EXHIBIT 4.4


THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES
HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"ACT"), AND THEY MAY NOT BE OFFERED, SOLD, PLEDGED, HYPOTHECATED, ASSIGNED OR
TRANSFERRED EXCEPT (i) PURSUANT TO A REGISTRATION STATEMENT UNDER THE ACT WHICH
HAS BECOME EFFECTIVE AND IS CURRENT WITH RESPECT TO THESE SECURITIES, OR (ii)
PURSUANT TO A SPECIFIC EXEMPTION FROM REGISTRATION UNDER THE ACT BUT ONLY UPON A
HOLDER HEREOF FIRST HAVING OBTAINED THE WRITTEN OPINION OF COUNSEL TO THE
COMPANY, OR OTHER COUNSEL REASONABLY ACCEPTABLE TO THE COMPANY, THAT THE
PROPOSED DISPOSITION IS CONSISTENT WITH ALL APPLICABLE PROVISIONS OF THE ACT AS
WELL AS ANY APPLICABLE "BLUE SKY" OR SIMILAR STATE SECURITIES LAW.


                          BOSTON LIFE SCIENCES, INC.

                    Warrant for the Purchase of Shares of 
                    -------------------------------------
                                 Common Stock
                                 ------------


NO. BLSI - J-33                                                  97,150   SHARES


FOR VALUE RECEIVED, BOSTON LIFE SCIENCES, INC., A Delaware corporation (the
"COMPANY"), hereby certifies that The Tail Wind Fund, Ltd. or its permitted
assigns, is entitled to purchase from the Company, at any time or from time to
time commencing on February 5, 1999 (the "Initial Exercise Date") and prior to
5:00 P. M., New York City time, on February 10, 2004 (the "Termination Date"),
97,150 fully paid and non-assessable shares of the Common Stock, $.01 par value
per share, of the Company for an aggregate purchase price of $467,291.50
computed on the basis of $4.810 per share [equal to the Closing Bid Price for
the Common Stock on the NASDAQ Stock Market on the Trading Day prior to the
closing date]. (Hereinafter, (i) said Common Stock, together with any other
equity securities which may be issued by the Company with respect thereto or in
substitution therefor, is referred to as the "COMMON STOCK", (ii) the shares of
the Common Stock purchasable hereunder or under any other Warrant (as
hereinafter defined) are referred to as the "WARRANT SHARES", (iii) the
aggregate purchase price payable for the Warrant Shares hereunder is referred to
as the "AGGREGATE WARRANT PRICE", (iv) the price payable for each of the Warrant
Shares hereunder is referred to as the "PER SHARE WARRANT PRICE", (v) this
Warrant, all similar Warrants issued on the date hereof and all warrants
hereafter issued in exchange or substitution for this Warrant or such similar
Warrants are referred to as the "WARRANTS" and (vi) the holder of this Warrant
is referred to as the "HOLDER" and the holder of this Warrant and all other
Warrants or Warrant Shares issued upon the exercise of any Warrant are referred
to as the "HOLDERS"). The Per Share Warrant Price and the number of Warrant
Shares purchasable on exercise of this Warrant shall be subject to adjustment as
hereinafter provided.

                                       1

 
     1.   EXERCISE OF WARRANT
          -------------------

          (a)  This Warrant may be exercised, in whole at any time or in part
from time to time, commencing on the Initial Exercise Date and prior to 5:00
P.M. New York City time, on the Termination Date by the holder by the surrender
of this Warrant (with the subscription form at the end hereof duly executed) at
the address set forth in Subsection 9(a) hereof, together with proper payment of
the Aggregate Warrant Price, or the proportionate part thereof if this Warrant
is exercised in part, with payment for Warrant Shares made by certified or
official bank check payable to the order of the Company; or

          (b)  If this Warrant is exercised in part, this Warrant must be
exercised for a number of whole shares of the Common Stock and the Holder is
entitled to receive a new Warrant covering the Warrant Shares which have not
been exercised and setting forth the proportionate part of the Aggregate Warrant
Price applicable to such Warrant Shares. Upon surrender of this Warrant, the
Company will (i) within a reasonable time but not longer than five (5) business
days issue a certificate or certificates in the name of the Holder for the
largest number of whole shares of the Common Stock to which the Holder shall be
entitled and, if this Warrant is exercised in whole, in lieu of any fractional
share of the Common Stock to which the Holder shall be entitled, pay to the
Holder cash in an amount equal to the fair value of such fractional share
(determined in such reasonable manner as the Board of Directors of the Company
shall determine), and (ii) deliver the other securities and properties
receivable upon the exercise of this Warrant, if any, or the proportionate part
thereof if this Warrant is exercised in part, pursuant to the provisions of this
Warrant.

