<PAGE>   1
                                                                  EXHIBIT 10.47


                    CONSULTING AND INTERIM SERVICES AGREEMENT


         This CONSULTING AND INTERIM SERVICES AGREEMENT (this "Agreement"), is
dated this 28th day of June, 1996, by and between ChemGenics Pharmaceuticals
Inc., a Delaware corporation ("ChemGenics"), and PerSeptive Biosystems, Inc., a
Delaware corporation ("PBIO").

                                   WITNESSETH

         WHEREAS, ChemGenics and PBIO have entered into a Master Agreement dated
as of May 7, 1996 (the "Master Agreement"), pursuant to which ChemGenics has
acquired from PBIO and its affiliates assets, projects and activities relating
to drug discovery activities and efforts (the "Drug Discovery Program");

         WHEREAS, in connection with the execution of the Master Agreement, PBIO
has provided certain consulting services through its employees who have worked
in the Drug Discovery Program and ChemGenics has agreed to compensate PBIO for
such services;

         WHEREAS, in connection with the pursuit of drug discovery, ChemGenics
has requested and PBIO is willing to provide on the terms set forth herein,
certain equipment, supplies and other assets following the closing of the
transactions contemplated by the Master Agreement; and

         WHEREAS, PBIO has agreed to provide certain consulting services to
ChemGenics as set forth in this Agreement.

         NOW THEREFORE, in consideration of the foregoing and the mutual
promises set forth herein and in the Master Agreement, and for other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties agree as follows:

         1. Interim Period Compensation. Upon execution of this Agreement,
ChemGenics shall pay PBIO the sum of One Hundred Thirteen Thousand Seven Hundred
Ninety Dollars ($113,790) which amount is equal to the amount paid by PBIO for
salary and benefits for the individuals listed on Exhibit A hereto (the "Drug
Discovery Program Employees") from and including May 8, 1996 through the date
hereof. PBIO shall invoice ChemGenics separately for, and ChemGenics shall
promptly reimburse PBIO for, expenses reimbursed to the Drug Discovery Program
Employees for out-of-pocket expenses incurred during such period in accordance
with PBIO's normal business practices.
<PAGE>   2
         2. PBIO Services to be Provided. During the five year period commencing
on the date hereof PBIO shall provide reasonable strategic technical
consultation to ChemGenics as ChemGenics may reasonably request from time to
time, such consultation to include principally the services of Noubar Afeyan and
Fred Regnier, or such other person(s) as may be PBIO's Chief Executive Officer
("CEO") and Chief Technical Officer, respectively during such period, and other
senior PBIO technical staff members as PBIO may deem appropriate. The scope of
such consultation shall be providing strategic technical advice relevant to the
implementation and utilization of (i) technology licensed to ChemGenics pursuant
to the License Agreement (as defined in the Master Agreement), (ii) prototype
systems, instruments and other equipment to which ChemGenics has access pursuant
to the License Agreement and (iii) equipment provided to ChemGenics pursuant to
this Agreement. It is understood and agreed that such consultation (a) shall be
provided at times and under circumstances reasonably convenient to the provider,
giving due regard to the provider's other priorities, and (b) shall not require
Dr. Afeyan, Dr. Regnier or any other person to interfere with or compromise
their primary responsibilities as officers or employees of PBIO.

         In addition, during such five year period, PBIO shall make (a) Noubar
Afeyan (or such other person as may be PBIO's CEO) available to serve as the
Chairman of the Board of and a member of the Scientific Advisory Board of
ChemGenics, and (b) Fred Regnier or another Senior PBIO employee reasonably
acceptable to ChemGenics available to serve as a member of ChemGenics Scientific
Advisory Board if ChemGenics so requests.

