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                                                           Exhibit 10.23




                STANDARD OFFER, AGREEMENT AND ESCROW
              INSTRUCTIONS FOR PURCHASE OF REAL ESTATE
                          (Non-Residential)

                                                   December 11, 1996
                                       (Date for Reference Purposes)

1.  BUYER.

    1.1  Supergen, Inc., (the "Buyer") hereby offers to purchase the real
property, hereinafter described, from the owner thereof (the "Seller")
(collectively, the "Parties" or individually, a "Party"), through an escrow
(the "Escrow") to close on as provided in Paragraph "D" of Addendum "A"
attached, (the "Expected Closing Date") to be held by First American Title
Guaranty (the "Escrow Holder"), Escrow No. ______, whose address is 5199
Johnson Drive, Suite 120, Pleasanton, CA 94588, Telecopier No. (510)
463-9683, upon the terms and conditions set forth in this agreement (the
"Agreement").  Buyer shall have the right to assign Buyer's rights hereunder,
but any such assignment shall not relieve Buyer of Buyer's obligations herein
unless the Seller expressly releases Buyer.

    1.2  The term "Date of Agreement" as used herein shall be the date when
by execution and delivery (as defined in Paragraph 20.2) of this document or
a subsequent counter-offer thereto, Buyer and Seller have reached Agreement
in writing whereby Seller agrees to sell, and Buyer agrees to purchase, the
Property upon terms accepted by both Parties.

2.  BROKER.

    2.1  The real estate broker or brokers presenting this Agreement to Seller
are: (Check applicable box(es).)

    Lee & Associates C.R.E.S. - Bob Kumnick, who, with respect to this
Agreement, represents:

      / /   the Buyer exclusively ("Buyer's Broker")
      / /   both Buyer and Seller,

and                                   , who, with respect to this Agreement
represents:

      / /    the Seller exclusively (the "Seller's Broker")
      / /    both the Seller and Buyer,

(the "Broker(s)"), all such named Broker(s) being the procuring cause(s) of
this Agreement.  See Paragraph 26 for Disclosures Regarding the Nature of a
Real Estate Agency Relationship.  Buyer shall use the services of Buyers'
Broker exclusively in connection with any and all negotiations and offers
with respect to the property described in Paragraph 3.1 for a period of one
year from the date above.

    2.2  Buyer and Seller each represent and warrant to the other that
he/she/it has had no dealings with any person, firm, broker or finder in
connection with the negotiation of this Agreement and/or the consummation of
the purchase and sale contemplated herein, other than the Broker(s) named in
Paragraph 2.1, and no broker or other person, firm or entity, other than said
Broker(s) is/are entitled to any commission or finder's fee in connection
with this transaction as the result of any dealings or acts of such Party.
Buyer and Seller do each hereby agree to indemnify, defend, protect and hold
the other harmless from and against any costs, expenses or liability for

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compensation, commission, or charges which may be claimed by any broker,
finder, or other similar party, other than said named Broker(s) by reason of
any dealings or act of the indemnifying Party.

3.  PROPERTY.

    3.1  The real Property (the "Property") that is the subject of this offer
consists of  9,600+ square foot shell building (Refer to Exhibit A,
attached), is located in the City of Pleasanton, County of Alameda, State of
California, and is commonly known by the street address of 1059 Serpentine
Lane, and is legally described as industrial condominium, as described in
Condominium Plan in Exhibits "A" and "B" (Building "B"; Unit "B").

    3.2  If the legal description of the Property is not complete or is
inaccurate, this Agreement shall not be invalid and the legal description
shall be completed or corrected to meet the requirements of First American
Title Guaranty (the "Title Company"), which Title Company shall issue the
title policy hereinafter described.

    3.3  The Property includes, at no additional cost to Buyer, the permanent
improvements thereon, including those items which the law of the state in
which the Property is located provides is part of the Property, as well as
the following items, if any, owned by Seller and presently located in the
Property: electrical distribution systems (power panels, buss ducting,
conduits, disconnects, lighting fixtures), telephone  distribution systems
(lines, jacks and connections), space heaters, air conditioning equipment,
air lines, carpets, window coverings, wall coverings, and none other
(collectively, the "Improvements").

    3.4  If the Property is located in the State of California, the Broker(s)
is/are required under the Alquist-Priolo Special Studies Zones Act, to
disclose to a prospective purchaser of real property whether the property
being purchased is located within a delineated special studies zone (a zone
that encompasses a potentially or recently active trace of an earthquake
fault that is deemed by the State Geologist to be sufficiently active and
well defined enough to constitute a potential hazard to structures from
surface faulting or fault creep).  If the Property is located within such a
special studies zone, its development may require a geologic report from a
state registered geologist.  In accordance with such law, the Broker(s)
hereby inform(s) Buyer that the Property:

         (a)  is not within such a special studies zone.
         (b)  is within such a special studies zone.

4.  PURCHASE PRICE.

    4.1  The purchase price (the "Purchase Price") to be paid by Buyer to
Seller for the Property shall be $744,000.00 payable as follows:

**to be determined between Buyer and bank

              (a) Cash down payment, including the Deposit
              as defined in paragraph 5.3 or if an
              all cash transaction, the Purchase Price):   $114,000.00*
                                                           ------------
(Strike       (b) Amount of "New Loan" as defined in
if not        paragraph 6.1
applicable)   if any:                                      $630,000.00
                                                           ------------




    4.2  If an Existing Deed of Trust permits the beneficiary thereof to
require payment of a transfer fee as a condition to the transfer of the
Property subject to such Existing Deed of Trust, Buyer agrees to pay transfer
fees and costs of up to one and one-half percent (1-1/2%) of the unpaid
principal balance of the applicable Existing Note.

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5.  DEPOSITS.

    5.1  Buyer hereby delivers a check in the sum of $10,000.00, payable to
First American Title, to be (CHECK APPLICABLE BOX) /  / forthwith deposited in
the payee's trust account or /  / held uncashed until the Date of Agreement.
When cashed, the check shall be deposited into the payee's trust account to
be applied toward the Purchase Price of the Property at the Closing, as
defined in Paragraph 7.3  Should Buyer and Seller not enter into an agreement
for purchase and sale, Buyer's check or funds shall, upon request by Buyer,
be promptly returned to Buyer.

    5.2  Within five (5) business days after the Date of Agreement, Buyer
shall deposit with Escrow Holder the additional sum of $0.00*, to be applied
to the Purchase Price at the Closing.  *See Addendum A for additional deposit
information.

    5.3  The funds deposited with Escrow Holder by or on behalf of Buyer
under Paragraphs 5.1 and 5.2 above (collectively the "Deposit"), shall be
deposited by Escrow Holder in such State or Federally chartered bank as Buyer
may select and in such interest-bearing account or accounts as Escrow Holder
or Broker(s) deem appropriate and consistent with the timing requirements of
this transaction. The interest therefrom shall accrue to the benefit of
Buyer, who hereby acknowledges that there may be penalties or interest
forfeitures if the applicable instrument is redeemed prior to its specified
maturity.  Buyer's Federal Tax Identification Number is to be provided later.

6.  FINANCING CONTINGENCY.  (STRIKE IF NOT APPLICABLE)

    6.1  This offer is contingent upon Buyer obtaining from an insurance
company, bank, savings and loan association or other financial institution,
or from any correspondent or agent thereof, a commitment to lend to Buyer a
sum not less than $630,000.00 at a fixed interest rate not to exceed 10% per
annum, payable in equal monthly installments, including interest, amortized
over a period of not less than 20 years and all due in not less than 10
years, or at a variable interest rate commencing at an interest rate not to
exceed ___ per annum, amortized over a period of not less than ___  years and
all due in not less than ___ years, and in either case, with loan fees not to
exceed ___ of the amount of the new loan (the "New Loan").  The New Loan
shall be secured by a first deed of trust upon the Property and shall be upon
the following additional terms and conditions:  None other than above, and
upon such other terms and conditions as are usually required by such lender.

    6.2  Buyer hereby agrees to diligently pursue obtaining the New Loan.  If
Buyer shall fail to notify its Broker, Escrow Holder and Seller, in writing
within 60 days following the Date of Agreement, that the New Loan has not
been obtained, it shall be conclusively presumed that Buyer has either
obtained said New Loan or has waived this New Loan contingency.

    6.3  If, after due diligence, Buyer shall notify its Broker, Escrow
Holder and Seller, in writing, within the time specified in Paragraph 6.2
hereof, that Buyer has not obtained said new Loan, this Agreement shall be
terminated, and Buyer shall be entitled to the prompt return of Buyer's
Deposit and any other funds deposited by or for Buyer with Escrow Holder or
Seller, plus any interest earned thereon, less only Escrow Holder and Title
Company cancellation fees and costs, which Buyer shall pay.

7.  ESCROW AND CLOSING

    7.1  Upon acceptance hereof by Seller, this Agreement, including any
counter-offers incorporated herein by the Parties, shall constitute not only
the agreement of purchase and sale between Buyer and Seller, but also
instructions to Escrow Holder for the consummation of the Agreement through
the Escrow. Escrow Holder shall not


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prepare any further escrow instructions restating or amending this Agreement
unless specifically so instructed by the Parties of a Broker herein.

    7.2  Escrow Holder is hereby authorized and instructed to conduct the
Escrow in accordance with this Agreement, applicable law, custom and practice
of the community in which Escrow Holder is located, including any reporting
requirements of the Internal Revenue Code.  In the event of a conflict
between the law of the state where the Property is located and the law of the
state where the Escrow Holder is located, the law of the state where the
Property is located shall prevail.

