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                                                                     Exhibit 4.2

          THIS WARRANT AND THE SHARES OF COMMON STOCK THAT ARE
          ISSUABLE UPON EXERCISE OF THE WARRANT MAY NOT BE SOLD,
          OFFERED FOR SALE, PLEDGED OR OTHERWISE TRANSFERRED UNLESS
          SUCH TRANSFER IS REGISTERED OR QUALIFIED UNDER THE
          SECURITIES ACT OF 1933, AS AMENDED, AND APPLICABLE STATE
          SECURITIES LAWS OR UNLESS THE COMPANY RECEIVES AN OPINION OF
          COUNSEL OR OTHER EVIDENCE REASONABLY SATISFACTORY TO IT TO
          THE EFFECT THAT SUCH REGISTRATION AND QUALIFICATION ARE NOT
          REQUIRED.

          WARRANT TO PURCHASE [      ] SHARES OF CLASS A COMMON STOCK
             (INCLUDING ASSOCIATED PREFERRED STOCK PURCHASE RIGHTS)

                            PLACEMENT AGENT'S WARRANT

                                Dated: [       ]

         This certifies that [      ] or its permitted transferee (sometimes
herein called the "Holder") is entitled to purchase from BIOPURE CORPORATION, a
Delaware corporation (the "Company"), at the price and during the period as
hereinafter specified, [      ] shares, including 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 (such shares collectively with such
associated rights, the "Shares") of Class A common stock, $0.01 par value per
share, of the Company (the "Common Stock") at a purchase price of [      ] per
share, subject to adjustment as described below (as so adjusted from time to
time, the "Exercise Price"), at any time during the five (5) year period
commencing on [      ] (the "Issue Date").

         1. The rights represented by this Warrant shall be exercisable at the
Exercise Price, and during the periods as follows:

                  (a) At any time and from time to time between the Issue Date
and the fifth anniversary of the Issue Date (the "Expiration Date") inclusive,
the Holder shall have the right to purchase Shares hereunder at the Exercise
Price.

                  (b) After the Expiration Date, the Holder shall have no right
to purchase all or any portion of the Shares hereunder.

         2. (a) The rights represented by this Warrant may be exercised at any
time within the period above specified, in whole or in part, by (i) the
surrender of this Warrant (with the purchase form at the end hereof properly
executed) at the principal executive office of the Company (or such other office
or agency of the Company as it may designate by notice in writing to the Holder
at the address of the Holder appearing on the books of the Company); (ii)
payment to the Company of the Exercise Price then in effect for the number of
Shares specified in the above-mentioned purchase form together with applicable
stock transfer taxes, if any; and

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(iii) delivery to the Company of a duly executed agreement signed by the
person(s) designated in the purchase form to the effect that such person(s)
agree(s) to be bound by the provisions of Section 6 and subsections (b), (c) and
(d) of Section 7 hereof. This Warrant shall be deemed to have been exercised, in
whole or in part to the extent specified, immediately prior to the close of
business on the date this Warrant is surrendered and payment is made in
accordance with the foregoing provisions of this Section 2, and the person or
persons in whose name or names the certificates for the Shares shall be issuable
upon such exercise shall become the holder or holders of record of such Shares
at that time and date. The Shares and the certificates for the Shares so
purchased shall be delivered to the Holder within a reasonable time, not
exceeding ten (10) business days, after the rights represented by this Warrant
shall have been so exercised.

                  (b) Notwithstanding anything to the contrary contained in
Section 2(a), the Holder may elect to exercise this Warrant in whole or in part
on a "cashless exercise basis" by receiving Shares equal to the value (as
determined below) of this Warrant, or any part hereof, upon surrender of this
Warrant at the principal office of the Company together with notice of such
election in which event the Company shall issue to the Holder a number of Shares
computed using the following formula:

                                   X =(Y(A-B))/A

         Where         X = the number of Shares to be issued to the Holder;

                       Y = the number of Shares issuable upon exercise of this
                           Placement Agent's Warrant;

                       A = the current fair market value of one share of
                           Common Stock (determined in the same manner as the
                           "current market price per share of Common Stock" is
                           to be determined pursuant to Section 8(e) of this
                           Warrant);

                       B = the Exercise Price.

