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                                                                    Exhibit 4.19


                               BIOPURE CORPORATION

                                     WARRANT


Warrant No. BW -                                         Dated: January __, 2006

     Biopure Corporation, a Delaware corporation (the "COMPANY"), hereby
certifies that, for value received, _______. or its registered assigns
(including permitted transferees, the "HOLDER"), is entitled to purchase from
the Company up to a total of ______ shares (as adjusted from time to time as
provided in SECTION 9) of Common Stock (as defined below), together with the
associated preferred stock purchase rights under that certain Rights Agreement
(the "RIGHTS AGREEMENT") dated as of as of September 24, 1999 between the
Company and American Stock Transfer & Trust Company, as rights agent, to the
extent the Rights Agreement is in effect on the date of such purchase, at an
exercise price equal to $1.03 per share (as adjusted from time to time as
provided in SECTION 9, the "EXERCISE PRICE"), at any time and from time to time
from and after January 17, 2006 (the "INITIAL EXERCISE DATE") to and including
January 17, 2011 (the "EXPIRATION DATE"), and subject to the following terms and
conditions.

     1. DEFINITIONS. The capitalized terms used herein and not otherwise defined
shall have the meanings set forth below:

          "AFFILIATE" of any specified Person means any other person or entity
directly or indirectly controlling, controlled by or under direct or indirect
common control with such specified Person. For purposes of this definition,
"CONTROL" means the power to direct the management and policies of such Person
or firm, directly or indirectly, whether through the ownership of voting
securities, by contract or otherwise.

          "COMMISSION" means the United States Securities and Exchange
Commission.

          "COMMON STOCK" means the Class A common stock of the Company, $0.01
par value per share.

          "ELIGIBLE MARKET" means any of the New York Stock Exchange, the
American Stock Exchange or Nasdaq, and any successor markets thereto.

          "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended

          "MARKET PRICE" shall mean (i) if the principal trading market for such
securities is an exchange, the average of the last reported sale prices per
share for the last ten previous Trading Days in which a sale was reported, as
officially reported on any consolidated tape, (ii) if clause (i) is not
applicable, the average of the closing bid price per share for the last ten
previous Trading Days as set forth by Nasdaq or (iii) if clauses (i) and (ii)
are not applicable, the average of the closing bid price per share for the last
ten previous Trading Days as set forth in the National Quotation Bureau sheet
listing for such securities. Notwithstanding the foregoing, if there is no
reported sales price or closing bid price, as the case may be, on any of the ten
Trading Days preceding the event requiring a determination of Market Price
hereunder, then the Market Price shall be determined in good faith after
reasonable investigation by resolution of the Board of Directors of the Company.

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          "NASDAQ" means the Nasdaq Capital Market or Nasdaq National Market,
and any successor markets thereto.

          "OTHER SECURITIES" refers to any capital stock (other than Common
Stock) and other securities of the Company or any other Person which the Holder
of this Warrant at any time shall be entitled to receive, or shall have
received, pursuant to the terms hereof upon the exercise of this Warrant, in
lieu of or in addition to Common Stock.

          "PERSON" means any court or other federal, state, local or other
governmental authority or other individual or corporation, partnership, trust,
incorporated or unincorporated association, joint venture, limited liability
company, joint stock company, government (or an agency or subdivision thereof)
or other entity of any kind.

          "REGISTRATION STATEMENT" means the Company's Registration Statement
(File Nos. 333-114559), as such registration statements are amended,
supplemented or replaced.

          "TRADING DAY" means (a) any day on which the Common Stock is listed or
quoted and traded on any Eligible Market or (b) if the Common Stock is not then
quoted and traded on any Eligible Market, then a day on which trading occurs on
the Nasdaq National Market (or any successor thereto).

          "WARRANT SHARES" shall initially mean shares of Common Stock (together
with the associated preferred stock purchase rights under the Rights Agreement
to the extent the Rights Agreement is in effect on the applicable date) and in
addition may include Other Securities and Substituted Property (as defined in
SECTION 9(e)(x)) issued or issuable from time to time upon exercise of this
Warrant.