    7.3  Subject to satisfaction of the contingencies herein described,
Escrow Holder shall close this escrow (the "Closing") by recording the grant
deed and other documents required to be recorded and by disbursing the funds
and documents in accordance with this Agreement.

    7.4  If this transaction is terminated for non-satisfaction and
non-waiver of a Buyer's Contingency, as defined in Paragraph 8.4, then
neither of the Parties shall thereafter have any liability to the other under
this Agreement, except to the extent of the breach of any affirmative
covenant or warranty in this Agreement that may have been involved.  In the
event of such termination, Buyer shall be promptly refunded all funds
deposited by or on behalf of Buyer with a Broker, Escrow Holder or Seller,
less only Title Company and Escrow Holder cancellation fees and costs, all of
which shall be Buyer's obligation.

    7.5  The Closing shall occur on the Expected Closing Date, or as soon
thereafter as the Escrow is in condition for Closing; provided, however, that
if the Closing does not occur by the Expected Closing Date and the Expected
Closing Date is not extended by mutual instructions of the Parties, a Party
hereto not then in default under this Agreement may notify the other Party,
Escrow Holder, and Broker(s) in writing that, unless the Closing occurs
within five (5) business days following said notice, the Escrow and this
Agreement shall be deemed terminated without further notice or instructions.

    7.6  Should the Closing not occur during said five (5) day period, this
Agreement and Escrow shall be deemed terminated and Escrow Holder shall
forthwith return all monies and documents, less only Escrow Holder's
reasonable fees and expenses, to the Party who deposited them.  Such Party
shall indemnify and hold Escrow Holder harmless in connection with such
return.  However, no refunds or documents shall be returned to a party
claimed by written notice to Escrow Holder to be in default under this
Agreement.

    7.7  Except as otherwise provided herein, the termination of Escrow and
this Agreement and/or the return of deposited funds or documents shall not
relieve or release either Buyer or Seller from any obligation to pay Escrow
Holder's fees and costs or constitute a waiver, release or discharge of any
breach or default that has occurred in the performance of the obligations,
agreements, covenants or warranties contained herein.

    7.8  If this Agreement terminates for any reason other than Seller's
breach or default, then at Seller's request, and as a condition to the return
of Buyer's deposit, Buyer shall within five (5) days after written request
deliver to Seller, at no charge, copies of all surveys, engineering studies,
soil reports, maps, master plans, feasibility studies and other similar items
prepared by or for Buyer that pertain to the Property.

8.  CONTINGENCIES TO CLOSING.

    8.1  The Closing of this transaction is contingent upon the satisfaction
or waiver of the following contingencies:


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         (a)  DISCLOSURE.  Buyer's receipt and written approval, within ten
(10) days after delivery to Buyer, of a completed Property Information Sheet
(the "Property Information Sheet"), concerning the Property, duly executed by
or on behalf of Seller in the current form or equivalent to that published
by the American Industrial Real Estate Association (the "A.I.R.").  Seller
shall provide Buyer with the Property Information Sheet within ten (10) days
following the Date of Agreement.

         (b)  PHYSICAL INSPECTION.  Buyer's written approval, within ten (10)
days following the later of the Date of Agreement or receipt by Buyer of the
Property Information Sheet, of an inspection by Buyer, at Buyer's expense, of
the physical aspects of the Property.

         (c)  HAZARDOUS SUBSTANCE CONDITIONS REPORT.  Buyer's written
approval, within thirty (30) days following the later of the Date of
Agreement or receipt by Buyer of the Property Information Sheet, of a
Hazardous Substance Conditions report concerning the Property and relevant
adjoining properties.  Such report will be obtained at Buyer's direction and
expense.  A "Hazardous Substance" for purposes of this Agreement is defined
as any substance whose nature and/or quantity of existence, use, manufacture,
disposal or effect, render it subject to Federal, state or local regulation,
investigation, remediation or removal as potentially injurious to public
health or welfare.  A "Hazardous Substance Condition" for purposes of this
Agreement is defined as the existence on, under or relevantly adjacent to the
Property of a Hazardous Substance that would require remediation and/or
removal under applicable Federal, state or local law.

         (d)  SOIL INSPECTION.  Buyer's written approval, within thirty (30)
days after the later of the Date of Agreement or receipt by Buyer of the
Property Information Sheet, of a soil test report concerning the Property.
Said report shall be obtained at Buyer's direction and expense.  Seller shall
promptly provide to Buyer copies of any existing soils reports that Seller
may have.

         (e)  CONDITION OF TITLE.  Buyer's written approval of a current
preliminary title report concerning the Property (the "PTR") issued by the
Title Company, as well as all documents (the "Underlying Documents") referred
to in the PTR, and the issuance by the Title Company of the title policy
described in Paragraph 9.1.  Seller shall cause the PTR and all Underlying
Documents to be delivered to Buyer promptly after the Date of Agreement.
Buyer's approval is to be given within ten (10) days after receipt of said
PTR and legible copies of all Underlying Documents.  The disapproval by Buyer
of any monetary encumbrance, which by the terms of this Agreement is not to
remain against the Property after the Closing, shall not be considered a
failure of this condition, as Seller shall have the obligation, at Seller's
expense, to satisfy and remove such disapproved monetary encumbrance at or
before the Closing.

         (f)  SURVEY.  Buyer's written approval, within thirty (30) days
after receipt of the PTR and Underlying Documents, of an ALTA title
supplement based upon a survey prepared to American Land Title Association
(the "ALTA") standards for an owner's policy by a licensed surveyor, showing
the legal description and boundary lines of the Property, any easements of
record, and any improvements, poles, structures, and things located within
ten feet (10') either side of the Property boundary lines.  The survey shall
be prepared at Buyer's direction and expense.  If Buyer has obtained a survey
and approved the ALTA title supplement, Buyer may elect within the period
allowed for Buyer's approval of a survey to have an ALTA extended coverage
owner's form of title policy, in which event Buyer shall pay any additional
premium attributable thereto.

         (g)  EXISTING LEASES AND TENANCY STATEMENTS.  Buyer's written
approval, within ten (10) days after receipt of legible copies of all leases,
subleases or rental arrangements (collectively, the "Existing Leases")
affecting the Property, and a statement (the "Tenancy Statement") in the
latest form or equivalent to that published

                                        -5-

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by the A.I.R., executed by Seller and each tenant and subtenant of the
Property.  Seller shall use its best efforts to provide Buyer with said
Existing Leases and Tenancy Statements promptly after the Date of Agreement.

         (h)  OTHER AGREEMENTS.  Buyer's written approval, within ten (10)
days after receipt, of a copy of any other agreements ("Other Agreements")
known to Seller that will affect the Property beyond the Closing.  Seller
shall cause said copies to be delivered to Buyer promptly after the Date of
Agreement.

         (i)  FINANCING.  If Paragraph 6 hereof dealing with a financing
contingency has not been stricken, the satisfaction or waiver of such New
Loan contingency.

         (j)  EXISTING NOTES.  If Paragraph 4.1(c) has not been stricken,
Buyer's written approval, within ten (10) days after receipt, of conformed
and legible copies of the Existing Notes, Existing Deeds of Trust and related
agreements (collectively, the "Loan Documents") to which the Property will
remain subject after the Closing, including a beneficiary statement (the
"Beneficiary Statement") executed by the holders of the Existing notes
confirming: (1) the amount of the unpaid principal balance, the current
interest rate, and the date to which interest is paid, and (2) the nature and
amount of any impounds held by the beneficiary in connection with said loan.
Seller shall use its best efforts to provide Buyer with said Loan Documents
and Beneficiary Statement promptly after the Date of Agreement.  Buyer's
obligation to close is further conditioned upon Buyer's being able to
purchase the Property without acceleration or change in the terms of any
Existing Notes or charges to Buyer except as otherwise provided by this
Agreement or approved by Buyer, provided, however, Buyer shall pay the
transfer fee referred to in Paragraph 4.2 hereof.

         (k)  DESTRUCTION, DAMAGE OR LOSS.  There shall not have occurred
prior to the Closing, a destruction of, or damage or loss to, the Property or
any portion thereof, from any cause whatsoever, which would cost more than
$10,000.00 to repair or cure.  If the cost of repair or cure is $10,000.00 or
less Seller shall repair or cure the loss prior to the Closing.  Buyer shall
have the option, within ten (10) days after receipt of written notice of a
loss costing more than $10,000.00 to repair or cure, to either terminate this
transaction or to purchase the Property notwithstanding such loss, but
without deduction or offset against the Purchase Price. If the cost to repair
or cure is more than $10,000.00, and Buyer does not elect to terminate this
transaction, Buyer shall be entitled to any insurance proceeds applicable to
such loss. Unless otherwise notified in writing by either Party or Broker,
Escrow Holder shall assume no destruction, damage or loss costing more than
$10,000.00 to repair or cure has occurred prior to Closing.

         (l)  MATERIAL CHANGE.  No Material Change, as hereinafter defined,
shall have occurred with respect to the Property that has not been approved
in writing by Buyer.  For purposes of this Agreement, a "Material Change"
shall be a change in the status of the use, occupancy, tenants or condition
of the Property as reasonably expected by the Buyer, that occurs after the
date of this offer and prior to the Closing.  Buyer shall have ten (10) days
following receipt of written notice from any source of any such Material
Change within which to approve or disapprove same.  Unless otherwise notified
in writing by either Party or Broker, Escrow Holder shall assume that no
Material Change has occurred prior to the Closing.

         (m)  SELLER PERFORMANCE.  The delivery of all documents and the due
performance by Seller of each and every undertaking and agreement to be
performed by Seller under this Agreement.