         3. (a) Any transfer of this Warrant shall be effected by the Holder by
(i) executing the form of assignment at the end hereof and (ii) surrendering
this Warrant for cancellation at the office or agency of the Company referred to
in Section 2 hereof, accompanied by (x) a written instrument of transfer in form
reasonably satisfactory by the Company, duly executed by the registered Holder
thereof or by the duly appointed legal representative thereof or by a duly
authorized attorney-in-fact, (y) a certificate (signed by an officer of the
Holder if the Holder is a corporation) stating that each transferee is a
permitted transferee under this Section 3, and (z) an opinion of counsel,
reasonably satisfactory in form and substance to the Company, to the effect that
this Warrant or the Shares, as applicable, may be sold or otherwise transferred
without registration under the Act. Upon original issuance thereof, and until
such time as the same shall have been registered under the Act or sold pursuant
to Rule 144 promulgated thereunder (or any similar rule or regulation), each
certificate representing this Warrant or any part thereof shall bear the
following legend, unless in the opinion of counsel to the Company such legend is
no longer required by the Act:

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<PAGE>

          THIS WARRANT AND THE SHARES OF COMMON STOCK THAT ARE
          ISSUABLE UPON EXERCISE OF THE WARRANT MAY NOT BE SOLD,
          OFFERED FOR SALE, PLEDGED OR OTHERWISE TRANSFERRED UNLESS
          SUCH TRANSFER IS REGISTERED OR QUALIFIED UNDER THE
          SECURITIES ACT OF 1933, AS AMENDED, AND APPLICABLE STATE
          SECURITIES LAWS OR UNLESS THE COMPANY RECEIVES AN OPINION OF
          COUNSEL OR OTHER EVIDENCE REASONABLY SATISFACTORY TO IT TO
          THE EFFECT THAT SUCH REGISTRATION AND QUALIFICATION ARE NOT
          REQUIRED.

Upon any transfer of this Warrant or any part thereof in accordance with the
first sentence of this Section 3(a), the Company shall issue, in the name or
names specified by the Holder (including the Holder), a new Placement Agent's
Warrant or Warrants of like tenor and representing in the aggregate rights to
purchase the same number of Shares as are purchasable hereunder at such time.

                  (b) Any attempted transfer of this Warrant or any part thereof
in violation of this Section 3 shall be null and void ab initio.

         4. The Company covenants and agrees that all Shares which may be
purchased hereunder will, upon issuance and delivery against payment therefor of
the requisite purchase price, be duly and validly issued, fully paid and
nonassessable. The Company further covenants and agrees that, during the periods
within which this Warrant may be exercised, the Company will at all times have
authorized and reserved a sufficient number of shares of its Common Stock to
provide for the exercise of this Warrant.

         5. This Warrant shall not entitle the Holder to any voting rights or
other rights, including without limitation notice of meetings of other actions
or receipt of dividends, as a stockholder of the Company.

         6. (a) Except as provided in Section 6(b), the Company shall advise the
Holder or its permitted transferee, whether the Holder holds this Warrant or has
exercised this Warrant and holds Shares, by written notice at least four weeks
prior to the filing of any new registration statement thereto under the Act,
covering any equity securities of the Company, for its own account or for the
account of others, except for any registration statement filed on Form S-4 or
S-8 (or other comparable form), and will, during the five (5) year period from
the Issue Date, upon the request of the Holder, include in any such new
registration statement (the "Registration Statement") such information as may be
required to permit a public offering of, all or any of the Shares underlying
this Warrant (the "Registrable Securities").

                  (b) At any time during the five (5) year period beginning on
the Issue Date, a 50% Holder (as defined below) may request, on one occasion,
that the Company register under the Act any and all of the Registrable
Securities held by such 50% Holder, at the Company's expense (except as provided
below). Upon the receipt of any such notice, the Company will promptly, but no
later than four weeks after receipt of such notice, file a post-effective
amendment to any existing registration statement or a new registration statement
pursuant to the

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Act (such post-effective amendment or new registration statement, a "Demand
Registration Statement"), so that such designated Registrable Securities may be
publicly sold under the Act as promptly as practicable thereafter and the
Company shall, subject to Section 6(h), use reasonable best efforts to cause
such Demand Registration Statement to become effective (including the taking of
such reasonable steps as are necessary to obtain the removal of any stop order)
within 120 days after the receipt of such notice, provided, that such 50% Holder
shall furnish the Company with appropriate information in connection therewith
as the Company may reasonably request in writing. The 50% Holder may, at its
option, request the registration of any of Registrable Securities in a
registration statement made by the Company as contemplated by Section 6(a) or in
connection with a request made pursuant to this Section 6(b), in either case
prior to acquisition of the Shares issuable upon exercise of this Warrant.
Subject to Section 6(h), within ten days after receiving any such notice
pursuant to this Section 6(b), the Company shall give notice to any other
Holders of this Warrant, advising that the Company is proceeding with such
Demand Registration Statement and offering to include therein, pursuant to
Section 6(a), the Shares underlying that part of this Warrant held by the other
Holders, provided that they shall furnish the Company with such appropriate
information (relating to the intentions of such Holders) in connection therewith
as the Company shall reasonably request in writing.

                  (c) The term "50% Holder" as used in this Section 6 shall mean
the Holder(s) of at least 50% of this Warrant and/or the Shares underlying this
Warrant upon the initial issuance of this Warrant, as the same may have been
adjusted pursuant to Section 8.