         3. Supplies To Be Provided BY PBIO. During the three year period
commencing on the date hereof, from time to time at ChemGenics' reasonable
request made in advance in accordance with PBIO's customary ordering
requirements and practices, or in accordance with such other procedure as may be
agreed upon by the parties, PBIO shall provide ChemGenics with supplies in
quantities and with specifications reasonably designated by ChemGenics and which
are either manufactured by PBIO or of which PBIO is a distributor ("Supplies"),
provided that PBIO shall not be obligated to provide more than $500,000 of such
Supplies valued at fully burdened manufactured cost for Supplies manufactured by
PBIO and the actual cost of acquisition for Supplies distributed by PBIO.
ChemGenics agrees that it will provide PBIO with as much advance notice of its
requirements for such Supplies as is reasonably practicable. PBIO agrees that it
will utilize its reasonable best efforts to meet ChemGenics requirements for
Supplies and delivery times, and to provide ChemGenics with written notice of
its inability to meet such delivery dates and the date on which delivery is
projected to be actually made. PBIO further agrees that it will treat ChemGenics
with respect to such Supplies on a

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reasonable parity with PBIO's other customers, provided that ChemGenics gives
PBIO commercially reasonable advance notice to permit PBIO to accommodate its
customer's requirements and ChemGenics' requests. PBIO will provide ChemGenics
with written reports not less than semi-annually if requested by ChemGenics
detailing the Supplies provided and the cost thereof. The term "fully burdened
manufactured cost" shall mean the direct manufactured cost of an item as shown
on PBIO's books and records plus a fair allocation of all absorbed and
unabsorbed overhead manufacturing costs whether included or excluded from the
overhead pool for inventory valuation purposes, in each case as certified in
writing on an annual basis by PBIO's Chief Financial Officer to fairly represent
the fully burdened manufacturing costs. ChemGenics shall have the right on an
annual basis to inspect, review and/or audit PBIO's books and records, including
work papers, utilized to determine fully burdened manufactured costs. In the
event any such inspection, review or audit results in a determination that PBIO
has overcharged ChemGenics by more than 10%, PBIO shall reimburse ChemGenics'
costs of such inspection, review or audit.

         4. Equipment To Be Provided By PBIO. A. During the three year period
commencing on the date hereof, PBIO shall loan to ChemGenics reasonable amounts
and kinds of equipment and instruments ("Equipment") manufactured by PBIO or of
which PBIO is a distributor and which are reasonably available to PBIO and
reasonably necessary for ChemGenics to pursue effectively the Drug Discovery
Program as outlined in its initial business plan (the "Business Plan") approved
by ChemGenics' Board of Directors or in a prospectus contained in a registration
statement filed by ChemGenics with the Securities and Exchange Commission with
respect to ChemGenics' initial public offering of securities. ChemGenics agrees
that it will provide PBIO with as much advance notice of its requirements for
such Equipment as is reasonably practicable. PBIO agrees that it will utilize
its reasonable best efforts to meet ChemGenics requirements for Equipment and
delivery times, and to provide ChemGenics with written notice of its inability
to meet such delivery dates and the date on which delivery is projected to be
actually be made. PBIO further agrees that it will treat ChemGenics with respect
to such Equipment on a reasonable parity with PBIO's other customers, provided
that ChemGenics gives PBIO commercially reasonable advance notice to permit PBIO
to accommodate its customer's requirements and ChemGenics' requests. Each such
Equipment loan shall be for a period of two years from the date the Equipment is
delivered to ChemGenics, and shall be free of rent or other fees, provided that
notwithstanding the foregoing, no period of loan of any Equipment shall extend
beyond the date which is four years from the date hereof, no matter when the
period of the loan begins. After the termination of the loan period of each
piece of Equipment, the Equipment shall be returned

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to PBIO in the same condition as received (subject only to reasonable wear and
tear and casualty loss) or purchased by ChemGenics at the lesser of depreciated
book value (based on actual cost and depreciation or amortization schedules
utilized by PBIO in the ordinary course of its business) or fair market value
(as agreed by the parties or in the absence of such agreement by an appraiser
selected by the parties, the cost of which shall be shared equally by the
parties). To the extent such Equipment can be purchased or leased or
compensation otherwise received therefor by ChemGenics as a part of a contract
or arrangement with a partner or other party and charged to the contract or
arrangement, then such Equipment shall not be loaned to ChemGenics by PBIO but
shall be purchased by ChemGenics if reasonable under the circumstances and the
terms of its arrangement with the third party. The payment amount shall be the
greater of (i) if ChemGenics sells the Equipment to the customer, the amount
paid by the customer and (ii) the price PBIO in its reasonable discretion would
charge a favored customer therefor. In case of a dispute the price will be the
average price of the lowest 3 of the last 10 sales (or such fewer number as sold
in the prior year) of comparable items of Equipment sold to PBIO's retail
customers, excluding distributors. ChemGenics will use reasonable efforts to
include Equipment purchase requirements or, if not feasible, lease or other
compensation mechanisms in its third party contracts and other arrangements.
ChemGenics will insure such Equipment with replacement cost insurance pursuant
to an insurance policy reasonably satisfactory to PBIO, and shall include PBIO
as an additional insured, will provide customary maintenance and repair, and, if
destroyed shall pay PBIO the replacement cost thereof.