     2. REGISTRATION OF WARRANT. The Company shall register this Warrant, upon
records to be maintained by the Company for that purpose (the "WARRANT
REGISTER"), in the name of the record Holder hereof from time to time. The
Company may deem and treat the registered Holder of this Warrant as the absolute
owner hereof for the purpose of any exercise hereof or any distribution to the
Holder, and for all other purposes.

     3. REGISTRATION OF TRANSFERS. The Company shall register the transfer of
any portion of this Warrant in the Warrant Register, upon surrender of this
Warrant, with the Form of Assignment attached hereto as Appendix A duly
completed and signed, to the Company at its address specified herein. Upon any
such registration and transfer, a new warrant in substantially the form of a
Warrant (any such new warrant, a "NEW WARRANT"), evidencing the portion of this
Warrant so transferred shall be issued to the transferee and a New Warrant
evidencing the remaining portion of this Warrant not so transferred, if any,
shall be issued to the transferring Holder. The acceptance of the New Warrant by
the transferee thereof shall be deemed the acceptance by such transferee of all
of the rights and obligations of a holder of a Warrant.

     4. EXERCISE AND DURATION OF WARRANT.

        (a) This Warrant shall be exercisable, either in its entirety or for a
portion of the number of Warrant Shares, by the registered Holder at any time
and from time to time from and after the Initial Exercise Date to and including
the Expiration Date. At 5:00 P.M. New York City

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time on the Expiration Date, the portion of this Warrant not exercised prior
thereto shall be and become void and of no value, and the Holder hereof shall
have no right to purchase any additional Warrant Shares hereunder.

        (b) A Holder may exercise this Warrant by delivering to the Company, in
accordance with Section 13, this Warrant, together with (i) an exercise notice,
in the form attached hereto as APPENDIX B (the "EXERCISE NOTICE"), appropriately
completed and duly signed, and (ii) payment of the Exercise Price for the number
of Warrant Shares as to which this Warrant is being exercised (as set forth in
SECTION 4(c) below), and the date such items are received by the Company is an
"EXERCISE DATE." Execution and delivery of an Exercise Notice in respect of less
than all of the Warrant Shares issuable upon exercise of this Warrant shall
result in the cancellation of the original Warrant and issuance of a New Warrant
evidencing the right to purchase the remaining number of Warrant Shares.

        (c) The Holder shall pay the Exercise Price in cash, by certified bank
check payable to the order of the Company or by wire transfer of immediately
available funds in accordance with the Company's instructions.

        (d) Except as otherwise provided for herein, this Warrant shall not
entitle the Holder to any voting rights or other rights as a stockholder of the
Company by virtue of the ownership hereof.

        (e) Notwithstanding anything to the contrary herein, after the sixth
(6th) month anniversary of the date hereof, the Company may, by written notice
to the Holder, require that the Holder execute and deliver to the Company an
Exercise Notice exercising all of the Warrant Shares then held by such Holder
within twenty Business Days of the date of the Company's notice; provided,
however, that the Company may only provide such notice if the daily volume
weighted average price per share of the Common Stock for each of the ten
consecutive trading days ended immediately prior to the Company's notice is
equal to or greater than the Exercise Price multiplied by 1.5. At 5:00 P.M. New
York City time on such 20th Business Day, the portion of this Warrant not
exercised prior thereto shall be and become void and of no value, and the Holder
hereof shall have no right to purchase any additional Warrant Shares hereunder.

     5. DELIVERY OF WARRANT SHARES.

        (a) Upon exercise of this Warrant, the Company shall promptly issue or
cause to be issued and deliver or cause to be delivered to the Holder, in such
name or names as the Holder may designate, a certificate for the Warrant Shares
issuable upon such exercise (the "CERTIFICATE") bearing no restrictive legends.
The Holder, or any Person so designated by the Holder to receive the Warrant
Shares, shall be deemed to have become holder of record of such Warrant Shares
as of the Exercise Date.