                  (d) For so long as the Registrable Securities included in any
Registration Statement or Demand Registration Statement remain unsold, but in
any event not longer than 270 days after the date of effectiveness of such
Registration Statement or Demand Registration Statement (plus the number of
days, if any, that such Registration Statement or Demand Registration Statement
has been suspended pursuant to the provisions of Section 6(h)), the Company
shall, subject to Section 6(h), (i) maintain the effectiveness of such
Registration Statement or Demand Registration Statement; (ii) timely file all
reports required under the Securities Exchange Act of 1934, as amended, and the
rules and regulations of the Commission thereunder; (iii) file such
post-effective amendments to the Registration Statement or Demand Registration
Statement as may be necessary so that the Registration Statement or Demand
Registration Statement does not contain any misstatement of a material fact or
omit to state any material fact required to make the statements therein not
misleading; (iv) supply prospectuses and such other documents as any Holder
whose Registrable Securities are included in such Registration Statement or
Demand Registration Statement may reasonably request in order to facilitate the
public sale or other disposition of such Registrable Securities; (v) use its
reasonable best efforts to register and qualify any of the Registrable
Securities for sale in such jurisdictions within the United States (x) as any
such Holder designates and (y) with respect to which the Company obtained a
qualification in connection with its initial public offering, provided that the
nothing in this clause (v) shall require the Company to qualify to do business
as a foreign corporation or to file a general consent to service of process in
any jurisdiction in which it is not otherwise so qualified or required to file
such a consent at the time; and (vi) do any and all other acts and things which
may be necessary or desirable to enable any such Holder to consummate the public
sale or other disposition of the Registrable Securities included in the
Registration Statement or Demand Registration Statement, all at no expense to
such Holder or the Placement Agent (except as provided in the immediately
following sentence). All costs and expenses in

                                       4

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connection with any Registration Statement or Demand Registration Statement
shall be borne by the Company, except that the Holder(s) shall bear the fees of
their own counsel and any other advisors retained by them and any underwriting
discounts or sales or other commissions applicable to any of the Registrable
Securities sold by them. In connection with any Registration Statement or Demand
Registration Statement, the Company shall furnish indemnification in the manner
provided in Section 7 hereof, and each Holder whose Registrable Securities are
included therein shall furnish information and indemnification in the manner
provided in Section 7. Subject to Section 6(g), the Company shall have the right
to include additional shares of Common Stock to be issued and sold by the
Company in any Demand Registration Statement.

                  (e) Notwithstanding the foregoing set forth in this Section 6,
the Company shall not be required to include in any Registration Statement or
any Demand Registration Statement any Registrable Securities which in the
opinion of counsel to the Company (which opinion is reasonably acceptable to
counsel to the Placement Agent) would be saleable immediately without
restriction or limitation under Rule 144 (or its successor) if this Warrant was
exercised pursuant to Section 2(b) herein.

                  (f) If any registration pursuant to this Section 6 is in the
form of an underwritten offering, the Company will select and obtain the
investment banker or investment bankers and manager or managers that will
administer the offering. The Company shall (together with each Holder whose
Registrable Securities are included in such offering) enter into an underwriting
agreement in customary form with the managing underwriter selected for such
underwriting. If any Holder disapproves of the terms of the underwriting, it may
elect to withdraw therefrom by written notice to the Company and the managing
underwriter, and upon such withdrawal the original request of such Holder to
cause Registrable Securities to be registered shall not be deemed to constitute
a request for registration pursuant to Section 6(b), provided that the
withdrawal of one or more Holders shall not affect the determination of whether
any request made pursuant to Section 6(b) was made by a 50% Holder, and provided
further that if all Holders who have requested inclusion of their shares in a
Demand Registration pursuant to Section 6(b) withdraw their Registrable
Securities, then, notwithstanding anything to the contrary in this Warrant, any
Holders who request registration of Registrable Securities pursuant to Section
6(b) in the future shall be responsible for and pay all expenses incurred by the
Company in connection with such future registration.

                  (g)(i) In the event that any registration pursuant to Section
6(a) shall be in connection with an underwritten offering, and the managing
underwriter determines in good faith and advises in writing that the number of
Registrable Securities to be included in such offering, together with the number
of shares of Common Stock to be included in the Registration Statement by the
Company or other holders of the Company's securities with the right to request
inclusion in the Registration Statement, if any, exceeds the number of shares of
Common Stock that it is advisable to offer and sell at such time or would
interfere with the successful marketing of the Common Stock covered by the
Registration Statement, then priority for including shares of Common Stock in
the Registration Statement, up to the number advised by the managing
underwriter, shall be allocated first, to the Company and each other person who
has requested inclusion of shares of Common Stock pursuant to a "demand"
registration right, pro rata in proportion to the respective number of shares of
Common Stock to be included by them, and