         (n)  BREACH OF WARRANTY.  That each representation and warranty of
Seller herein be true and correct as of the Closing.  Escrow Holder shall
assume that this condition has been satisfied unless notified to the contrary
in writing by Buyer or Broker(s) prior to the Closing.

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         (o)  BROKER'S FEE.  Payment at the Closing of such Broker's Fee as
is specified in this Agreement or later written instructions to Escrow Holder
executed by Seller and Broker(s).  It is agreed by Buyer, Seller and Escrow
Holder that Broker(s) is/are a third party beneficiary of this Agreement
insofar as the Broker's fee is concerned, and that no change shall be made by
Buyer, Seller or Escrow Holder with respect to the time of payment, amount of
payment, or the conditions to payment of the Broker's fee specified in this
Agreement, without the written consent of Broker(s).

    8.2  All of the contingencies specified in Subparagraphs (a) through (n)
of Paragraph 8.1 are for the benefit of, and may be waived by, Buyer, and may
be elsewhere herein referred to as "Buyer Contingencies."

    8.3  If Buyer shall fail, within the applicable time specified, to
approve or disapprove in writing to Escrow Holder, Seller and the other
Party's Broker(s), any item, matter or document subject to Buyer's approval
under the terms of this Agreement, it shall be conclusively presumed that
Buyer has approved such item, matter or document.  Buyer's conditional
approval shall constitute a disapproval, unless provision is made by Seller
within the time specified therefor by the Buyer in the conditional approval,
or by this Agreement, whichever is later, for the satisfaction of the
condition imposed by the Buyer.

    8.4  If any Buyer's Contingency is not satisfied, or if Buyer disapproves
any matter subject to its approval within the time period applicable thereto
("Disapproved Item"), Seller shall have the right within ten (10) days
following the expiration of the time period applicable to such Buyer
Contingency or receipt of notice of Buyer's disapproval, as the case may be,
to elect to cure such Disapproved Item prior to the Expected Closing Date
("Seller's Election"). Seller's failure to give to Buyer within said ten (10)
day period, written notice of Seller's commitment to cure such Disapproved
Item on or before the Expected Closing Date shall be conclusively presumed to
be Seller's Election not to cure such Disapproved Item.  If Seller elects,
either by written notice or failure to give written notice, not to cure a
Disapproved Item, Buyer shall have the election, within ten (10) days after
Seller's election, to either accept title to the Property subject to that
Disapproved Item, or to terminate this transaction.  Buyer's failure to elect
termination by written notice to Seller within said ten (10) day period shall
constitute Buyer's election to accept title to the Property subject to that
Disapproved Item without deduction or offset.  Unless expressly provided
otherwise herein, Seller's right to cure shall not apply to Hazardous
Substance Conditions referenced in Paragraph 8.1(c) or to the Financing
Contingency set forth in Paragraph 6.  Unless the parties mutually instruct
otherwise, if the time periods for the satisfaction of contingencies or for
Seller's and Buyer's said Elections would expire on a date after the Expected
Closing Date, the expected Closing Date shall be deemed extended to coincide
with the expiration of three (3) business days following the expiration of:
(a) the applicable contingency period(s); (b) the period within which Seller
may elect to cure the Disapproved Item; or (c) if Seller elects not to cure,
the period within which Buyer may elect to terminate this transaction,
whichever is later.

    8.5  Buyer understands and agrees that until such time as all Buyer's
Contingencies have been satisfied or waived, Seller and/or its agents may
solicit, entertain and/or accept back-up offers to purchase the subject
Property in the event the transaction covered by this Agreement is not
consummated.

    8.6  As defined in Subparagraph 8.1(c), Buyer and Seller acknowledge that
extensive local, state and Federal legislation establish broad liability upon
owners and/or users of real property for the investigation and remediation of
a Hazardous  Substance Condition.  The determination of the existence of a
Hazardous Substance Condition and the evaluation of the impact of such a
condition are highly technical and beyond the expertise of Broker(s).  Buyer
and Seller acknowledge that they have been advised by Broker(s) to consult
their own technical and legal experts with respect to the possible Hazardous
Substance Condition aspects of this Property or adjoining properties, and
Buyer and Seller are not relying upon any investigation by or statement of
Broker(s) with respect

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thereto.  Buyer and Seller hereby assume all responsibility for the impact of
such Hazardous Substance Conditions upon their respective interests herein.

9.  DOCUMENTS REQUIRED AT CLOSING.

    9.1  Escrow Holder shall cause to be issued to Buyer a standard coverage
(or ALTA extended, if so elected under Paragraph 8.1(f)) owner's form policy
of title insurance effective as of the Closing, issued by the Title Company
in the full amount of the Purchase Price, insuring title to the Property
vested in Buyer, subject only to the exceptions approved by Buyer.  In the
event there is a Purchase Money Deed of Trust in this transaction, the policy
of title insurance shall be a joint protection policy insuring both Buyer and
Seller.

    9.2  Seller shall deliver or cause to be delivered to Escrow Holder in
time for delivery to Buyer at the Closing, an original ink-signed:

         (a)  Grant deed (or equivalent), duly executed and in recordable
form, conveying fee title to the  Property to Buyer.

         (b)  If Paragraph 4.1(c) has not been stricken, the Beneficiary
Statements concerning Existing Note(s).

         (c)  If applicable, the Existing Leases and Other Agreements
together with duly executed assignments thereof by Seller and Buyer.  The
assignment of Existing Leases shall be on the most recent Assignment and
Assumption of Lessor's Interest in Lease form published by the A.I.R. or its
equivalent.

         (d)  If applicable, the Tenancy Statements executed by Seller and
the Tenant(s) of the Property.

         (e)  An affidavit executed by Seller to the effect that Seller is
not a "foreign person" within the meaning of Internal Revenue Code Section
1445 or successor statutes.  If Seller does not provide such affidavit in
form reasonably satisfactory to Buyer at least three (3) business days prior
to the Closing, Escrow Holder shall at the Closing deduct from Seller's
proceeds and remit to Internal Revenue Service such sum as is required by
applicable Federal law with respect to purchases from foreign sellers.

    9.3  Buyer shall deliver or cause to be delivered to Seller through
escrow:

         (a)  The cash portion of the Purchase Price and such additional sums
as are required of Buyer under this Agreement for prorations, expenses and
adjustments.  The balance of the cash portion of the Purchase Price,
including Buyer's escrow charges and other cash charges, if any, shall be
deposited by Buyer with Escrow Holder, by cashier's check drawn upon a local
major banking institution, federal funds wire transfer, or any other method
acceptable to Escrow Holder as immediately collectable funds, no later than
11:00 A.M. on the business day prior to the Expected Closing Date.

         (b)  If a Purchase Money Note and Purchase Money Deed of Trust are
called for by this Agreement, the duly executed originals of those documents,
the Purchase Money Deed of Trust being in recordable form, together with
evidence of fire insurance on the improvements in the amount of the full
replacement cost naming Seller as a mortgage loss payee, and a real estate
tax service contract (at Buyer's expense), assuring Seller of notice of the
status of payment of real property taxes during the life of the Purchase
Money Note.

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         (c)  The assumption portion of the Assignment and Assumption of
Lessor's Interest In Lease form specified in Paragraph 9.2(c) above, duly
executed by Buyer with respect to the obligations of the Lessor accruing
after the Closing as to each Existing Lease.

         (d)  Assumptions duly executed by Buyer of the obligations of Seller
that accrue after Closing under any Other Agreements.

         (e)  If applicable, a written assumption duly executed by Buyer of
the loan documents with respect to Existing Notes.

10. PRORATIONS, EXPENSES AND ADJUSTMENTS.

    10.1 TAXES.  Real property taxes payable by the owner of the Property
shall be prorated through Escrow as of the date of the Closing, based upon
the latest tax bill available.  The Parties agree to prorate, as of the
Closing, any taxes assessed against the Property by supplemental bill levies
by reason of events occurring prior to the Closing.  Payment shall be made
promptly in cash upon receipt of a copy of any such supplemental bill of the
amount necessary to accomplish such proration.

    10.2 INSURANCE.  If Buyer elects to take an assignment of the existing
casualty and/or liability insurance that is maintained by Seller, the current
premium therefor shall be prorated through Escrow as of the date of Closing.

    10.3 RENTALS, INTEREST AND EXPENSES.  Collected rentals, interest on
Existing Notes, utilities, and operating expenses shall be prorated as of the
date of Closing.  The Parties agree to promptly adjust between themselves,
outside of Escrow, any rents received after the Closing.

    10.4 SECURITY DEPOSIT.  Security Deposits held by Seller shall be given
to Buyer by a credit to the cash required of Buyer at the Closing.

    10.5 POST CLOSING MATTERS.  Any item to be prorated that is not
determined or determinable at the Closing shall be promptly adjusted by the
Parties by appropriate cash payment outside of the Escrow when the amount due
is determined.

    10.6 VARIATIONS IN EXISTING NOTE BALANCES.  In the event that Buyer is
taking title to the Property subject to an Existing Deed of Trust(s), and in
the event that a Beneficiary Statement as to the applicable Existing Note(s)
discloses that the unpaid principal balance of such Existing Note(s) at the
Closing will be more or less than the amount set forth in paragraph 4.1(c)
hereof (the Existing Note Variation), then the Purchase Money Note(s) shall
be reduced or increased by an amount equal to such Existing Note Variation.
If there is to be no Purchase Money Note, the cash required at the Closing
per Paragraph 4.1(a) shall be reduced or increased by the amount of such
Existing Note Variation.