         PBIO shall not be required to loan to ChemGenics any Equipment that is
the same, substantially similar or functionally equivalent to Equipment which
had been the subject of a loan during the six month period prior to the date of
any loan request, unless such Equipment was destroyed by casualty, ChemGenics is
still utilizing such Equipment and can reasonably utilize the additional
Equipment in accordance with the Business Plan or elects to purchase from PBIO
the Equipment which was subject to such prior loan.

         ChemGenics will provide PBIO with written reports not less than
semi-annually if requested by PBIO detailing the location, use and status of
each piece of Equipment loaned to ChemGenics pursuant to this Agreement, and
containing such other information as PBIO may reasonably request.

         In the event that ChemGenics receives from third parties rental, fees
or other direct payments for the rental or use of Equipment, ChemGenics shall
remit to PBIO 90% of the amount received by ChemGenics which is directly related
to the use of the Equipment (including rent) within 30 days from the date of
receipt

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<PAGE>   5
by ChemGenics (but without duplication of amounts referred to above), and such
amount shall be credited toward any amount payable for the purchase of such
Equipment, if ChemGenics elects to purchase rather than return same. In the
event ChemGenics elects to return rather than purchase any such Equipment, PBIO
shall retain any amounts paid or payable to it by ChemGenics with respect to
such Equipment.

         Without PBIO's express written consent, no Equipment loaned to
ChemGenics pursuant to this Agreement shall be furnished to any Partner or any
other third party, or otherwise removed from ChemGenics' facility, unless it has
been purchased or leased from ChemGenics for fair consideration as described
above, provided that nothing contained herein shall prevent ChemGenics from
utilizing such Equipment in the ordinary course of its business with any
Partner.

         ChemGenics shall be responsible, and PBIO shall have no obligation, for
the maintenance and repair of Equipment loaned or otherwise provided to
ChemGenics pursuant to this Agreement, except for such maintenance and repair as
PBIO agrees in writing to provide. PBIO shall afford ChemGenics the opportunity
to enter into service and maintenance agreements relating to Equipment on terms
and conditions which PBIO makes available to its customers generally.

         B. So long as ChemGenics occupies space on the third floor of the
Framingham Facility pursuant to the Sublease, PBIO and ChemGenics agree to
permit the other to use certain instruments as set forth on the last page of the
Inventory List which constitutes a part of Schedule 1.01(b) of the Master
Agreement.

         C. During such period as ChemGenics occupies at least 500 square feet
of space used principally for laboratory purposes at PBIO's facility at 500 Old
Connecticut Path, Framingham, Massachusetts, or any replacement facility in
which a substantial part of PBIO's business is also located, in the event that
ChemGenics or PBIO would benefit from and requests the use of an instrument or
item of equipment which is owned or otherwise controlled by the other and as to
which a like instrument is not otherwise available to the requesting party for
the use intended, and such use would not violate any law, rule or regulation, or
any agreement to which either ChemGenics or PBIO is bound, or, in the opinion of
the party owning or controlling the use thereof, disclose any trade secret or
other confidential information which such party does not wish disclosed, and
such instrument or item of equipment is not required at the time requested for
any reason in the sole discretion of the party owning or otherwise controlling
the use of such instrument or equipment and can be made available for use on
terms and conditions acceptable to the party owning or

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<PAGE>   6
controlling the use of same in its sole discretion, the other party may use such
instrument or item of equipment upon reasonable advance notice and at such times
and on such terms and conditions as the party owning or controlling the use of
such instrument or equipment may impose, but without the payment of a rental or
other fee, and without liability of any kind or nature by the lending party for
any damage of any kind or nature arising out of the use thereof. It is expressly
understood and agreed that the party owning or otherwise controlling the use of
any such instrument or equipment shall retain absolute priority as to its use
and shall have sole discretion as to the terms and conditions of use. It is
further expressly understood and agreed that the provisions set forth in this
paragraph are in addition to and in no way modify PBIO's obligation to provide
ChemGenics' use of equipment as set forth in Schedule 1.01(b) of the Master
Agreement and Section 4.1.6 of the License Agreement.