                                       5

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second, to the extent of any remaining capacity as advised by the managing
underwriter, to the Holders requesting registration of their Registrable
Securities and each other person who has requested inclusion of shares of Common
Stock pursuant to a "piggyback" registration right, pro rata in proportion to
the respective number of shares of Common Stock (including Registrable
Securities) to be included by them. (ii) In the event that any registration
pursuant to Section 6(b) shall be in connection with an underwritten offering,
and the managing underwriter determines in good faith and advises in writing
that the number of Registrable Securities to be included in such offering,
together with the number of shares of Common Stock to be included in the Demand
Registration Statement by the Company or other holders of the Company's
securities with the right to request inclusion in the Demand Registration
Statement, if any, exceeds the number of shares of Common Stock that it is
advisable to offer and sell at such time or would interfere with the successful
marketing of the Common Stock covered by the Demand Registration Statement, then
priority for including shares of Common Stock in the Demand Registration
Statement, up to the number advised by the managing underwriter, shall be
allocated first, to the 50% Holder and each other person who has requested
inclusion of shares of Common Stock pursuant to a "demand" registration right,
pro rata in proportion to the respective number of shares of Common Stock to be
included by them, and second, to the extent of any remaining capacity as advised
by the managing underwriter, to the Company and each other person (including any
Holder who is not a 50% Holder and who requests inclusion of Registrable
Securities in the Demand Registration Statement pursuant to Section 6(a)) who
has requested inclusion of shares of Common Stock pursuant to a "piggyback"
registration right, pro rata in proportion to the respective number of shares of
Common Stock (including Registrable Securities) to be included by them.

                  (h) In any registration initiated by the Company or by any
person having "demand" registration rights (other than a 50% Holder exercising
such rights pursuant to Section 6(b)) in which Holders request inclusion of
their Registrable Securities pursuant to Section 6(a), if at any time after
giving notice of its intention to register securities and prior to the effective
date of the Registration Statement the Company or such other person shall
determine for any reason not to register or to delay registration of it
securities, the Company may, at its election, give written notice of such
determination to each Holder that has requested inclusion of Registrable
Securities in the Registration Statement and (x) in the case of a determination
not to register, shall be relieved of its obligation to register any Registrable
Securities in connection with such registration and (y) in the case of a
determination to delay registering, shall be permitted to delay registering any
Registrable Securities for the same period as the delay in registering such
other securities. If (i) at any time when a prospectus relating to Registrable
Securities is required to be delivered under the Act, the Company discovers
that, or any event occurs as a result of which, the prospectus (including any
supplement thereto) included in any Registration Statement or Demand
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omits to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading, or (ii) the Commission issues any
stop order suspending the effectiveness of any Registration Statement or
proceedings are initiated or threatened for that purpose, then the Company shall
promptly deliver a written notice to such effect to each Holder whose
Registrable Securities are included in such Registration Statement or Demand
Registration Statement, and each such Holder shall immediately upon receipt of
such notice discontinue its disposition of Registrable Securities pursuant to
such Registration Statement or Demand Registration

                                       6

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Statement until its receipt of the copies of the supplemented or amended
prospectus contemplated by the immediately following sentence and, if so
directed by the Company, shall deliver to the Company (at the Company's expense)
all copies, other than permanent file copies, then in such Holder's possession
of the prospectus or prospectus supplement relating to such Registrable
Securities current at the time of receipt of such notice. As promptly as
practicable following the event or discovery referred to in clause (i) of the
immediately preceding sentence, the Company shall prepare and furnish to the
Holders whose Registrable Securities are included in such Registration Statement
or Demand Registration Statement a reasonable number of copies of an amendment
or supplement of such prospectus so that, as thereafter delivered to purchasers
of such Registrable Securities, such prospectus shall not include an untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading. Notwithstanding
anything to the contrary in this Section 6 if the filing or maintenance of any
Registration Statement or Demand Registration Statement would require the
Company to make a disclosure that would, in the reasonable judgment of the
Company's Board of Directors, have a material adverse effect on the business,
operations, properties, prospects or financial condition of the Company or on
pending or imminent transactions, the Company shall have the right, exercisable
for a period not to exceed in the aggregate 45 consecutive calendar days in any
period of twelve consecutive months (the "Blackout Period") upon written notice
to the Holders, to delay the filing of any Registration Statement or Demand
Registration Statement or of any amendment thereto, to suspend its obligation to
maintain the effectiveness of any Registration Statement or Demand Registration
Statement and to suspend the use of any prospectus or prospectus supplement in
connection with any Registration Statement or Demand Registration Statement.
Each Holder agrees that upon receipt of any such notice from the Company, it
shall immediately cease all efforts to dispose of Registrable Securities
pursuant to such Registration Statement or Demand Registration Statement until
such time as the Company shall notify it of the end of such restrictions or, if
earlier, the expiration of the Blackout Period.