        (b) The Warrant and the Warrant Shares will be registered pursuant to
the Registration Statement, and the Company covenants and agrees to maintain the
effectiveness of the Registration Statement until the Expiration Date.
Notwithstanding the foregoing, in the event that, prior to the Expiration Date,
the Company ceases to be eligible under the Securities Act of 1933, as amended
(the "ACT") or the rules and regulations promulgated thereunder, to maintain a
registration statement on Form S-3, or in the event that the Warrant or the
Warrant Shares cease to be eligible for inclusion in such Registration Statement
to the extent necessary to permit the Holder to exercise the Warrant and sell
the Warrant Shares without restriction under the Act, the

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Company will promptly (and in any event within 10 days of the date that the
Warrant or any Warrant Shares cease to be so eligible), amend or file a new
registration statement under the Act on a form eligible for use by the Company
for the registration of such securities and use its best efforts to have such
registration statement declared effective by the Commission as soon as
practicable after such filing, which registration statement shall include such
information as may be required to permit the exercise of the Warrant and the
sale of the Warrant Shares without restriction under the Act. The Holder
acknowledges and agrees that the Warrant shall be exercisable pursuant to any
such registration statement only at such times as the registration statement is
effective or in accordance with any applicable exemption from the registration
requirements of the Act. Upon such Registration Statement's being declared
effective by the Commission, the Company shall use its best efforts to cause the
Registration Statement to remain effective for a period of at least six (6)
consecutive months from the date that the Holders of the Warrants and Warrant
Shares covered by such Registration Statement are first given the opportunity to
sell all of such securities. In the event that ninety (90) days prior to the
Expiration Date, the Registration Statement registering the Warrant Shares is
not effective or is withdrawn or the Commission issues a stop order suspending
the effectiveness of such Registration Statement, the Company hereby agrees to
extend the Expiration Date for (x) an additional ninety (90) days or (y) until
the Registration Statement is declared effective by the SEC, whichever period is
longer. During such time as the Warrant Shares are registered pursuant to any
registration statement under the Act, the Company further covenants and agrees
to make timely filings of all documents required to be filed under the Act or
the Exchange Act in order to ensure that the registration statement, including
the documents incorporated by reference therein, if any, do not contain an
untrue statement of a material fact or omit to state any material fact required
to be stated therein or necessary in order to make the statements therein not
misleading.

        (c) This Warrant is exercisable, either in its entirety or, from time to
time, for a portion of the number of Warrant Shares. Upon surrender of this
Warrant following one or more partial exercises, the Company shall issue or
cause to be issued, at its expense, a New Warrant evidencing the right to
purchase the remaining number of Warrant Shares.

     6. CHARGES, TAXES AND EXPENSES. Issuance and delivery of certificates for
shares of Common Stock upon exercise of this Warrant shall be made without
charge to the Holder for any issue or transfer tax, withholding tax, transfer
agent fee or other incidental tax or expense in respect of the issuance of such
certificates, all of which taxes and expenses shall be paid by the Company;
provided, however, that the Company shall not be required to pay any tax which
may be payable in respect of any transfer involved in the issue, delivery or
registration of any certificates for Warrant Shares or Warrant in a name other
than that of the Holder and that the Holder will be required to pay any tax with
respect to cash received in lieu of fractional shares. The Holder shall be
responsible for all other tax liability that may arise as a result of holding or
transferring this Warrant or receiving Warrant Shares upon exercise hereof.

     7. REPLACEMENT OF WARRANT. If this Warrant is mutilated, lost, stolen or
destroyed, the Company, at the sole expense of the Holder (such expenses, if any
imposed by the Company to be reasonable), shall issue or cause to be issued in
exchange and substitution for and upon cancellation hereof, or in lieu of and in
substitution for this Warrant, a New Warrant, but only upon receipt of evidence
reasonably satisfactory to the Company of such loss, theft or destruction and
customary and reasonable indemnity, if requested by the Company.