         D. All consulting, supplies, instruments and other services and goods
provided or supplied to ChemGenics pursuant to this Agreement shall be provided
subject to all limitations and conditions pursuant to which such services or
goods are provided to customers of PBIO. ChemGenics shall use any such services,
supplies, instruments or other products solely at its own risk and without
recourse to PBIO or the provider thereof, except (i) as to Claims of
intellectual property infringement in connection with the use by ChemGenics of
Equipment or Supplies, as otherwise set forth in Exhibit B hereto, subject to
the limitations set forth therein, and (ii) as to Claims arising from PBIO's
negligence, as to which PBIO shall be liable to the extent of its negligence. In
any event, and notwithstanding anything contained in this Agreement or any other
agreement to the contrary, PBIO's sole obligation, and ChemGenics' sole and
exclusive remedy, with respect to any consulting or other services or supplies,
instruments or other goods which do not meet any actual or implied warranty,
representation or standard, or any warranty, representation or standard which
may be agreed to by PBIO or which may be imposed by any statute or law, or as to
which PBIO breached or is claimed to have breached any agreement, covenant or
commitment of any kind, will be to perform such service or repair or replace, at
its discretion, such supplied product, instrument or other good.

NOTWITHSTANDING THE FORGOING, OR ANYTHING CONTAINED HEREIN TO THE CONTRARY, IN
NO EVENT SHALL PBIO BE LIABLE, WHETHER IN CONTRACT, IN TORT, WARRANTY, OR UNDER
ANY STATUTE (INCLUDING WITHOUT LIMITATION ANY TRADE PRACTICE, UNFAIR COMPETITION
OR OTHER STATUTE OF SIMILAR IMPORT) OR ON ANY OTHER BASIS, FOR INDIRECT,
PUNITIVE, MULTIPLE, INCIDENTAL, STATUTORY CONSEQUENTIAL OR SPECIAL DAMAGES
SUSTAINED BY CHEMGENICS OR ANY OTHER PERSON, NO MATTER HOW ARISING WHETHER OR
NOT FORESEEABLE AND WHETHER OR NOT PERSEPTIVE IS ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE, INCLUDING, WITHOUT LIMITATION, DAMAGES

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ARISING FROM OR RELATED TO LOSS OF USE, LOSS OF DATA, FAILURE OR INTERRUPTION IN
THE OPERATION OF ANY EQUIPMENT OR SOFTWARE, DELAY IN REPAIR OR REPLACEMENT, OR
FOR LOSS OF REVENUE OR PROFITS, LOSS OF GOODWILL OR LOSS OF BUSINESS.

         Indemnification. To the fullest extent permitted by law, ChemGenics
agrees to indemnify and hold PerSeptive harmless from and against any and all
claims, demands, obligations, costs, expenses (including reasonable attorney's
fees and expenses) and liabilities (collectively, "Claims") including, without
limitation, those arising from violations of local, state, or federal food and
drug, environmental, health and safety and other laws, codes and regulations,
arising from or relating to ChemGenics use of Equipment, Supplies and other
products hereunder, except to the extent of Claims resulting from the breach by
PBIO of its obligations hereunder or PBIO's negligence, as to which PBIO shall
indemnify and hold ChemGenics harmless from any such Claims.

         5. Certain Consequences of Noncompliance. In the event PBIO does not
provide the Equipment and Supplies required by Sections 3 and 4 of this
Agreement, or the Consulting Services required by Section 2 of this Agreement,
ChemGenics shall provide written notice of such failure to PBIO. If PBIO fails
to cure such failure within thirty (30) days following receipt of the first such
notice, twenty (20) days following receipt of the second such notice or ten (10)
days following receipt of any further notice, or if such failure is not curable
in such period PBIO fails to commence to cure same within such period and
thereafter diligently continue to prosecute such cure and in any event fails to
cure such failure within an additional twenty (20) days, ChemGenics shall have
the option for a period of ninety (90) days following the termination of the
grace period following such notice to purchase from PBIO and PBIO shall be
obligated to sell to ChemGenics at an aggregate price of $1.00, all or any part
of the number of the Earnout Shares (the "Shares") set forth below (the
"Repurchase Option").
<TABLE>
<CAPTION>
         Date of Default*                  Number of Shares
         ----------------                  ----------------

<S>                                                     <C>
July 1, 1996 - June 30, 1997                            979,268
July 1, 1997 - June 30, 1998                            652,844
July 1, 1998 - June 30, 1999                            326,422
         Thereafter                                           0
</TABLE>

*The applicable number of shares shall be determined by the period in which the
date of default, set forth in the relevant default notice, occurs.