         7. (a) Whenever pursuant to Section 6 a Registration Statement or
Demand Registration Statement relating to any Shares issued upon exercise of
this Warrant is filed under the Act, amended or supplemented, the Company will
indemnify and hold harmless each Holder of the securities covered by such
Registration Statement or Demand Registration Statement, amendment or supplement
(such Holder being hereinafter called the "Distributing Holder"), and each
person, if any, who controls (within the meaning of the Act) the Distributing
Holder, and each underwriter (within the meaning of the Act) of such securities
and each person, if any, who controls (within the meaning of the Act) any such
underwriter, against any losses, claims, damages or liabilities, joint or
several, to which the Distributing Holder, any such controlling person or any
such underwriter may become subject, under the Act or otherwise, insofar as such
losses, claims, damages or liabilities, or actions in respect thereof, arise out
of or are based upon any untrue statement or alleged untrue statement of any
material fact contained in any such Registration Statement or Demand
Registration Statement as declared effective or any final prospectus
constituting a part thereof or any amendment or supplement thereto, or arise out
of or are based upon the omission or the alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading and will reimburse the Distributing Holder or such
controlling person or underwriter for any legal or other expense reasonably
incurred by them in connection with investigating or defending any such loss,
claim, damage, liability or action; provided, however, that the Company will not
be liable in any such

                                       7

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case to the extent that any such loss, claim, damage or liability arises out of
or is based upon an untrue statement or alleged untrue statement or omission or
alleged omission made in said Registration Statement or Demand Registration
Statement, said preliminary prospectus, said final prospectus or said amendment
or supplement in reliance upon and in conformity with written information
furnished by such Distributing Holder or any other Distributing Holder for use
in the preparation thereof and provided further, that the indemnity agreement
provided in this Section 7(a) with respect to any preliminary prospectus shall
not inure to the benefit of any Distributing Holder, controlling person of such
Distributing Holder, underwriter or controlling person of such underwriter from
whom the person asserting any losses, claims, charges, liabilities or litigation
based upon any untrue statement or alleged untrue statement of a material fact
or omission or alleged omission to state therein a material fact, received such
preliminary prospectus, if a copy of the prospectus in which such untrue
statement or alleged untrue statement or omission or alleged omission was
corrected has not been sent or given to such person within the time required by
the Act and the rules and regulations of the Commission thereunder.

                  (b) The Distributing Holder will indemnify and hold harmless
the Company, each of its directors, each of its officers who have signed said
Registration Statement or Demand Registration Statement and such amendments and
supplements thereto, and each person, if any, who controls the Company (within
the meaning of the Act) against any losses, claims, damages or liabilities,
joint or several, to which the Company or any such director, officer or
controlling person may become subject, under the Act or otherwise, insofar as
such losses, claims, damages or liabilities, or actions in respect thereof,
arise out of or are based upon any untrue or alleged untrue statement of any
material fact contained in said Registration Statement or Demand Registration
Statement, said preliminary prospectus, said final prospectus, or said amendment
or supplement, or arise out of or are based upon the omission or the alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, in each case to the
extent, but only to the extent, that such loss, claim, damage or liability
arises out of or is based upon an untrue statement or alleged untrue statement
or omission or alleged omission made in said Registration Statement or Demand
Registration Statement, said preliminary prospectus, said final prospectus or
said amendment or supplement in reliance upon and in conformity with written
information furnished by such Distributing Holder for use in the preparation
thereof; and will reimburse the Company or any such director, officer or
controlling person for any legal or other expenses reasonably incurred by them
in connection with investigating or defending any such loss, claim, damage,
liability or action.

                  (c) Promptly after receipt by an indemnified party under this
Section 7 of notice of the commencement of any action, such indemnified party
will, if a claim in respect thereof is to be made against an indemnifying party
under this Section 7, notify the indemnifying party in writing of the
commencement thereof, but the omission so to notify the indemnifying party will
not relieve it from any liability which it may have to any indemnified party for
indemnity or contribution to the extent it is not prejudiced as a proximate
result of such failure. In case any such action is brought against any
indemnified party, and such indemnified party seeks or intends to seek indemnity
from an indemnifying party, the indemnifying party will be entitled to
participate in, and, to the extent that it shall elect, jointly with any other
indemnifying party similarly notified, by written notice delivered to the
indemnified party promptly after receiving the aforesaid notice from such
indemnified party, to assume the defense thereof with