    10.7 VARIATIONS IN NEW LOAN BALANCE.  In the event Buyer is obtaining a
New Loan and in the event that the amount of the New Loan actually obtained
is greater than the amount set forth in Paragraph 6.1 hereof, the Purchase
Money Note, if one is called for in this transaction, shall be reduced by the
excess of the actual face amount of the New Loan over such amount as
designated in Paragraph 6.1 hereof.

                                        -9-
<PAGE>


11. REPRESENTATION AND WARRANTIES OF SELLER AND DISCLAIMER.

    11.1 Seller's warranties and representations shall survive the Closing
and delivery of the deed, and, unless otherwise noted herein, are true,
material and relied upon by Buyer and Broker(s) in all respects, both as of
the Date of Agreement, and as of the date of Closing.  Seller hereby makes
the following warranties and representations to Buyer and Broker(s):

         (a)  AUTHORITY OF SELLER.  Seller is the owner of the Property
and/or has the full right, power and authority to sell, convey and transfer
the Property to Buyer as provided herein, and to perform Seller's obligations
hereunder.

         (b)  MAINTENANCE DURING ESCROW AND EQUIPMENT CONDITION AT CLOSING.
Except as otherwise provided in Paragraph 7.1(k) hereof dealing with
destruction, damage or loss, Seller shall maintain the Property until the
Closing in its present condition, ordinary wear and tear excepted.  The
heating, ventilating, air conditioning, plumbing, loading doors and
electrical systems shall be in good operating order and condition at the time
of Closing.

         (c)  HAZARDOUS SUBSTANCES/STORAGE TANKS.  Seller has no knowledge,
except as otherwise disclosed to Buyer in writing, of the existence or prior
existence on the Property of any Hazardous Substance (as defined in Paragraph
8.1(c)), nor of the existence or prior existence of any above or below ground
storage tank or tanks.

         (d)  COMPLIANCE.  Seller has no knowledge of any aspect or condition
of the Property which violates applicable laws, rules, regulations, codes, or
covenants, conditions or restrictions, or of improvements or alterations made
to the Property without a permit where one was required, or of any
unfulfilled order or directive of  any applicable governmental agency or
casualty insurance company, that any work of investigation, remediation,
repair, maintenance or improvement is to be performed on the Property.

         (e)  CHANGES IN AGREEMENTS.  Prior to the Closing, Seller will not
violate or modify, orally or in writing, any Existing Lease or Other
Agreement, or create any new leases or other agreements affecting the
Property, without Buyer's written approval, which approval will not be
unreasonably withheld.

         (f)  POSSESSORY RIGHTS.  Seller has no knowledge that anyone will,
at the Closing, have any right to possession of the Property, except as
disclosed by this Agreement or otherwise in writing to Buyer.

         (g)  MECHANICS' LIENS.  There are no unsatisfied mechanics' or
materialmans' lien rights concerning the Property.

         (h)  ACTIONS, SUITS OR PROCEEDINGS.  Seller has no knowledge of any
actions, suits or proceedings pending or threatened before any commission,
board, bureau, agency, instrumentality, arbitrator(s) court or tribunal that
would affect the Property or the right to occupy or utilize same.

         (i)  NOTICE OF CHANGES.  Seller will promptly notify Buyer and
Broker(s) in writing of any Material Change (as defined in Paragraph 8.1(l))
affecting the Property that becomes known to Seller prior to the Closing.

         (j)  NO TENANT BANKRUPTCY PROCEEDINGS.  Seller is not the subject of
a bankruptcy or insolvency proceeding.


                                        -10-

<PAGE>

         (k)  NO SELLER BANKRUPTCY PROCEEDINGS.  Seller is not the subject of
a bankruptcy, insolvency or probate proceeding.

    11.2 Buyer hereby acknowledges that, except as otherwise stated in this
Agreement, Buyer is purchasing the Property in its existing condition and
will, by the time called for herein, make or have waived all inspections of
the Property Buyer believes are necessary to protect its own interest in and
its contemplated use of, the Property.  The Parties acknowledge that, except
as otherwise stated in this Agreement, no representations, inducements,
promises, agreements, assurances, oral or written, concerning the Property,
or any aspect of the Occupational Safety and Health Act, hazardous substance
laws, or any other act, ordinance or law, have been made by either Party or
Broker, or relied upon by either Party hereto.

12. POSSESSION.

    12.1 Possession of the Property shall be given to Buyer at the Closing
subject to the rights of tenants under Existing Leases.

13. BUYERS' ENTRY.

    13.1 At any time during the Escrow period, Buyer, and its agents and
representatives, shall have the right at reasonable times and subject to
rights of tenants under Existing Leases, to enter upon the Property for the
purpose of making inspections and tests specified in this Agreement.
Following any such entry or work, unless otherwise directed in writing by
Seller, Buyer shall return the Property to the condition it was in prior to
such entry or work, including the recompaction or removal of any disrupted
soil or material as Seller may reasonably direct.  All such inspections and
tests and any other work conducted or materials furnished with respect to the
Property by or for Buyer shall be paid for by Buyer as and when due and Buyer
shall indemnify, defend, protect and hold harmless Seller and the Property of
and from any and all claims, liabilities, demands, losses, costs, expenses
(including reasonable attorneys' fees), damages or recoveries, including
those for injury to person or property, arising out of or relating to any
such work or materials or the acts or omissions of Buyer, its agents or
employees in connection therewith.

14. FURTHER DOCUMENTS AND ASSURANCES.

    14.1 Buyer and Seller shall each, diligently and in good faith, undertake
all actions and procedures reasonably required to place the Escrow in
condition for Closing as and when required by this Agreement.  Buyer and
Seller agree to provide all further information, and to execute and deliver
all further documents and instruments, reasonably required by Escrow Holder
or the Title Company.

15. ATTORNEYS' FEES.

    15.1 In the event of any litigation or arbitration between the Buyer,
Seller, and Broker(s), or any of them, concerning this transaction, the
prevailing party shall be entitled to reasonable attorneys' fees and costs.
The attorneys' fee award shall not be computed in accordance with any court
fee schedule, but shall be such as to fully reimburse all attorneys fees
reasonably incurred in good faith.

16. PRIOR AGREEMENTS/AMENDMENTS.

    16.1 The contract in effect as of the Date of Agreement supersedes any
and all prior agreements between Seller and Buyer regarding the Property.

                                        -11-
<PAGE>

    16.2 Amendments to this Agreement are effective only if made in writing
and executed by Buyer and Seller.

17. BROKER'S RIGHTS.

    17.1 If this sale shall not be consummated due to the default of Buyer,
the Buyer shall not be liable to and shall not have to pay to Broker(s) the
commission that Broker(s) would have received had the sale been consummated.
This obligation of Buyer is not in addition to any obligation with respect to
liquidated damages.

    17.2 Upon the Closing, Broker(s) is/are authorized to publicize the facts
of this transaction.

18. NOTICES.

    18.1 Whenever any Party hereto, Escrow Holder or Broker(s) herein shall
desire to give or serve any notice, demand, request, approval, or other
communication, each such communication shall be in writing, and delivered
personally by messenger or by mail, postage prepaid addressed as set forth
adjacent to that partys' or Brokers' signature on this Agreement or by
telecopy with receipt confirmed by telephone.  Service of any such
communication shall be deemed made on the date of actual receipt at such
address.

    18.2 Any Party or Broker hereto may from time to time by notice in
writing served upon the other Party as aforesaid designate a different
address to which or a different person or additional persons to whom all
communications are thereafter to be made.

19. DURATION OF OFFER.

    19.1 If this offer shall not be accepted by Seller on or before 5:00 P.M.
according to the time standard applicable to the city of Pleasanton, on the
date of December 18, 1996, it shall be deemed automatically revoked.

    19.2 The acceptance of this offer or of any subsequent counter-offer
hereto that creates an agreement between the Parties as described in
Paragraph 1.2 shall be deemed made upon delivery to the other Party or either
Broker herein of a duly executed writing unconditionally accepting the last
outstanding offer or counter-offer.

20. LIQUIDATED DAMAGES.  (THIS LIQUIDATED DAMAGES PARAGRAPH IS APPLICABLE
ONLY IF INITIALED BY BOTH PARTIES).

    20.1 THE PARTIES AGREE THAT IT WOULD BE IMPRACTICABLE OR EXTREMELY
DIFFICULT TO FIX, PRIOR TO SIGNING THIS AGREEMENT, THE ACTUAL DAMAGES WHICH
WOULD BE SUFFERED BY SELLER IF BUYER FAILS TO PERFORM ITS OBLIGATIONS UNDER
THIS AGREEMENT.  THEREFORE, IF, AFTER THE SATISFACTION OR WAIVER OF ALL
CONTINGENCIES PROVIDED FOR THE BUYER'S BENEFIT, BUYER BREACHES THIS
AGREEMENT, SELLER SHALL BE ENTITLED TO LIQUIDATED DAMAGES IN THE AMOUNT OF
$25,000 PLUS INTEREST, IF ANY, ACCRUED THEREON.  UPON PAYMENT OF SAID SUM TO
SELLER, BUYER SHALL BE RELEASED FROM ANY FURTHER LIABILITY TO SELLER, AND ANY
ESCROW CANCELLATION FEES AND TITLE COMPANY CHARGES SHALL BE PAID BY SELLER.

    Buyer Initials                               Seller Initials


                                        -12-

<PAGE>

21. ARBITRATION OF DISPUTES.  THIS ARBITRATION OF DISPUTES PARAGRAPH IS
APPLICABLE ONLY IF INITIALED BY BOTH PARTIES AND IS SUBJECT TO PARAGRAPH 22
BELOW).