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     8. RESERVATION OF WARRANT SHARES. The Company covenants that it will at all
times reserve and keep available out of the aggregate of its authorized but
unissued and otherwise unreserved Common Stock, solely for the purpose of
enabling it to issue Warrant Shares upon exercise of this Warrant as herein
provided, the number of Warrant Shares which are then issuable and deliverable
upon the exercise of this entire Warrant, free from all taxes, liens, claims,
encumbrances with respect to the issuance of such Warrant Shares and will not be
subject to any pre-emptive rights or similar rights (taking into account the
adjustments and restrictions of Section 9 hereof). The Company covenants that
all Warrant Shares so issuable and deliverable shall, upon issuance and the
payment of the applicable Exercise Price in accordance with the terms hereof, be
duly and validly authorized, issued, fully paid and nonassessable. The Company
will take all such action as may be necessary to assure that such shares of
Common Stock may be issued as provided herein without violation of any
applicable law or regulation, or of any requirements of any securities exchange
or automated quotation system upon which the Common Stock may be listed or
quoted, as the case may be; provided, however, that such actions shall only
require the Company's best efforts (or other specified standard) to the extent
specifically provided for in this Warrant.

     9. CERTAIN ADJUSTMENTS. The Exercise Price and number of Warrant Shares
issuable upon exercise of this Warrant are subject to adjustment from time to
time as set forth in this Section 9.

        (a) Stock Dividends. If the Company, at any time while this Warrant is
outstanding, pays a dividend on its Common Stock payable in additional shares of
Common Stock or otherwise makes a distribution on any class of capital stock
that is payable in shares of Common Stock, then in each such case the Exercise
Price shall be multiplied by a fraction, (A) the numerator of which shall be the
number of shares of Common Stock outstanding immediately prior to the opening of
business on the day after the record date for the determination of stockholders
entitled to receive such dividend or distribution and (B) the denominator of
which shall be the number of shares of Common Stock outstanding immediately
after the distribution date of such dividend or distribution. Any adjustment
made pursuant to this SECTION 9(a) shall become effective immediately after the
record date for the determination of stockholders entitled to receive such
dividend or distribution; PROVIDED, HOWEVER, that if following such record date
the Company rescinds or modifies such dividend or distribution, the Exercise
Price shall be appropriately adjusted (as of the date that the Company
effectively rescinds or modifies such dividend or distribution) to take into
account the effect of such rescinded or modified dividend or distribution on the
Exercise Price pursuant to this Section 9(a).

        (b) Stock Splits. If the Company, at any time while this Warrant is
outstanding, (i) subdivides outstanding shares of Common Stock into a larger
number of shares, or (ii) combines outstanding shares of Common Stock into a
smaller number of shares, then in each such case the Exercise Price shall be
multiplied by a fraction, (A) the numerator of which shall be the number of
shares of Common Stock outstanding immediately before such event and (B) the
denominator of which shall be the number of shares of Common Stock outstanding
immediately after such event. Any adjustment pursuant to this SECTION 9(b) shall
become effective immediately after the effective date of such subdivision or
combination.

        (c) Reclassifications. A reclassification of the Common Stock (other
than any such reclassification in connection with a merger or consolidation to
which SECTION 9(e) applies) into shares of any other class of stock shall be
deemed:

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          (i) a distribution by the Company to the holders of its Common Stock
of such shares of such other class of stock for the purposes and within the
meaning of this SECTION 9; and

          (ii) if the outstanding shares of Common Stock shall be changed into a
larger or smaller number of shares of Common Stock as part of such
reclassification, such change shall be deemed a subdivision or combination, as
the case may be, of the outstanding shares of Common Stock for the purposes and
within the meaning of SECTION 9(b).