                                       8

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counsel reasonably satisfactory to such indemnified party; provided, however, if
the defendants in any such action include both the indemnified party and the
indemnifying party and the indemnified party shall have reasonably concluded
that a conflict may arise between the positions of the indemnifying party and
the indemnified party in conducting the defense of any such action or that there
may be legal defenses available to it and/or other indemnified parties which are
different from or additional to those available to the indemnifying party, the
indemnified party or parties shall have the right to select separate counsel to
assume such legal defenses and to otherwise participate in the defense of such
action on behalf of such indemnified party or parties. Upon receipt of notice
from the indemnifying party to such indemnified party of such indemnifying
party's election so to assume the defense of such action and approval by the
indemnified party of counsel (which approval shall not be unreasonably withheld
or delayed), the indemnifying party will not be liable to such indemnified party
under this Section 7 for any legal or other expenses subsequently incurred by
such indemnified party in connection with the defense thereof unless: (i) the
indemnified party shall have employed separate counsel in accordance with the
proviso to the next preceding sentence (it being understood, however, that the
indemnifying party shall not be liable for the expenses of more than one
separate counsel (together with local counsel), representing the indemnified
parties who are parties to such action); (ii) the indemnifying party shall not
have employed counsel satisfactory to the indemnified party to represent the
indemnified party within a reasonable time after notice of commencement of the
action; or (iii) the indemnifying party has authorized the employment of counsel
for the indemnified party satisfactory to the indemnified party at the expense
of the indemnifying party, in each of which cases the fees and expenses of
counsel shall be at the expense of the indemnifying party.

                  (d) The indemnifying party under this Section 7 shall not be
liable for any settlement of any proceeding effected without its written
consent, which consent shall not be unreasonably withheld or delayed, but if
settled with such consent or if there be a final judgment for the plaintiff, the
indemnifying party agrees to indemnify the indemnified party against any loss,
claim, damage, liability or expense by reason of such settlement or judgment. No
indemnifying party shall, without the prior written consent of the indemnified
party, effect any settlement, compromise or consent to the entry of judgment in
any pending or threatened action, suit or proceeding in respect of which any
indemnified party is or could have been a party and indemnity was or could have
been sought hereunder by such indemnified party, unless such settlement,
compromise or consent includes: (i) an unconditional release of such indemnified
party from all liability on claims that are the subject matter of such action,
suit or proceeding; and (ii) does not include a statement as to or an admission
of fault, culpability or a failure to act by or on behalf of any indemnified
party.

                  (e) Any losses, claims, damages, liabilities or expenses for
which an indemnified party is entitled to indemnification or contribution under
this Section 7 shall be paid by the indemnifying party to the indemnified party
as such losses, claims, damages, liabilities or expenses are incurred, but in
all cases, no later than forty-five (45) days after invoice to the indemnifying
party.

                   (f) If the indemnification provided for in this Section 7 is
unavailable to or insufficient to hold harmless an indemnified party under
Section 7(a) or 7(b) above in respect of

                                       9

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any losses, claims, damages or liabilities (or actions or proceedings in respect
thereof) then each indemnifying party shall contribute to the aggregate amount
paid or payable by such indemnified party in such proportion as is appropriate
to reflect the relative fault of such indemnifying party on the one hand and the
Distributing Holder on the other in connection with the statements or omissions
which resulted in such losses, claims, damages or liabilities (or actions or
proceedings in respect thereof), as well as any other relevant equitable
considerations. The relative fault shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission or alleged omission to state a material fact relates to
information supplied by the Company or the "control" stockholders on the one
hand or the Distributing Holder on the other and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission.

         The Company and each Distributing Holder agree that it would not be
just and equitable if contributions pursuant to this Section 7(f) were
determined by pro rata allocation or by any other method of allocation which
does not take account of the equitable considerations referred to above in this
Section 7(f). The amount paid or payable by an indemnified party as a result of
the losses, claims, damages or liabilities (or actions or proceedings in respect
thereof) referred to above in this Section 7(f) shall be deemed to include any
legal or other expenses reasonably incurred by such indemnified party in
connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this Section 7(f): (i) each Distributing
Holder shall not be required to contribute any amount in excess of the amount of
proceeds received by such Holder from sale(s) of such Holder's Shares pursuant
to the Registration Statement or Demand Registration Statement; and (ii) no
person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Act) shall be entitled to contribution from any person who was not
guilty of such fraudulent misrepresentation.

         8. The Exercise Price in effect at the time and the number and kind of
securities purchasable upon the exercise of the Warrant shall be subject to
adjustment from time to time upon the happening of certain events as follows:

                  (a) In case the Company shall (i) declare a dividend or make a
distribution on its outstanding shares of Common Stock in shares of Common
Stock, (ii) subdivide or reclassify its outstanding shares of Common Stock into
a greater number of shares, (iii) combine or reclassify its outstanding shares
of Common Stock into a smaller number of shares, or (iv) enter into any
transaction whereby the outstanding shares of Common Stock of the Company are at
any time changed into or exchanged for a different number or kind of shares or
other security of the Company or of another corporation through reorganization,
merger, consolidation, liquidation or recapitalization, then appropriate
adjustments in the number of Shares (or other securities for which such Shares
have previously been exchanged or converted) subject to this Warrant shall be
made and the Exercise Price in effect at the time of the record date for such
dividend or distribution or of the effective date of such subdivision,
combination, reclassification, reorganization, merger, consolidation,
liquidation or recapitalization shall be proportionately adjusted so that the
Holder of this Warrant exercised after such date shall be entitled to receive
the aggregate number and kind of shares of Common Stock which, if this Warrant
had been exercised by such Holder immediately prior to such date, the Holder
would have been entitled to receive upon such dividend, distribution,
subdivision, combination, reclassification, reorganization, merger,
consolidation, liquidation or recapitalization. For example, if the Company
declares a 2 for 1 stock distribution and the Exercise Price hereof

                                       10

<PAGE>

immediately prior to such event was $3.00 per Share and the number of Shares
issuable upon exercise of this Warrant was 10,000, the adjusted Exercise Price
immediately after such event would be $1.50 per Share and the adjusted number of
Shares issuable upon exercise of this Warrant would be 20,000. Such adjustment
shall be made successively whenever any event listed above shall occur.