    21.1 ANY CONTROVERSY AS TO WHETHER SELLER IS ENTITLED TO THE LIQUIDATED
DAMAGES AND/OR BUYER IS ENTITLED TO THE RETURN OF DEPOSIT MONEY, SHALL BE
DETERMINED BY BINDING ARBITRATION BY, AND UNDER THE COMMERCIAL RULES (the
"COMMERCIAL RULES") OF, THE AMERICAN ARBITRATION ASSOCIATION.  HEARINGS ON
SUCH ARBITRATION SHALL BE HELD IN THE COUNTY WHERE THE PROPERTY IS LOCATED.
ANY SUCH CONTROVERSY SHALL BE ARBITRATED BY THREE (3) ARBITRATORS WHO SHALL
BE IMPARTIAL REAL ESTATE BROKERS WITH AT LEAST FIVE (5) FULL TIME YEARS OF
EXPERIENCE IN THE AREA WHERE THE PROPERTY IS LOCATED, IN THE TYPE OF REAL
ESTATE THAT IS THE SUBJECT OF THIS AGREEMENT AND SHALL BE APPOINTED UNDER THE
COMMERCIAL RULES. THE ARBITRATORS SHALL HEAR AND DETERMINE SAID CONTROVERSY
IN ACCORDANCE WITH APPLICABLE LAW AND THE INTENTION OF THE PARTIES AS
EXPRESSED IN THIS AGREEMENT, AS THE SAME MAY HAVE BEEN DULY MODIFIED IN
WRITING BY THE PARTIES PRIOR TO THE ARBITRATION, UPON THE EVIDENCE PRODUCED
AT AN ARBITRATION HEARING SCHEDULED AT THE REQUEST OF EITHER PARTY.  SUCH
PRE-ARBITRATION DISCOVERY SHALL BE PERMITTED AS IS AUTHORIZED UNDER THE
COMMERCIAL RULES OR STATE LAW APPLICABLE TO ARBITRATION PROCEEDINGS.  THE
AWARD SHALL BE EXECUTED BY AT LEAST TWO (2) OF THE THREE (3) ARBITRATORS, BE
RENDERED WITHIN THIRTY (30) DAYS AFTER THE CONCLUSION OF THE HEARING, AND MAY
INCLUDE ATTORNEYS' FEES AND COSTS TO THE PREVAILING PARTY PER PARAGRAPH 15
HEREOF.  JUDGMENT MAY BE ENTERED ON THE AWARD IN ANY COURT OF COMPETENT
JURISDICTION NOTWITHSTANDING THE FAILURE OF A PARTY DULY NOTIFIED OF THE
ARBITRATION HEARING TO APPEAR THEREAT.

    21.2 BUYER'S RESORT TO OR PARTICIPATION IN SUCH ARBITRATION PROCEEDINGS
SHALL NOT BAR SUIT IN A COURT OF COMPETENT JURISDICTION BY THE BUYER FOR
DAMAGES AND/OR SPECIFIC PERFORMANCE UNLESS AND UNTIL THE ARBITRATION RESULTS
IN AN AWARD TO THE SELLER OF LIQUIDATION DAMAGES, IN WHICH EVENT SUCH AWARD
SHALL ACT AS A BAR AGAINST ANY ACTION BY BUYER FOR DAMAGES AND/OR SPECIFIC
PERFORMANCE.

    21.3 NOTICE BY INITIALING IN THE SPACE BELOW YOU ARE AGREEING TO HAVE ANY
DISPUTE ARISING OUT OF THE MATTERS INCLUDED IN THE "ARBITRATION OF DISPUTES"
PROVISION DECIDED BY NEUTRAL ARBITRATION AS PROVIDED BY CALIFORNIA LAW AND
YOU ARE GIVING UP ANY RIGHTS YOU MIGHT POSSESS TO HAVE THE DISPUTE LITIGATED
IN A COURT OR JURY TRIAL.  BY INITIALING IN THE SPACE BELOW YOU ARE GIVING UP
YOUR JUDICIAL RIGHTS TO DISCOVERY AND APPEAL, UNLESS SUCH RIGHTS ARE
SPECIFICALLY INCLUDED IN THE "ARBITRATION OF DISPUTES" PROVISION.  IF YOU
REFUSE TO SUBMIT TO ARBITRATION AFTER AGREEING TO THIS PROVISION, YOU MAY BE
COMPELLED TO ARBITRATE UNDER THE AUTHORITY OF THE CALIFORNIA CODE OF CIVIL
PROCEDURE.  YOUR AGREEMENT TO THIS ARBITRATION PROVISION IS VOLUNTARY.  WE
HAVE READ AND UNDERSTAND THE FOREGOING AND AGREE TO SUBMIT DISPUTES ARISING
OUT OF THE MATTERS INCLUDED IN THE "ARBITRATION OF DISPUTES" PROVISION TO
NEUTRAL ARBITRATION.

    Buyer Initials                               Seller Initials


                                        -13-

<PAGE>

22. APPLICABLE LAW.

    22.1 This Agreement shall be governed by, and Paragraph 21.3 amended to
refer to, the laws of the state in which the Property is located.

23. TIME OF ESSENCE.

    23.1 Time is of the essence of this Agreement.

24. COUNTERPARTS.

    24.1 This Agreement may be executed by Buyer and Seller in counterparts,
each of which shall be deemed an original, and all of which together shall
constitute one and the same instrument.  Escrow Holder, after verifying that
the counterparts are identical except for the signatures, is authorized and
instructed to combine the signed signature pages on one of the counterparts,
which shall then constitute the Agreement.

25. DISCLOSURES REGARDING THE NATURE OF A REAL ESTATE AGENCY RELATIONSHIP.

    25.1 The Parties and Broker(s) agree that their relationship(s) shall be
governed by the principles set forth in California Civil Code, Section 2375,
as summarked in the following Paragraph 25.2.

    25.2 When entering into a discussion with a real estate agent regarding a
real estate transaction, a Buyer or Seller should from the outset understand
what type of agency relationship or representation it has with the agent or
agents in the transaction.  Buyer and Seller acknowledge being advised by the
Broker(s) in this transaction, as follows:

           (a)  SELLER'S AGENT.  A Seller's agent under a listing agreement
with the Seller acts as the agent for the Seller only.  A Seller's agent or
subagent has the following affirmative obligations: (1) TO THE SELLER: A
fiduciary duty of utmost care, integrity, honesty, and loyalty in dealings
with the Seller. (2) TO THE BUYER AND THE SELLER: (a) Diligent exercise of
reasonable skill and care in performance of the agent's duties, (b) A duty of
honest and fair dealing and good faith, (c) A duty to disclose all facts
known to the agent materially affecting the value or desirability of the
property that are not known to, or within the diligent attention and
observation of, the Parties.  An agent is not obligated to reveal to either
Party any confidential information obtained from the other Party which does
not involve the affirmative duties set forth above.

         (b)  BUYER'S AGENT.  A selling agent can, with a Buyer's consent,
agree to act as agent for the Buyer only.  In these situations, the agent is
not the Seller's agent, even if by agreement the agent may receive
compensation for services rendered, either in full or in part from the
Seller.  An agent acting only for a Buyer has the following affirmative
obligations. (1) TO THE BUYER: A fiduciary duty of utmost care, integrity,
honesty, and loyalty in dealings with the Buyer. (2) TO THE BUYER AND THE
SELLER: (a) Diligent exercise of reasonable skill and care in performance of
the agent's duties, (b) A duty of honest and fair dealing and good faith (c)
A duty to disclose all facts known to the agent materially affecting the
value or desirability of the property that are not known to, or within the
diligent attention and observation of, the Parties.  An agent is not
obligated to reveal to either Party any confidential information obtained
from the other Party which does not involve the affirmative duties set forth
above.

         (c)  AGENT REPRESENTING BOTH SELLER AND BUYER.  A real estate agent,
either acting directly or through one or more associate licenses, can legally
be the agent of both the Seller and the Buyer in a transaction, but only with
the knowledge and consent of both the Seller and the Buyer. (1) in a dual
agency situation, the agent has the following affirmative obligations to both
the Seller and the Buyer: (a) A fiduciary duty of utmost care, integrity,

                                        -14-
<PAGE>

honesty and loyalty in the dealings with either Seller or the Buyer, (b)
Other duties to the Seller and the Buyer as stated above in their respective
sections (a) or (b) of this paragraph 25.2 (2).  In representing both Seller
and Buyer, the agent may not without the express permission of the respective
Party, disclose to the other Party that the Seller will accept a price less
than the listing price or that the Buyer will pay a price greater than the
price offered.  (3) The above duties of the agent in a real estate
transaction do not relieve a Seller or Buyer from the responsibility to
protect their own interests.  Buyer and Seller should carefully read all
agreements to assure that they adequately express their understanding of the
transaction.  A real estate agent is a person qualified to advise about real
estate.  If legal or tax advice is desired, consult a competent professional.

         (d)  FURTHER DISCLOSURES.  Throughout this transaction Buyer and
Seller may receive more than one disclosure, depending upon the number of
agents assisting in the transaction.  Buyer and Seller should each read its
contents each time it is presented, considering the relationship between them
and the real estate agent in this transaction and that disclosure.

    25.3 CONFIDENTIAL INFORMATION.  Buyer and Seller agree to identify to
Broker(s) as "Confidential" any communication or information given Broker(s)
that is considered by such Party to be confidential.