         In the event ChemGenics shall be entitled to and shall elect to
exercise the Repurchase Option, it shall give PBIO written notice specifying the
number of Shares which ChemGenics elects to

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<PAGE>   8
purchase and specifying a date for closing hereunder, which date shall be not
more than thirty (30) calendar days after the giving of such notice. The closing
shall take place at ChemGenics' principal offices or such other location in the
greater Boston, Massachusetts area as ChemGenics may reasonably designate in
such notice. At the closing, PBIO shall deliver the Shares being purchased
against the simultaneous delivery of the purchase price by ChemGenics.

         If PBIO notifies ChemGenics that it disagrees with ChemGenics assertion
that there is a default, and notifies ChemGenics of the same within fifteen (15)
calendar days after PBIO's receipt of notice thereof, the matter will be
referred to and determined by arbitration pursuant to Section 10.8 of the Master
Agreement.

         In the event that PBIO fails to deliver the Shares as required by this
Agreement, ChemGenics may elect (a) to establish a segregated account to receive
the payment of $1.00, such account to be turned over to PBIO upon delivery of
the certificates representing such Shares, and (b) immediately to take such
action as is appropriate to transfer record title of such Shares from PBIO to
ChemGenics and to treat PBIO and such Shares in all respects as if delivery of
the certificates representing such Shares had been made as required by this
Agreement. PBIO hereby irrevocably grants ChemGenics a power of attorney for the
purpose of effectuating the foregoing.

         If ChemGenics shall pay a stock dividend or declare a stock split on or
with respect to any of its Common Stock, or otherwise distribute securities of
ChemGenics to the holders of its Common Stock, the number of shares of stock or
other securities of ChemGenics issued with respect to the Shares then subject to
the Repurchase Option shall be added to the Shares then subject to the
Repurchase Option without any change in the aggregate purchase price. If
ChemGenics shall distribute to its stockholders shares of stock of another
corporation, the shares of stock of such other corporation distributed with
respect to the Shares then subject to the Repurchase Option shall be added to
the Shares covered by the Repurchase Option without any change in the aggregate
purchase price.

         If the outstanding shares of ChemGenics' Common Stock shall be
subdivided into a greater number of shares or combined into a smaller number of
shares, or in the event of a reclassification of the outstanding shares of
Common Stock of ChemGenics, or if ChemGenics shall be a party to any capital
reorganization, there shall be substituted for the Shares then covered by the
Repurchase Option such amount and kind of securities as are issued in such
subdivision, combination, reclassification, or capital reorganization in respect
of the Shares subject to the Repurchase

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<PAGE>   9
Option immediately prior thereto, without any change in the aggregate purchase
price.

         6. ChemGenics and PBIO also agree to the terms and conditions set forth
on Exhibit A to this Agreement, relating to services to be provided by PBIO to
ChemGenics during such time as ChemGenics occupies space on the third floor of
Building A of PerSeptive's Framingham Facility.

         7. Confidentiality. In connection with the Services to be provided
hereunder, each party may have access to certain confidential information of the
other. Such confidential information shall be maintained in confidence and
access to and use of shall be restricted in accordance with the terms of the
Non-Competition and Confidentiality Agreement of even date herewith.

         8. Termination. This Agreement shall continue until June 30, 2001,
provided, however, that this Agreement shall terminate immediately upon a
rescission of the Master Agreement pursuant to Section 8.07 thereof. In the
event of any such termination, ChemGenics shall promptly return to PBIO all
Equipment in as good a condition as received, reasonable wear and tear excepted
(other than any Equipment purchased by ChemGenics in accordance with Section 4)
and unused Supplies.