        (d) Other Distributions. If the Company, at any time while this Warrant
is outstanding, distributes to holders of Common Stock (i) evidences of its
indebtedness, (ii) shares of any class of capital stock, (iii) rights or
warrants to subscribe for or purchase any shares of any class of capital stock
or (iv) any other asset, other than a distribution of Common Stock covered by
SECTION 9(a), (in each case, "DISTRIBUTED PROPERTY"), then in each such case the
Exercise Price in effect immediately prior to the record date fixed for
determination of stockholders entitled to receive such distribution (and the
Exercise Price thereafter applicable) shall be adjusted (effective on and after
such record date) to equal the product of such Exercise Price multiplied by a
fraction, (A) the numerator of which shall be Market Price on such record date
less the then fair market value of the Distributed Property distributed in
respect of one outstanding share of Common Stock, which, if the Distributed
Property is other than cash or marketable securities, shall be as determined in
good faith by the Board of Directors of the Company whose determination shall be
described in a board resolution, and (B) the denominator of which shall be the
Market Price on such record date; PROVIDED, HOWEVER, that if following the
record date for such distribution the Company rescinds or modifies such
distribution, the Exercise Price shall be appropriately adjusted (as of the date
that the Company effectively rescinds or modifies such distribution) to take
into account the effect of such rescinded or modified distribution on the
Exercise Price pursuant to this Section 9(d).

        (e) Fundamental Transactions. If, at any time following the Initial
Exercise Date, (i) the Company effects any merger or consolidation of the
Company with or into another Person, (ii) the Company effects any sale of all or
substantially all of its assets in one or a series of related transactions or
(iii) there shall occur any merger of another Person into the Company whereby
the Common Stock is cancelled, converted or reclassified into or exchanged for
other securities, cash or property (in any such case, a "FUNDAMENTAL
TRANSACTION"), then, as a condition to the consummation of such Fundamental
Transaction, the Company shall (or, in the case of any Fundamental Transaction
in which the Company is not the surviving entity, the Company shall take all
reasonable steps to cause such other Person to) execute and deliver to the
Holder of this Warrant a written instrument providing that:

          (x) so long as this Warrant remains outstanding, upon the exercise
hereof at any time on or after the consummation of such Fundamental Transaction
and on such terms and subject to such conditions as shall be nearly equivalent
as may be practicable to the provisions set forth in this Warrant, this Warrant
shall be exercisable into, in lieu of Common Stock issuable upon such exercise
prior to such consummation, the securities or other property (the "SUBSTITUTED
PROPERTY") that would have been received in connection with such Fundamental
Transaction by a holder of the number of shares of Common Stock into which this
Warrant was exercisable immediately prior to such Fundamental Transaction,
assuming such holder of Common Stock:

               (A) is not a Person with which the Company consolidated or into
which the Company merged or which merged into the Company or to which such sale
or transfer was made, as the case may be (a "CONSTITUENT PERSON"), or an
Affiliate of a Constituent Person; and

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               (B) failed to exercise such Holder's rights of election, if any,
as to the kind or amount of securities, cash and other property receivable in
connection with such Fundamental Transaction (provided, however, that if the
kind or amount of securities, cash or other property receivable in connection
with such Fundamental Transaction is not the same for each share of Common Stock
held immediately prior to such Fundamental Transaction by a Person other than a
Constituent Person or an Affiliate thereof and in respect of which such rights
of election shall not have been exercised (a "NON-ELECTING SHARE"), then, for
the purposes of this SECTION 9(e), the kind and amount of securities, cash and
other property receivable in connection with such Fundamental Transaction by
each Non-Electing Share shall be deemed to be the kind and amount so receivable
per share by a plurality of the Non-Electing Shares); and

          (y) the rights and obligations of the Company (or, in the event of a
transaction in which the Company is not the surviving Person, such other Person)
and the Holder in respect of Substituted Property shall be as nearly equivalent
as may be practicable to the rights and obligations of the Company and Holder in
respect of Common Stock hereunder.