26. ADDITIONAL PROVISIONS:

    Additional provisions of this offer, if any, are as follows or are
attached hereto by an addendum consisting of paragraphs "A" through "K".  (It
will be presumed no other provisions are included unless specified here.)
Addendums "A" and Exhibit "A" and "B" are attached hereby made a part of this
Lease.
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

BUYER AND SELLER HEREBY ACKNOWLEDGED THAT THEY HAVE BEEN AND ARE NOW BY THE
BROKER(S) TO CONSULT AND RETAIN THEIR OWN EXPERTS TO ADVISE AND REPRESENT
THEM CONCERNING THE LEGAL AND INCOME TAX EFFECTS OF THIS AGREEMENT, AS WELL
AS THE CONDITION AND/OR LEGALITY OF THE PROPERTY, THE IMPROVEMENTS, AND
EQUIPMENT THEREIN, THE SOIL THEREOF, THE CONDITION OF TITLE THERETO, THE
SURVEY THEREOF, THE ENVIRONMENTAL ASPECTS THEREOF, THE EXISTENCE AND NATURE
OF TENANCIES THEREIN, THE OUTSTANDING OTHER AGREEMENTS, IF ANY, WITH RESPECT
THERETO, AND THE EXISTING OR CONTEMPLATED FINANCING THEREOF, AND THAT THE
BROKER(S) IS/ARE NOT TO BE RESPONSIBLE FOR PURSUING THE INVESTIGATION OF ANY
SUCH MATTERS UNLESS EXPRESSLY OTHERWISE AGREED TO IN WRITING BY BROKER(S) AND
BUYER OR SELLER.

              THIS FORM IS NOT FOR USE IN CONNECTION WITH
              THE SALE OF  RESIDENTIAL PROPERTY.

If this Agreement has been filled in, it has been prepared for submission to
your attorney for his approval.  No representation of recommendation is made
by the real estate Broker(s) or their agents or employees as to the legal

                                        -15-

<PAGE>

sufficiency, legal effect, or tax consequences of this Agreement or the
transaction involved herein.  The undersigned Buyer offers and agrees to buy
the Property on the terms and conditions stated and acknowledges receipt of a
copy hereof.

BROKER:                           BUYER:  Supergen, Inc.

By:      Lee & Associates C.R.E.S.               By:  /s/ Hank Settle
   -----------------------------------------        ---------------------------
Date:                                            By:
     ---------------------------------------        ---------------------------
Name Printed:      Bob Kumnick                   Name Printed:  Hank Settle
             -------------------------------                  -----------------
Title:   Principal                               Title: Chief Financial Officer
      --------------------------------------           ------------------------
Address: 5960 Stoneridge Drive, Suite 101        Address: 6450 Hollis Street
        ------------------------------------             ----------------------
         Pleasanton, CA 94588                             Emeryville, CA 94608
        ------------------------------------             ----------------------
Telephone:    (510) 460-6200                      Telephone:  (510) 655-1075
          ----------------------------------                -------------------
Telecopier:   (510) 460-6210                      Telecopier: (510) 655-1098
          ----------------------------------                 ------------------

27. ACCEPTANCE.

    27.1 Seller accepts the foregoing offer to purchase the Property and hereby
agrees to sell the Property to Buyer on the terms and conditions therein
specified.

    27.2 Seller acknowledges that Broker(s) has/have been retained to locate a
Buyer and is/are the procuring cause of the purchase and sale of the Property
set forth in this Agreement. In consideration of real estate brokerage service
rendered by Broker(s), Seller agrees to pay Broker(s) a real estate brokerage
fee in a sum equal to six percent of the Purchase Price (the Broker(s) Fee)
divided equally in such shares as said Broker(s) shall direct in writing, As
us provided in paragraph 9.1(o), this Agreement shall serve as an irrevocable
instruction to Escrow Holder to pay such brokerage fee to Broker(s) out of the
proceeds accruing to the account of Seller at the Closing.

    27.3 Seller acknowledges receipt of a copy hereof and authorizes the
Broker(s) to deliver a signed copy to Buyer.

                                        -16-

<PAGE>


NOTE:  A PROPERTY INFORMATION SHEET IS REQUIRED TO BE DELIVERED TO BUYER BY
SELLER UNDER THIS AGREEMENT.
<TABLE>

<S>                                            <C>
BROKER:                                        SELLER:

By:   Lee & Associates C.R.E.S.                By:  The Ashwill Trust, established 11/8/89
   ------------------------------                 ---------------------------------
Date:                                          Date:   12-23-96
     ----------------------------                   -------------------------------
Name Printed:      Bob Kumnick                 Name Printed:  Ellwin E. Ashwill  /s/ Ellwin E. Ashwill
             --------------------                           ------------------------------------------
Title:   Principal                             Title:    Trustee
      ---------------------------                    ------------------------------
Address: 5960 Stoneridge Drive, Suite 101      Address: 725 Town & Country, Suite 140
        ----------------------------------            --------------------------------
          Pleasanton, CA 94588                           Orange, CA 92868
        ----------------------------------            --------------------------------
Telephone:    (510) 460-6200                   Telephone:     (510) 564-1632
          --------------------------------               -----------------------------
Telecopier:   (510) 469-6210                   Telecopier:    (510) 564-0505
          --------------------------------               -----------------------------

</TABLE>
                                        -17-

<PAGE>
                            ADDENDUM "A"


This Addendum is hereby made a part of the Standard Offer, Agreement, and
Escrow Instructions for Purchase of Real Estate, dated December 11, 1996, by
and between THE ASHWILL TRUST, ESTABLISHED NOVEMBER 8, 1989 ("Seller") and
SUPERGEN, INC. ("Buyer"), for the Premises located at 1059 Serpentine Lane,
Pleasanton, California.

    A.   Lessee to purchase the shell building (9,600 -plus or minus- sq.
         ft.) at 1059 Serpentine Lane, at SEVEN HUNDRED FORTY-FOUR
         THOUSAND AND NO/100 DOLLARS ($744,000.00) and close
         escrow upon approval of the Building Final Inspection of
         shell building from the City of Pleasanton.  Buyer will
         be responsible for loan costs and title company costs as
         outlined below:

         1.   Current non-delinquent city and country real estate taxes, and
              principal and interest on assessments shall be prorated between
              Buyer and Seller as of the close of escrow on the basis of a
              thirty (30) day month.

              Note:  Bonds and assessments of public record in the
              approximating total amount of ELEVEN THOUSAND SIX HUNDRED SIXTEEN
              ($11,616.00) as of October, 1996, which are a lien on the
              Property shall be assumed by Buyer.  The exact amount of
              assessments will be calculated by the City of Pleasanton at close
              of escrow and prorated accordingly.

         2.   Buyer agrees to pay for all escrow fees, recording fees, notary
              fees, and owner's and lender's title insurance policies.  Seller
              agrees to pay for the county transfer tax.  All other costs and
              expenses, if any, shall be borne by the respective parties in
              accordance with the custom in Alameda County prevailing at the
              Close of Escrow for similar transactions.

    B.   Deposits

         1.   TEN THOUSAND AND NO/100 DOLLARS ($10,000.00) to be deposited in
              escrow within five (5) days after mutual execution of Purchase
              and Sale Agreement.  Said deposit shall be placed by Escrow
              Company into an interest bearing account reasonably acceptable to
              both Buyer and Seller, with all interest accruing for the benefit
              of Buyer.

         2.   Buyer shall have forty-five (45) calendar days from the Opening
              of Escrow (the "Inspection Feasibility Period") within which to:
              (i) inspect any and all physical aspects of the Property,
              (ii) review existing zoning and other governmental regulations,
              (iii) review all title exceptions, and (iv) inspect and test
              soils, groundwater, and hazardous materials, if any.

              Buyer shall also have sixty (60) calendar days from the Opening
              of Escrow (the "Financing Contingency Period") to secure adequate
              financing.  Prior to the expiration of each Contingency Period,
              Buyer shall have the right to terminate the Purchase Agreement by
              delivering written notice of such election to Seller.  If Buyer
              elects not to proceed with the purchase of this property, Escrow
              Company shall return deposit to the Buyer.

              Seller further agrees to furnish Buyer with any and all existing
              soils, engineering, geologic and environmental studies completed
              by Seller to date on the Property, or adjacent properties, within
              ten (10) business days of the Opening of Escrow.

<PAGE>


         3.   A FIFTEEN THOUSAND AND NO/100 DOLLARS ($15,000.00) additional
              deposit to be entered into escrow upon removal or waiver of all
              contract contingencies (60 days from date of agreement).  At such
              time, all deposits to date (TWENTY-FIVE THOUSAND AND NO/100
              DOLLARS ($25,000)) will be released to the Seller and be
              applicable to the purchase price, but non-refundable to Buyer
              subject to Sellers receiving approval of Building Final
              Inspection from the City of Pleasanton on the shell building.
              Said approval shall be in substantial conformity with plans of
              record approved by Buyer and Seller.  Any items specified may be
              substituted with equal quality replacement or better.

    C.   Building Shell Defined

         The building proposed to be delivered in shell condition consisting of
         a single story, concrete tilt-up condominium building of approximately
         9,600 square feet.

         The common area ownership consists of approximately
         60,460 square feet of buildings on 167,793 -plus or
         minus- square feet of land. The condominium building
         located at 1059 Serpentine Lane shall be 15.9 percent of
         the total, as outlined in Exhibit "B" of the Covenants,
         Conditions & Restrictions of Serpentine Business Park.
         The buildings in the project have an average building to
         land coverage of thirty-six percent (36%).  A minimum of
         ten (10) designated asphalt paved parking spaces for this
         building will be provided with appropriate striping,
         subject to the City of Pleasanton approval.  The balance
         of the parking will be shared in common with the other
         building owners.  The total project will have a parking
         ratio of approximately 2.83 parking spaces per 1,000 -plus
         or minus- square feet of building.  Only address signage on
         buildings will be provided.  The landscaping plan is
         defined in the building plans.  A separate irrigation
         water meter common to the whole project is part of a
         fully automatic, zoned, landscaping irrigation system.
         The project has an appropriate storm drainage system and
         screened refuse areas.  All off-site work and utility
         connections, as defined below, shall be the
         responsibility of the Builder.