                  (b) In case the Company shall fix a record date for the
issuance of rights or warrants to all holders of its Common Stock entitling them
to subscribe for or purchase shares of Common Stock (or securities convertible
into Common Stock) at a price (the "Subscription Price") (or having a conversion
price per share) less than the current market price per share of Common Stock
basis as determined pursuant to Section 8(e) on such record date, the Exercise
Price shall be adjusted so that the same shall equal the price determined by
multiplying the same by a fraction, the numerator of which shall be the sum of
the number of shares of Common Stock outstanding on the record date mentioned
below and the number of additional shares of Common Stock which the aggregate
offering price of the total number of shares of Common Stock so offered (or the
aggregate conversion price of the convertible securities so offered) would
purchase at the current market price per share of Common Stock on such record
date, and the denominator of which shall be the sum of the number of shares of
Common Stock outstanding on the record date mentioned below and the number of
additional shares of Common Stock offered for subscription or purchase (or into
which the convertible securities so offered are convertible). Such adjustment
shall be made successively whenever such rights or warrants are issued and shall
become effective immediately after the record date for the determination of
stockholders entitled to receive such rights or warrants; and to the extent that
shares of Common Stock are not delivered (or securities convertible into Common
Stock are not delivered) after the expiration of such rights or warrants the
Exercise Price shall be readjusted to the Exercise Price which would then be in
effect had the adjustments made upon the issuance of such rights or warrants
been made upon the basis of delivery of only the number of shares of Common
Stock (or securities convertible into Common Stock) actually delivered. This
Section 8(b) shall not apply to the occurrence of a "Distribution Date" under
the Rights Agreement.

                  (c) In case the Company shall hereafter distribute to all
holders of its Common Stock evidences of its indebtedness or assets (excluding
cash dividends or distributions and dividends or distributions referred to in
Section 8(a) above) or subscription rights or warrants (excluding those referred
to in Section 8(b) above), then in each such case the Exercise Price shall be
adjusted by multiplying the same, by a fraction, the numerator of which shall be
the total number of shares of Common Stock then outstanding multiplied by the
current market price per share of Common Stock (as defined in Section 8(e)
below), less the fair market value (as determined by the Company's Board of
Directors) of said assets, or evidences of indebtedness so distributed or of
such rights or warrants, and the denominator of which shall be the total number
of shares of Common Stock outstanding multiplied by such current market price
per share of Common Stock. Such adjustment shall be made whenever any such
distribution is made and shall become effective immediately after the record
date for the determination of stockholders entitled to receive such distribution
and to the extent that any subscription rights or warrants are not exercised
before the expiration of such rights or warrants the Exercise Price shall be
readjusted to the Exercise Price which would then be in effect had the
adjustments made upon the issuance of such rights or warrants been made upon the
basis of delivery of only the number

                                       11

<PAGE>

of rights or warrants actually exercised. This Section 8(c) shall not apply to
the occurrence of a "Distribution Date" under the Rights Agreement.

                  (d) Whenever the Exercise Price payable upon exercise of this
Warrant is adjusted pursuant to Sections 8(a), (b) or (c) above, the number of
Shares purchasable upon exercise of this Warrant shall simultaneously be
adjusted by multiplying the number of Shares issuable upon exercise of this
Warrant by the Exercise Price in effect immediately prior to such adjustment and
dividing the product so obtained by the Exercise Price, as adjusted.

                  (e) For the purpose of any computation under Section 8(c)
above, the current market price per share of Common Stock at any date shall be
deemed to be the closing price on the Trading Day immediately preceding the date
as of which the current market price is being determined, provided that if the
Common Stock is not then listed on any market or exchange, then the current
market price shall be the average of the closing bid prices for the Common Stock
on the OTC Bulletin Board, or, if such is not available, the Pink Sheets LLC
(formerly the National Quotation Bureau), or otherwise the average of the
closing bid prices for the Common Stock quoted by two market-makers of the
Common Stock, or otherwise such Market Price shall be the fair market value of
one share of Common Stock as reasonably determined in good faith by the
Corporation and the Holders. "Trading Day" shall mean any day on which the
principal United States securities exchange or trading market on which the
Common Stock is listed or traded (the "Principal Market") as reported by
Bloomberg Financial Markets is open for trading. "Closing price" shall mean the
last sale price for the Common Stock on the Principal Market on any particular
Trading Day.