        Such written instrument shall provide for adjustments which, for events
subsequent to the effective date of such written instrument, shall be as nearly
equivalent as may be practicable to the adjustments provided for in this SECTION
9. The above provisions of this SECTION 9(e) shall similarly apply to successive
Fundamental Transactions.

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        (f) Adjustment of Warrant Shares. Simultaneously with any adjustment to
the Exercise Price pursuant to paragraphs (a) through (d) of this SECTION 9, the
number of Warrant Shares that may be purchased upon exercise of this Warrant
shall be increased or decreased proportionately, so that after such adjustment
the aggregate Exercise Price payable hereunder for the increased or decreased
number of Warrant Shares shall be the same as the aggregate Exercise Price
payable for the Warrant Shares immediately prior to such adjustment.

        (g) Calculations. All calculations under this SECTION 9 shall be made to
the nearest cent or the nearest 1/100th of a share, as applicable. The number of
shares of Common Stock outstanding at any given time shall not include shares
owned or held by or for the account of the Company, and the disposition of any
such shares shall be considered an issue or sale of Common Stock.

        (h) Adjustments. Notwithstanding any provision of this SECTION 9, no
adjustment of the Exercise Price shall be required if such adjustment is less
than $0.01; provided, however, that any adjustments which by reason of this
SECTION 9(h) are not required to be made shall be carried forward and taken into
account for purposes of any subsequent adjustment required to be made hereunder.

        (i) Notice of Adjustments. Upon the occurrence of each adjustment
pursuant to this SECTION 9, the Company will promptly deliver to the Holder a
certificate executed by the Company's Chief Financial Officer setting forth, in
reasonable detail, the event requiring such adjustment and the method by which
such adjustment was calculated, the adjusted Exercise Price and the adjusted
number or type of Warrant Shares or other securities issuable upon exercise of
this Warrant (as applicable). The Company will retain at its office copies of
all such certificates and cause the same to be available for inspection at said
office during normal business hours by the Holder or any prospective purchaser
of the Warrant designated by the Holder.

        (j) Notice of Corporate Events. If the Company (i) declares a dividend
or any other distribution of cash, securities or other property in respect of
its Common Stock, including, without limitation, any granting of rights or
warrants to subscribe for or purchase any capital stock of the Company or any
subsidiary of the Company, (ii) authorizes, approves, enters into any agreement
contemplating, or solicits stockholder approval for, any Fundamental Transaction
or (iii) authorizes the voluntary dissolution, liquidation or winding up of the
affairs of the Company, then the Company shall deliver to the Holder a notice
describing the material terms and conditions of such transaction at least 15
calendar days prior to the applicable record or effective date on which a Person
would need to hold Common Stock in order to participate in or vote with respect
to such transaction, and the Company will take all steps reasonably necessary in
order to ensure that the Holder is given the practical opportunity to exercise
this Warrant prior to such time so as to participate in or vote with respect to
such transaction; provided, however, that the failure to deliver such notice or
any defect therein shall not affect the validity of the corporate action
required to be described in such notice.

     10. FRACTIONAL SHARES. The Company shall not be required to issue or cause
to be issued fractional Warrant Shares on the exercise of this Warrant. If any
fraction of a Warrant Share would, except for the provisions of this Section 10,
be issuable upon exercise of this Warrant, the Company shall make a cash payment
to the Holder equal to (a) such fraction multiplied by (b) the Market Price on
the Exercise Date of one full Warrant Share.

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     11. LISTING ON SECURITIES EXCHANGES. The Company has listed, and will use
its best efforts to maintain the listing of, the Warrant Shares on Nasdaq. In
furtherance and not in limitation of any other provision of this Warrant, if the
Company at any time shall list any Common Stock on any Eligible Market other
than Nasdaq, the Company will, at its expense, simultaneously list the Warrant
Shares (and use its best efforts to maintain such listing) on such Eligible
Market, upon official notice of issuance following the exercise of this Warrant;
and the Company will so list, register and use its best efforts to maintain such
listing on any Eligible Market any Other Securities, if and at the time that any
securities of like class or similar type shall be listed on such Eligible Market
by the Company.