         9. Certain Termination Costs. On the date hereof, ChemGenics shall
offer employment to each of the Drug Discovery Program Employees at a salary no
less than their current salary with PBIO. In the event ChemGenics terminates the
employment of any of the Drug Discovery Program Employees, ChemGenics will
provide severance pay to such individuals, calculated in accordance with
ChemGenics customary severance policies, such calculation (i) not to exceed two
weeks per year of service, (ii) to include the service of such individual with
PBIO as set forth in PBIO's books [for severance certification purposes only],
and (iii) to be not less than three weeks or more than ten weeks for any
individual ("Severance Pay"). PBIO will on demand pay or reimburse ChemGenics
for the payment of all Severance Pay and other severance related costs for the
Drug Discovery Program Employees in excess of the Space Value. PBIO shall remain
responsible for and indemnify ChemGenics against all claims of any Drug
Discovery Program Employee to the extent arising out of any act or omission of
PBIO or violation of any law, rule or regulation by PBIO prior to their being
employees of ChemGenics. Except as set forth above, ChemGenics shall be
responsible for and shall indemnify PBIO against claims of any Drug Discovery
Program Employee to the extent arising out of any act or omission or violation
of any law, rule or regulation by ChemGenics on or after the date such employee
became an employee of ChemGenics. PBIO will also on demand pay or reimburse
ChemGenics for the payment of all Severance Pay and other

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<PAGE>   10
out of pocket severance related costs for one Drug Discovery Program Employee
identified by ChemGenics.

         Space Value shall mean 45% of the value of the portion of the premises
on the third floor of Building A of PBIO's Framingham facility to be first
occupied by ChemGenics pursuant to the Sublease (the "ChemGenics Space"), during
the period between the date hereof and the date of termination of this Agreement
in accordance with the proviso in Section 8 above, it being understood and
agreed that 45% percent of the ChemGenics Space represents the portion of
ChemGenics Space that was not used by the Drug Discovery Program prior to the
date of execution of the Master Agreement. The value of the ChemGenics Space
shall be $12.50 (Twelve Dollars and Fifty Cents) per square foot per year, or
$0.03427 per square foot per day. The ChemGenics Space occupies 6,278 square
feet. Accordingly, the Space Value shall be calculated by multiplying $0.03427
times 0.45 times 6,278 square feet times the number of days from and including
May 7, 1996 to and including the date the transactions contemplated by the
Master Agreement are rescinded and unwound, or such later date as ChemGenics'
occupancy of the ChemGenics Space without the payment of Fixed Rent (as defined
in the Sublease) terminates (the later of such dates being herein called the
"ChemGenics Space Termination Date"). For example, if the duration of the period
between May 7, 1996 and ChemGenics Space Termination Date was six months, the
Space Value would be $17,415.

         10.      Miscellaneous.

         (a) Entire Agreement. This Agreement, including the Exhibit attached
hereto, sets forth the entire agreement and understanding of the parties hereto
and supersedes all prior oral or written agreements and understandings relating
to the subject matter hereof.

         (b) Assignment. Except as set forth in paragraph 10(c) no right,
benefit or interest hereunder shall be subject to assignment, transfer,
anticipation, alienation, sale, encumbrance, charge, pledge, hypothecation or
set-off in respect of any claim, debt or obligation or to execution, attachment,
levy or similar process.

         (c) Successors and Assigns. The terms and provisions of this Agreement
shall inure to the benefit of, and be binding upon, PBIO, ChemGenics, and their
respective successors and assigns; provided, however, that ChemGenics and PBIO
may not assign or otherwise transfer this Agreement or any rights and interests,
nor delegate any obligations, hereunder, except to a direct or indirect 100%
parent or direct or indirect wholly-owned subsidiary which becomes a party to
the Non-Competition Agreement (as defined in the Master Agreement) and that
agrees in writing to be bound by this Agreement