                  (f) No adjustment in the Exercise Price shall be required
unless such adjustment would require an increase or decrease of at least five
cents ($0.05) in such price; provided, however, that any adjustments which may
by reason of this Section 8(f) are not required to be made shall be carried
forward and taken into account in any subsequent adjustment required to be made
hereunder. All calculations under this Section 8 shall be made to the nearest
cent or to the nearest one-hundredth of a share, as the case may be. Anything in
this Section 8 to the contrary notwithstanding, the Company shall be entitled,
but shall not be required, to make such changes in the Exercise Price, in
addition to those required by this Section 8, as it shall determine, in its sole
discretion, to be advisable in order that any dividend or distribution in shares
of Common Stock, or any subdivision, reclassification or combination of Common
Stock, hereafter made by the Company shall not result in any Federal income tax
liability to the holders of the Common Stock or securities convertible into
Common Stock.

                  (g) Whenever the Exercise Price is adjusted, as herein
provided, the Company shall promptly cause a notice setting forth the adjusted
Exercise Price and adjusted number of Shares issuable upon exercise of this
Warrant to be mailed to the Holder, at its address set forth herein, and shall
cause a certified copy thereof to be mailed to the Company's transfer agent, if
any. The Company may retain a firm of independent certified public accountants
selected by the Board of Directors (who may be the regular accountants employed
by the Company) to make any computation required by this Section 8, and a
certificate signed by such firm shall be conclusive evidence of the correctness
of such adjustment.

                                       12

<PAGE>

                  (h) In the event that at any time, as a result of an
adjustment made pursuant to the provisions of this Section 8, the Holder of this
Warrant thereafter shall become entitled to receive any shares of the Company
other than Common Stock, thereafter the number of such other shares so
receivable upon exercise of this Warrant shall be subject to adjustment from
time to time in a manner and on terms as nearly equivalent as practicable to the
provisions with respect to the Common Stock contained in Sections 8(a) to (f),
inclusive, above.

         9. This Warrant shall be governed by and in accordance with the laws of
the State of Delaware without regard to conflicts of laws principles thereof.

         10. In case of any consolidation of the Company with, or merger of the
Company into, any other entity, or in case of any sale or conveyance of all or
substantially all of the assets of the Company other than in connection with a
plan of complete liquidation of the Company at any time prior to the Expiration
Date, then as a condition of such consolidation, merger or sale or conveyance,
the Company shall give written notice of consolidation, merger, sale or
conveyance to the Holder and, from and after the effective date of such
consolidation, merger, sale or conveyance this Warrant shall represent only the
right to receive the consideration that would have been issuable in respect of
the Shares underlying this Warrant in such consolidation, merger, sale or
conveyance had this Warrant been exercised in full immediately prior to such
effective time and the Holder shall have no further rights under this Warrant
other than the right to receive such consideration.

                                       13

<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by
its duly authorized officers under its corporate seal, and this Warrant to be
dated [      ].

                                                  BIOPURE CORPORATION

                                                  By:
                                                      ---------------------
                                                      Name: Thomas A. Moore
                                                      Title: President

Attest:

__________________________
Jane Kober
Secretary

                                       14

<PAGE>

                                  PURCHASE FORM

                  (To be signed only upon exercise of Warrant)

         The undersigned, the holder of the foregoing Placement Agent's Warrant,
hereby irrevocably elects to exercise the purchase rights represented by such
Warrant for, and to purchase thereunder, _______________ Shares of Class A
Common Stock, $0.01 par value per share (the "Shares"), of BIOPURE CORPORATION
and either

         [ ]      tenders herewith payment of the aggregate Exercise Price in
                  respect of the Shares in full, in the amount of $_________; or

         [ ]      elects pursuant to Section 2(b) of such Warrant to convert
                  such Warrant into Common Stock on a cashless exercise basis;
                  and

requests that the certificates for the Shares issued in the name(s) of, and
delivered to _________________, whose address(es) is (are):

Dated: _______________, ____

                                           By: _______________________________

                                           ___________________________________

                                           ___________________________________
                                           Address

<PAGE>

                                  TRANSFER FORM

         (To be signed only upon transfer of Placement Agent's Warrant)

         For value received, the undersigned hereby sells, assigns, and
transfers unto ______________________________ the right to purchase Shares
represented by the foregoing Placement Agent's Warrant to the extent of
__________ Shares, and appoints _________________________ attorney to transfer
such rights on the books of Biopure Corporation, with full power of substitution
in the premises. The undersigned believes that each transferee is a permitted
transferee under Section 3 of this Warrant.

Dated: _______________, ____

                                           By: _______________________________

                                           ___________________________________

                                           ___________________________________
                                           Address

In the presence of:

_________________________