     12. REMEDIES. The Company stipulates that the remedies at law of the Holder
of this Warrant in the event of any default or threatened default by the Company
in the performance of or compliance with any of the terms of this Warrant are
not and will not be adequate, and that such terms may be specifically enforced
by a decree for the specific performance of any agreement contained herein or by
an injunction against a violation of any of the terms hereof or otherwise.

     13. NOTICES. Any and all notices or other communications or deliveries
hereunder (including without limitation any Exercise Notice) shall be in writing
and shall be mailed by certified mail, return receipt requested, or by a
nationally recognized courier service or delivered (in person or by facsimile),
against receipt to the party to whom such notice or other communication is to be
given. Any notice or other communication given by means permitted by this
Section 13 shall be deemed given at the time of receipt thereof. The address for
such notices or communications shall be as set forth below:

     If to the Company:       Biopure Corporation
                              11 Hurley Street
                              Cambridge, MA 02141

     If to the Holder:        c/o Biopure Corporation
                              11 Hurley Street
                              Cambridge, MA 02141

Or such other address as is provided to such other party in accordance with this
Section 13.

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     14. WARRANT AGENT. The Company shall serve as warrant agent under this
Warrant. Upon a prompt written notice to the Holder, the Company may appoint a
new warrant agent. Any Person into which any new warrant agent may be merged,
any Person resulting from any consolidation to which any new warrant agent shall
be a party or any Person to which any new warrant agent transfers substantially
all of its corporate trust or shareholders services business shall be a
successor warrant agent under this Warrant without any further act. Any such
successor warrant agent shall promptly cause notice of its succession as warrant
agent to be mailed (by first class mail, postage prepaid) to the Holder at the
Holder's last address as shown on the Warrant Register.

     15. MISCELLANEOUS. (a) This Warrant may be assigned by the Holder. This
Warrant may not be assigned by the Company, except to a successor in the event
of a Fundamental Transaction. This Warrant shall be binding on and inure to the
benefit of the parties hereto and their respective successors and assigns.
Subject to the preceding sentence, nothing in this Warrant shall be construed to
give to any Person other than the Company and the Holder any legal or equitable
right, remedy or cause of action under this Warrant. This Warrant may be amended
only in writing signed by the Company and the Holder and their successors and
assigns.

        (b) The Company will not, by amendment of its governing documents or
through any reorganization, transfer of assets, consolidation, merger,
dissolution, issue or sale of securities or any other voluntary action, avoid or
seek to avoid the observance or performance of any of the terms of this Warrant,
but will at all times in good faith assist in the carrying out of all such terms
and in the taking of all such action as may be necessary or appropriate in order
to protect the rights of the Holder against impairment. Without limiting the
generality of the foregoing, the Company (i) will not increase the par value of
any Warrant Shares above the amount payable therefor upon exercise thereof, and
(ii) will take all such action as may be reasonably necessary or appropriate in
order that the Company may validly and legally issue fully paid and
nonassessable Warrant Shares on the exercise of this Warrant, free from all
taxes, liens, claims and encumbrances and (iii) will not close its shareholder
books or records in any manner which interferes with the timely exercise of this
Warrant.

        (c) This Warrant shall be governed by and construed and enforced in
accordance with the laws of the State of New York. Each party hereby irrevocably
submits to the exclusive jurisdiction of the state and Federal courts sitting in
the City of New York, Borough of Manhattan, for the adjudication of any dispute
hereunder or in connection herewith or with any transaction contemplated hereby
or discussed herein, and hereby irrevocably waives, and agrees not to assert in
any suit, action or proceeding that it is not personally subject to the
jurisdiction of any such court or that such suit, action or proceeding is
improper. Each party hereby irrevocably waives personal service of process and
consents to process being served in any such suit, action or proceeding by
mailing a copy thereof via registered or certified mail or overnight delivery
(with evidence of delivery) to such party at the address in effect for notices
to it under this Warrant and agrees that such service shall constitute good and
sufficient service of process and notice thereof. Nothing contained herein shall
be deemed to limit in any way any right to serve process in any manner permitted
by law. THE PARTIES HEREBY WAIVE ALL RIGHTS TO A TRIAL BY JURY.