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<PAGE>   11
(and in such case ChemGenics and PBIO shall remain bound) without the prior
written consent of the other party to this Agreement, except pursuant to a
merger or consolidation, or sale of all or substantially all of the stock,
assets or business of PBIO or ChemGenics and their respective subsidiaries taken
as a whole as provided below, if the new owner or successor becomes a party to
the Noncompetition Agreement, and except that without PBIO's consent ChemGenics
rights under this Agreement may not be so assigned or otherwise transferred in a
transaction that would give PBIO the right to terminate the License Agreement
pursuant to Section 9.4 thereof. In the event that either PBIO or ChemGenics
shall (i) consolidate or merge with another entity (other than an acquisition by
such party of another entity where the stockholders of PBIO or ChemGenics (or
any subsidiary of PBIO or ChemGenics), after such transaction directly or
indirectly own at least a majority of the voting stock of the combined or
acquired entity); or (ii) convey, sell or lease to another entity all or
substantially all of its stock, assets or business and its subsidiaries, taken
as a whole; or (iii) if there shall be a change of control of either PBIO or
ChemGenics, then (A) if such transaction is negotiated by PBIO or ChemGenics,
such party shall give the other party written notice identifying the acquiring
entity and the material terms of the transaction at least thirty (30) days prior
to the closing thereof and (B) the parties shall negotiate in good faith to
determine whether any changes shall be appropriate in this Agreement. Any
attempt to assign or delegate any portion of this Agreement in violation of this
Section 9(c) shall be null and void. Subject to the foregoing, any reference to
PBIO and ChemGenics hereunder shall be deemed to include the permitted
successors thereto and assigns thereof.

         (d) Amendment. This Agreement may not be amended, modified or canceled
except by written agreement of the parties hereto.

         (e) Severability. In the event that any court of competent jurisdiction
shall determine that any provision contained in this Agreement shall be
unenforceable in any respect, then such provision shall be deemed limited to the
extent that such court deems it enforceable, and as so limited shall remain in
full force and effect. In the event that such court shall deem any provision
wholly unenforceable, the remaining provisions of this Agreement shall
nevertheless remain in full force and effect.

         (f) Applicable Law. This Agreement has been made in and shall be
governed by and construed in accordance with the laws of the Commonwealth of
Massachusetts, without giving effect to the conflict of law principles thereof.


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<PAGE>   12
         (g) Survival. The provisions contained in Section 8 of this Agreement
shall survive the expiration or earlier termination of this Agreement.

         (h) Waivers and Consents. The terms and provisions of this Agreement
may be waived, or consent for the departure therefrom granted, only by a written
document executed by the party entitled to the benefits of such terms or
provisions. Each such waiver or consent shall be effective only in the specific
instance and for the purpose for which it was given, and shall not constitute a
continuing waiver or consent.

         (i) Notices. All notices, requests, consents and other communications
hereunder shall be in writing, shall be addressed to the receiving party's
address set forth below or to such other address as a party may designate by
notice hereunder, and shall be either (i) delivered by hand, (ii) made by telex,
telecopy or facsimile transmission, (iii) sent by overnight courier, or (iv)
sent by certified mail, return receipt requested, postage prepaid:

         If to ChemGenics:                  ChemGenics Pharmaceuticals Inc.
                                            One Kendall Square
                                            Building 300
                                            Cambridge, MA 02139
                                            Attn: President

         If to PBIO:                        PerSeptive Biosystems, Inc.
                                            500 Old Connecticut Path
                                            Framingham, MA 01701
                                            Attn: President
                                            CC:  General Counsel

         All notices, requests, consents and other communications hereunder
shall be deemed to have been given either (i) if by hand, at the time of the
delivery thereof to the receiving party at the address of such party set forth
above, (ii) if made by telex, telecopy or facsimile transmission, at the time
that receipt thereof has been acknowledged by electronic confirmation or
otherwise, (iii) if sent by overnight courier, on the next business day
following the day such mailing is made, or (iv) if sent by certified mail, on
the 5th business day following the day such mailing is made.

         (j) Counterparts. This Agreement may be executed in one or more
counterparts each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.


                                     - 12 -
<PAGE>   13
         IN WITNESS WHEREOF, the undersigned parties have duly executed and
delivered this Agreement under seal as of the day and year first above written.

                                             CHEMGENICS PHARMACEUTICALS INC.



                                             By: /s/ Barry A. Berkowitz
                                                 -------------------------------
                                                  Barry A. Berkowitz, President



                                             PERSEPTIVE BIOSYSTEMS, INC.



                                             By: /s/ Noubar B. Afeyan
                                                 -------------------------------
                                                  Noubar B. Afeyan, President

Consulting and Interim
Services Agreement

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