         The appropriate utilities, which include provision for electrical
         meter and private water meter, shall be stubbed out and capped on the
         exterior of the building by the Builder.  Telephone to be stubbed to
         the building.  The natural gas line shall be stubbed to the east
         exterior of the building located at 1059 Serpentine Lane.  The sewer
         line will be plumbed in the concrete floor of the building.  The
         electrical service will be 800 AMP, 120/208 volt, 3-phase power to the
         westerly exterior of the building.  The 800 AMP panel will not include
         a meter socket, nor a breaker.  However, a 100 AMP house panel will be
         supplied including a socket, meter and breaker.

         The building exterior will be painted, landscaped, have an interior
         fire sprinkler system.  No electrical power distribution will be
         provided within the building.  The interior warehouse walls will be
         painted.  There will be no insulation in the building.

         The building shall be weather tight, and have skylights, doors, and
         windows, as per building plans.


                                        -2-
<PAGE>

    D.   Close of Escrow

         The building shell will be completed by mid to late February 1997.

         Close of escrow shall be within three (3) days of Seller's receipt of
         approved Building Final Inspection from the City of Pleasanton of the
         shell building (estimated to be March 1, 1997).  If Buyer chooses to
         extend escrow after shell is complete, then Buyer will be obligated to
         pay Seller ONE HUNDRED SIXTY-THREE AND NO/100 DOLLARS ($163.00) per
         day until escrow closes.

         Buyer may commence building tenant improvements subject to the
         following:

         1.   All contingencies are removed.

         2.   Deposits (TWENTY-FIVE THOUSAND AND NO/100 DOLLARS ($25,000.00))
              are passed through to Seller.

         3.   Buyer has approved building permit for tenant improvements from
              the City of Pleasanton.

    E.   Buyer to read and approve CC&R's of Valley Business Park and
         Serpentine Business Park, by-laws, association financial information,
         preliminary title report, and any other information regarding property
         delivered by Seller within forty-five (45) calendar days of date of
         Agreement.

    F.   Seller herein has a valid California Real Estate Broker's license.

    G.   Disclosure:

         -    Seller herein is selling a building shell, located at 1059
              Serpentine Lane, City of Pleasanton;

         -    Buyer hereby acknowledges that any and all representation
              regarding square footage of unit is approximate, and pertains to
              industry standards.  For the purpose(s) of common area
              maintenance expense(s), pro rata and market comparables, the
              measurement to the BUILDING'S DRIP LINE has been used;

         -    Units are being sold on a total price for the unit, not a per
              square foot price.

    H.   Assignment Rights:  Buyer has the right to assign any rights to
         acquire the Property to an entity in which Buyer is principal.

    I.   Seller's Studies:  As soon as possible following the execution by
         Seller hereof, Seller shall deliver to Buyer copies of all information
         in Seller's possession relating to the Property to assist Buyer in its
         feasibility study.

    J.   It is the intent of the Ashwill Trust, Established November 8, 1989,
         to effect a tax deferred exchange in accordance with Section 1031 of
         the Internal Revenue Code.  Buyer agrees to cooperate fully for
         Seller's exchange and is to be at no additional expense or liability
         for same.

                                        -3-

<PAGE>


    K.   Seller represents and warrants that the building shell shall be
         designed and constructed in a workmanlike manner, consistent with the
         building plans approved by Buyer, and that they should be fit for the
         purposes for which they are intended.

All exceptions to the foregoing representations and warranties are listed below
(if there are no exceptions, write "No Exceptions".)

The building plans for the project and this Standard Offer, Agreement and
Escrow Instructions are intended to supplement each other so that any work
mentioned in one (1) instrument but not in the other shall be performed in
the same manner as if mentioned in both instruments.  If there is a conflict
or difference between the two (2) instruments, then the Standard Offer,
Agreement and Escrow Instructions shall prevail over the building plans.
Parking approved by the City of Pleasanton, shall be accepted by all parties
as the final approval.

UNDERSTOOD AND AGREED:

SELLER:                           BUYER:

THE ASHWILL TRUST,                SUPERGEN, INC.
ESTABLISHED NOVEMBER 8, 1989

BY: /s/ Ellwin E. Ashwill         BY:  /s/ Hank Settle
   -----------------------------     -----------------------------
      Ellwin E. Ashwill, Trustee           Hank Settle
DATE: 12-23-96                    DATE: December 19, 1996
    ----------------------------      ----------------------------

                                        -4-

<PAGE>

                            ADDENDUM "B"


This Addendum is hereby made a part of the Standard Offer, Agreement, and
Escrow Instructions for Purchase of Real Estate, dated December 11, 1996, by
and between THE ASHWILL TRUST, ESTABLISHED NOVEMBER 8, 1989 ("Seller") and
SUPERGEN, INC. ("Buyer"), for the Premises located at 1059 Serpentine Lane,
Pleasanton, California.

                      800 AMP Electrical Power
                      ------------------------

    It has been requested by Supergen, Inc. that Lessor install an 800 amp
electrical service in lieu of a 400 AMP service to the westerly exterior of
said building.  This has been requested by Supergen, Inc. prior to their due
diligence and before they have removed any of the contingencies, outlined in
the Standard Offer, Agreement and Escrow Instructions for Purchase of Real
Estate, dated December 11, 1996.  If Supergen, Inc. does not proceed and go
forward with the purchase of said building, Seller will be left with an
increased electrical service he does not want.  Accordingly, Buyer hereby
agrees to the following:

    1.   Seller shall install an 800 AMP service in lieu of a 400 AMP service
to the westerly exterior of said building.  The 800 AMP service shall not
include a meter socket, nor any breaker.  Seller shall include a 100 AMP
house service, breaker and meter socket; said 100 AMPs to be part of the 800
AMPs.

    2.   Buyer to release THREE THOUSAND AND NO/100 DOLLARS ($3,000.00) of
his deposit monies immediately to Seller in payment of difference in power
installation, applicable against the Purchase Price, but not refundable to
Buyer in the event Buyer cancels escrow for any reason whatsoever.

    3.   It is understood and part of the agreement that should Buyer cancel,
he automatically forfeits the Three Thousand and No/100 Dollars ($3,000.00)
portion of Buyer's deposit released to Seller.

UNDERSTOOD AND AGREED:

SELLER:                           BUYER:

THE ASHWILL TRUST,                SUPERGEN, INC.
ESTABLISHED NOVEMBER 8, 1989

BY:  /s/ Ellwin E. Ashwill        BY:  /s/ Hank Settle
   ------------------------------    --------------------------------------
    Ellwin E. Ashwill, Trustee              Hank Settle

DATE:  12-23-96                   DATE: Dec. 19, 1996
    -----------------------------      ------------------------------------

<PAGE>
                     PROPERTY INFORMATION SHEET
                          (Non-Residential)

          LEE & ASSOCIATES COMMERCIAL REAL ESTATE SERVICES

TO WHOM IT MAY CONCERN:

The Ashwill Trust ("Owner"), owns the property commonly known by the street
address of 1059 Serpentine Lane, located in the City of Pleasanton, County of
Alameda, State of California, and generally described as (describe briefly the
nature of the  property):
                         -------------------------------------------------------
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
("Property"), and certifies that:

    1. MATERIAL PHYSICAL DEFECTS.  Owner has no actual knowledge of any
material physical defects in the Property or any improvements and structures
thereon, including, but not limited to the roof, except (it will be assumed no
known exceptions exist unless they are specified here):
                                                       -----------------------
------------------------------------------------------------------------------
------------------------------------------------------------------------------
-----------------------------------------------------------------------------.

    2. EQUIPMENT.  Owner has no actual knowledge that the heating, ventilating,
air conditioning, plumbing, loading doors, electrical and lighting systems, life
safety systems and mechanical equipment existing on the Property as of the date
hereof, if any are not in good operating order and condition, except (it will be
assumed no known exceptions exist unless they are specified here):
                                                                  --------------
--------------------------------------------------------------------------------
-------------------------------------------------------------------------------.

    3. SOIL CONDITIONS.  Owner has no actual knowledge that the Property has
any slipping, sliding, settling, flooding, ponding, or any other grading,
drainage or soil problems, except (it will be assumed no known exceptions exist
unless they are specified here):
                               ------------------------------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

    4. SEWER.  Owner represents and warrants that the Property is served by a
(check appropriate box /x/ public sewer system or /  / private septic
system, and that, if the Property is served by a public sewer system, the
cost of installation of such sewer system has been fully paid, except (it
will be assumed no known exceptions exist unless they are specified here):
------------------------------------------------------------------------------
-----------------------------------------------------------------------------.

