the course of
his performing consulting services to the Company hereunder.  The Consultant's
obligations under this Section 4.1 shall not apply to any information that (i)
is or becomes known to the general public under circumstances involving no beach
by the Consultant or others of the terms of this Section 4.1, (ii) is generally
disclosed to third parties by the Company without restriction on such third
parties or (iii) is in the Consultant's possession at the time of disclosure
otherwise than as a result of a prior disclosure by the Company to the
Consultant or a to a third party under an obligation of confidentiality with
respect thereto.  The Consultant represents that his retention as a Consultant
with the Company and his performance under this Agreement, does not, and shall
not, breach any agreement that obligates him to keep in confidence any trade
secrets or confidential or proprietary information of his or of any other party
or to refrain from competing, directly or indirectly, with the business of any
other party.  The Consultant shall not disclose to the Company any trade secrets
or confidential or proprietary information of any party.

         4.2   Inventions. All inventions, discoveries, technology, designs,
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innovations and improvements related to the business of the Company which are
made, conceived or reduced to practice by the Consultant, solely or jointly with
others, during the consultation Period which arise directly from information and
discussions presented to the SAB members at their meetings 
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or which are provided to the Company during the SAB meetings or on other
occasions or while providing consulting services to the Company or during a
meeting of the SAB (collectively, the "Inventions") shall be the sole property
of the Company. The Consultant hereby assigns to the Company all Inventions and
any and all related patents, copyright, trademarks, trade names, and other
industrial and intellectual property rights and applications therefor, in the
United States and elsewhere and appoints any officer of the Company as his duly
authorized attorney to execute such further assignments, documents and other
instruments as may be necessary or desirable to fully and completely assign all
Inventions to the Company and to assist the Company in applying for, obtaining
and enforcing patens or copyrights or other rights in the United States and in
any foreign country with respect to any Invention.

         4.3 Non-Competition The Consultant agrees that, during the consultation
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Period, he will not, directly or indirectly, without the prior written consent
of the Company, whether alone or in association with others, in the United
States of America or in any foreign nation, state or jurisdiction, become
associated with, render advisory, consulting or other services to, or become
employed by, any person or business enterprise engaging in the commercial
business contemplated or being conducted by the Company.  A business will be
considered "contemplated" only if the Company has written business plans for
entering that business.  The Consultant ha acknowledged to the Company that the
foregoing territorial non-competition restriction for the indicated duration is
appropriate in light of the nature of the businesses to be conducted by the
Company and the Consultant's unique position within this specialized field.

     5. Independent Contractor Status. The Consultant shall perform all services
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under this Agreement as an "independent contractor" and not as an employee or
agent of the Company.  The Consultant is not authorized to assume or create any
obligation or responsibility, express or implied, on behalf of, or in the name
of, the Company or to bind the Company in any manner.

     6. Consent to Use of Name. The Consultant hereby consents to the use of his
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name by the Company, as required, in connection with any previous, current or
future offering and ongoing registration of securities of the Company including,
but not limited to, an registration statement, prospectus or other document
filed with the Securities and Exchange Commission, any state securities
commission, the National Association of Securities Dealers, Inc. and The Nasdaq
Stock Market.

     7. Miscellaneous. This Agreement constitutes the entire agreement between
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the parties and supersedes all prior agreements and understandings, whether
written or oral, relating to the subject matter of this Agreement. This
Agreement may be amended or modified only by a written instrument executed by
both the Company and the Consultant. This Agreement shall be construed,
interpreted and enforced in accordance with the laws of the Commonwealth of
Massachusetts. The Consultant agrees that a breach of any of the restrictions
set forth in this Agreement would cause the Company irreparable injury and
damage, and that, in the event of any breach or threatened breach, the Company,
in addition to all other rights and remedies at law or in equity, shall have the
right to enforce the specific performance of such restrictions and to apply for
injunctive relief against their violation. The invalidity or unenforceability of
any provision hereof (or portion thereof) shall not affect the validity or
enforceability of any other provision hereof, and if any such provision (or
portion thereof) is so broad as to be 
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unenforceable, it shall be interpreted to be only as broad as is enforceable.
This Agreement shall be binding upon, and inure to the benefit of both parties
and their respective successors and assigns, including any corporation with
which, or into which, the Company may be merged or which may succeed to its
assets or business, provided, however that the obligations of the Consultant are
personal and shall not be assigned by him.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date set forth above.



     CHIREX INC.                                CONSULTANT



     By:-------------------------               By:----------------------------
             Alan R. Clark                           Eric N., Jacobsen, Ph.D.
             Chairman and CEO