        (d) Neither party shall be deemed in default of any provision of this
Warrant, to the extent that performance of its obligations or attempts to cure a
breach hereof are delayed or prevented by any event reasonably beyond the
control of such party, including, without

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limitation, war, hostilities, acts of terrorism, revolution, riot, civil
commotion, national emergency, strike, lockout, unavailability of supplies,
epidemic, fire, flood, earthquake, force of nature, explosion, embargo, or any
other Act of God, or any law, proclamation, regulation, ordinance, or other act
or order of any court, government or governmental agency, provided that such
party gives the other party written notice thereof promptly upon discovery
thereof and uses reasonable efforts to cure or mitigate the delay or failure to
perform.

        (e) The headings herein are for convenience only, do not constitute a
part of this Warrant and shall not be deemed to limit or affect any of the
provisions hereof.

        (f) In case any one or more of the provisions of this Warrant shall be
deemed invalid or unenforceable in any respect, the validity and enforceability
of the remaining terms and provisions of this Warrant shall not in any way be
affected or impaired thereby and the parties will attempt in good faith to agree
upon a valid and enforceable provision which shall be a commercially reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Warrant.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK,
                             SIGNATURE PAGE FOLLOWS]

<PAGE>

     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed
by its authorized officer as of the date first indicated above.


                                     BIOPURE CORPORATION


                                     By:
                                        ---------------------------------
                                        Name:
                                        Title:

<PAGE>

                                   APPENDIX A
                                   ----------

                               FORM OF ASSIGNMENT

           (to be completed and signed only upon transfer of Warrant)

     FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto ____________________ the right represented by the within Warrant to
purchase _____________ shares of Common Stock of Biopure Corporation to which
the within warrant relates and appoints __________________________ attorney to
transfer said right on the books of Biopure Corporation with full power of
substitution in the premises.


Dated:____________                    ------------------------------------------
                                      (Signature must conform in all respects to
                                      name of Holder as specified on face of the
                                      Warrant)

                                      Address of Transferee:

                                      --------------------------------------

                                      --------------------------------------

                                      --------------------------------------

In the presence of:


----------------------------

<PAGE>

                                   APPENDIX B
                                   ----------

                             FORM OF EXERCISE NOTICE

(To be executed by the Holder to exercise the right to purchase shares of Common
Stock under the foregoing Warrant)

To:  Biopure Corporation

The undersigned is the Holder of Warrant No. [     ] (the "Warrant") issued by
Biopure Corporation, a Delaware corporation (the "Company"). Capitalized terms
used herein and not otherwise defined have the respective meanings set forth in
the Warrant.

1.   The Warrant is currently exercisable to purchase a total of _________
     Warrant Shares.

2.   The undersigned Holder hereby exercises its right to purchase _________
     Warrant Shares pursuant to the Warrant.

3.   The Holder shall pay the sum of $________ to the Company in accordance with
     the terms of the Warrant.

4.   Pursuant to this exercise, the Company shall deliver to the Holder Warrant
     Shares in accordance with the terms of the Warrant

5.   Following this exercise, the Warrant shall be exercisable to purchase a
     total of __________ Warrant Shares.


Dated: ____________                 Name of Holder:


                                    (Print)
                                           -------------------------------------

                                    By:
                                       -----------------------------------------

                                    Title:
                                          --------------------------------------

                                    (Signature must conform in all respects to
                                    name of Holder as specified on face of the
                                    Warrant)