    5. EARTHQUAKE ZONE.  If the Property is located in the State of California,
Owner has no actual knowledge that the Property is located within a delineated
special studies zone (a zone that encompasses a potentially or recently active
trace of an earthquake fault that is deemed by the state geologist to be
sufficiently active and well defined enough to constitute a potential hazard to
structures from surface fault or fault creep) under an Alquist-Priolo Special
Studies Zone Map, except (it will be assumed that no known exceptions exist,
unless they are specified here):
                                -----------------------------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

<PAGE>

    6. COMPLIANCE WITH LAWS.  Owner has no actual knowledge of any aspect or
condition of the Property which violates applicable laws, rules, regulations,
codes or covenants, conditions, or restrictions, or of improvements or
alterations made to the Property without a permit where one was required, or of
any unfulfilled order or directive of any applicable government agency or of any
casualty insurance company that any work of investigation, remediation, repair,
maintenance or improvement is to be performed on the Property, except (it will
be assumed no known exceptions exist unless they are specified here):
                                                                     ----------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

    7. HAZARDOUS SUBSTANCES.  Owner has no actual knowledge of the current
existence on the Property of asbestos, PCB  transformers or any hazardous,
toxic, or infectious substance whose nature and/or quantity of existence, use,
manufacture, or effect, render it subject to Federal, state, or local
regulation, investigation, remediation or removal as potentially injurious to
public health or welfare, except (it will be assumed no known exceptions exist
unless they are specified here):
                                -----------------------------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

    8. STORAGE TANKS.  Owner has no actual knowledge of the past or present
existence of any above or below ground storage tank or tanks on the Property,
except (it will be assumed no known exceptions exist unless they are specified
here):
      -------------------------------------------------------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

    9. ACTION, SUITS OR PROCEEDINGS.  Owner has no actual knowledge that any
actions, suits or proceedings are pending or threatened before any court,
arbitration tribunal, governmental department, commission, board, bureau,
agency, or instrumentality that would affect the Property or the right or
ability of an Owner or Tenant to convey, occupy, or utilize the Property, except
(it will be assumed no known exceptions exist unless they are specified here):
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
-------------------------------------------------------------------------------.

    10. GOVERNMENTAL PROCEEDINGS.  Owner has no actual knowledge of any
existing or contemplated condemnation, environmental, zoning, redevelopment
agency plan or any other land use regulation proceedings which could
detrimentally affect the value, use and operation of the Property, except (it
will be assumed no known exceptions exist unless they are specified here):
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

    11. UNRECORDED TITLE MATTERS.  Owner has no actual knowledge of any
encumbrances, covenants, conditions, restriction, easements, licenses, liens,
charges or other matters which affect the title of the Property that are not
recorded in the official records of the county recorder where the Property is
located, except (it will be assumed no known exceptions exist unless they are
specified here):
                ---------------------------------------------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.
                                        -2-

<PAGE>

    12. LEASES.  Owner has no actual knowledge of any leases, subleases, or
other tenancy agreements affecting the Property, except (it will be assumed no
known exceptions exist unless they are specified here):
                                                       ------------------------
-------------------------------------------------------------------------------
------------------------------------------------------------------------------.

    Owner's statements herein will be relied upon by brokers, buyers, lessees,
lenders and others.  Therefore, Owner has reviewed and modified this printed
statement as necessary to accurately and completely state all the known
material facts concerning the Property.  To the extent such modifications are
not made, this statement may be relied upon as printed.  This statement,
however, shall not relieve a buyer or lessee of responsibility for independent
investigation of the Property.  Owner agrees to promptly notify, in writing,
all appropriate parties of any material changes which may occur in the
statements contained herein from the date this statement is signed until title
to the Property is transferred, by a recorded deed, by Owner.

                                            "OWNER"

Date: 12/23    1996                         The Ashwill Trust
    --------------------------------        ----------------------------------
    (fill in date of execution)

                                             By:  /s/ Ellwin E. Ashwill
                                                ------------------------------
                                             Name Printed:  Ellwin E. Ashwill
                                             Title:  Trustee

                                             By:
                                                ------------------------------
                                             Name Printed:
                                                          --------------------
                                             Title:
                                                   ---------------------------
                                        -3-

<PAGE>

                       UNIFORM DISCLAIMER FORM
                              SALE FORM

1.  LEGAL EFFECT.  Upon acceptance of the Purchase Contract and Deposit
    Receipt, or any counteroffer thereto, Seller and Buyer both intend to have
    a binding legal agreement for the purchase of the Premises on the terms and
    conditions set forth therein.  Seller and Buyer acknowledge that Broker is
    not qualified to practice law, nor authorized to give legal advice or
    counsel you as to any legal matters affecting this document.  Broker hereby
    advises Seller and Buyer to consult with their respective attorneys in
    connection with any questions each may have as to legal ramifications or
    effects of this document, prior to its execution.

2.  FORM OF PURCHASE CONTRACT AND DEPOSIT RECEIPT.  The proposed document is a
    standard form document, and Broker makes no representations or warranties
    with respect to the adequacy of this document for either Seller's or
    Buyer's particular purposes.  Broker has, at the direction of Seller and/or
    Buyer, "filled in the blanks" from information provided to Broker based on
    prior correspondence, discussions of the parties with respect to the
    Purchase Contract and Deposit Receipt, and subsequent counteroffers between
    the parties hereto.  By initialing this Paragraph, Seller and Buyer
    acknowledge and agree that the Purchase Contract and Deposit Receipt is
    delivered to each subject to the express condition that Broker has merely
    followed the instructions of the parties in preparing this document, and
    does not assume any responsibility for its accuracy, completeness or form.
    Seller and Buyer acknowledge and agree that in  providing this document,
    Broker has acted to expedite this transaction on behalf of Seller and
    Buyer, and has functioned within the scope of professional ethics by doing
    so.

              Seller's initials: /s/             Buyer's Initials: /s/
                                -----------                       -----------
3.  NO INDEPENDENT INVESTIGATION.  Seller and Buyer acknowledge and understand
    that any financial statements, information, reports, or written materials
    of any nature whatsoever, as provided by the parties to Broker, and
    thereafter submitted by Broker to either Seller and/or Buyer, are so
    provided without any independent investigation by Broker, and as such
    Broker assumes no responsibility or liability for the accuracy or validity
    of the same.  Any verification of such submitted documents is solely and
    completely the responsibility of the party to whom such documents have been
    submitted.

4.  NO WARRANTY.  Seller and Buyer acknowledge and agree that no warranties,
    recommendations, or representations are made by the broker as to the
    accuracy, the legal sufficiency, the legal effect of the tax consequences
    of any of the documents submitted by Broker to Seller and/or Buyer
    referenced in Paragraph 3 above, nor of the legal sufficiency, legal
    effect, or tax consequences of the transactions contemplated thereby.
    furthermore, Seller and Buyer acknowledge and agree that Broker has made no
    representations concerning the ability of the Buyer to use the Premises for
    their intended use, and Buyer is relying solely on its own investigation of
    the Premises in accepting the Purchase Contract and Deposit Receipt.

5.  NOTICE REGARDING HAZARDOUS WASTES OR SUBSTANCES AND UNDERGROUND STORAGE
    TANKS.  Although Broker will disclose any knowledge it actually possesses
    with respect to the existence of any hazardous wastes, substances, or
    underground storage tanks at the Premises, Broker has not made any
    independent investigations or obtained reports with respect thereto, except
    as may be described in a separate written document signed by Broker.  All
    parties hereto acknowledge and understand that Broker makes no
    representations regarding the existence or nonexistence of hazardous
    wastes, substances, or underground storage tanks at the Premises.  Each
    party should contact a professional, such as a civil engineer, geologist,
    industrial hygienist or other persons with experience in these matters to
    advise you concerning the property.

<PAGE>

6.  DISCLOSURE RESPECTING AMERICANS WITH DISABILITIES ACT.  The United States
    Congress has recently enacted the Americans With Disabilities Act.  Among
    other things, this act is intended to make many business establishments
    equally accessible to persons with a variety of disabilities; modifications
    to real property may be required.  State and local laws also may mandate
    changes.  Broker is not qualified to advise you as to what, if any, changes
    may be required now or in the future.  Broker recommends that you consult
    the attorneys and qualified design professionals of your choice for
    information regarding these matters.

7.  ATTORNEYS' FEES.  In any action, proceeding or arbitration arising out of
    this Agreement, the prevailing party shall be entitled to reasonable
    attorneys' fees and costs.

8.  ENTIRE AGREEMENT.  This document constitutes the entire agreement between
    parties with respect to the subject matter contained herein and supersedes
    all prior or contemporaneous agreements, representations, negotiations and
    understandings of the parties, other than such writings as may be executed
    and/or delivered by the parties pursuant hereto.  There are no oral
    agreements or implied covenants by the Seller or Buyer, or by their
    respective employees, or other representatives.


    Date:   12-23-96                        Date:  Dec. 19, 1996
         ---------------------------             --------------------------
    Seller: /s/ Ellwin E. Ashwill           Buyer: Hank Settle
          --------------------------             --------------------------
         Ellwin E. Ashwill,
         The Ashwill Trust


                                        -2-

<PAGE>

                                     Exhibit A

                                     SITE PLAN
                                  CONDOMINIUM PLAN
                                        FOR
                                  PARCEL MAP 7030
                           CITY OF PLEASANTON CALIFORNIA





<PAGE>


                                     Exhibit B

                                    BUILDING "B"
                                   BUILDING PLAN

                                  CONDOMINIUM PLAN
                                        FOR
                                  PARCEL MAP 7030
                           CITY OF PLEASANTON CALIFORNIA


<PAGE>


Ashwill Trust
c/o Robert S. Kumnick
Lee & Associates
5960 Stoneridge Drive
Suite 101
Pleasanton, CA 94588

RE:   SUPERGEN, INC. - BUILDING PURCHASE
      1059 SERPENTINE LANE, PLEASANTON, CALIFORNIA

Dear Gene:

Per Addendum A of the Purchase Contract, this letter will serve as
notification that all contract contingencies for financing (loan) have been
approved and waived by SuperGen, Inc.




Approved:  /s/ Joseph Rubinfeld                                       2/21/97
         --------------------------------------------------------------------
               Joseph Rubinfeld, President / CEO                         Date

Approved:  /s/ Henry C. Settle, Jr.                          February 21, 1997
         ---------------------------------------------------------------------
          Henry C. Settle, Jr., Chief Financial Officer, SuperGen, Inc.   Date