     2.   RESERVATION OF WARRANT SHARES; LISTING.  The Company agrees that,
          --------------------------------------                           
prior to the expiration of this Warrant, the Company will at all times (a) have
authorized and in reserve, and will keep available, solely for issuance or
delivery upon the exercise of this Warrant, the shares of the Common Stock and
other securities and properties as from time to time shall be receivable upon
the exercise of this Warrant, free and clear of all restrictions on sale or
transfer, except for the restrictions on sale or transfer set forth in the
Securities Act of 1933, as amended (the "ACT"), and restrictions created by or
on behalf of the Holder, and free and clear of all preemptive rights and rights
of first refusal; and (b) if the Company prepares and files a registration
statement covering the shares of Common Stock issued or issuable upon exercise
of this Warrant with the Securities and Exchange Commission (the "SEC") which
registration statement is declared effective by the SEC under the Act and the
Company lists its Common Stock on any national securities exchange, it will use
its best efforts to cause the shares of Common Stock subject to this Warrant to
be listed on such exchange.

     3.   PROTECTION AGAINST DILUTION.
          --------------------------- 

          (a)  If, at any time or from time to time after the date of the
Warrant, the Company shall issue or distribute to the holders of shares of
Common Stock evidence of its indebtedness, any other securities of the Company
or any cash property or other assets (excluding a subdivision, combination or
reclassification, or dividend or distribution payable in shares of Common Stock,
referred to in Subsection 3(b), and also excluding cash dividends or cash
distributions paid out of net profits legally available therefor in the full
amount thereof, together with the value of other dividends and distributions
made substantially concurrently therewith or pursuant to a plan which includes
payment thereof, which is equivalent to not more than 5% of the Company's net
worth) (any such non-excluded event being herein called a "SPECIAL DIVIDEND"),
the Per Share Warrant Price shall be adjusted by multiplying the Per Share
Warrant Price then in effect by a fraction, the numerator of which shall be the
then current Market Price of the Common Stock less the fair market value (as
determined in good faith by the 

                                       2

 
Company's Board of Directors) of the evidence of indebtedness, cash, securities
or property, or other assets issued or distributed in such Special Dividend
applicable to one share of Common Stock and the denominator of which shall be
the then current Market Price of the Common Stock. An adjustment made pursuant
to this Subsection 3(a) shall become effective immediately after the record date
of any such Special Dividend.

          (b)  In case the Company shall hereafter (i) pay a dividend or make a
distribution on its capital stock in shares of Common Stock, (ii) subdivide its
outstanding shares of Common Stock into a greater number of shares, (iii)
combine its outstanding shares of Common Stock into a smaller number of shares
or (iv) issue by reclassification of its Common Stock any shares of capital
stock of the Company, the Per Share Warrant Price shall be adjusted to be equal
to a fraction, the numerator of which shall be the Aggregate Warrant Price and
the denominator of which shall be the number of shares of Common Stock or other
capital stock of the Company which he would have owned immediately following
such action had such Warrant been exercised immediately prior thereto. An
adjustment made pursuant to this Subsection 3(b) shall become effective
immediately after the record date in the case of a dividend or distribution and
shall become effective immediately after the effective date in the case of a
subdivision, combination or reclassification.

          (c)  No adjustment in the Per Share Warrant Price shall be required in
the case of the issuance by the Company of (a) Common Stock pursuant to the
exercise of any Warrant, (b) options or warrants to purchase Common Stock
(including the exercise thereof) issued or sold to employees, officers or
directors of or consultants and advisers to the Company or any subsidiary
thereof, and (c) shares of Common Stock issued or sold pursuant to stock
purchase or stock option plans or other similar arrangements that are approved
by the Company's Board of Directors.

          (d)  In case of any capital reorganization or reclassification, or any
consolidation or merger to which the Company is a party other than a merger or
consolidation in which the Company is the continuing corporation, or in case of
any sale or conveyance to another entity of the property of the Company as an
entirety or substantially as an entirety, or in the case of any statutory
exchange of securities with another corporation (including any exchange effected
in connection with a merger of a third corporation into the Company), the Holder
of this Warrant shall have the right thereafter to receive on the exercise of
this Warrant the kind and amount of securities, cash or other property which the
Holder would have owned or have been entitled to receive immediately after such
reorganization, reclassification, consolidation, merger, statutory exchange,
sale or conveyance had this Warrant been exercised immediately prior to the
effective date of such reorganization, reclassification, consolidation, merger,
statutory exchange, sale or conveyance and in any such case, if necessary,
appropriate adjustment shall be made in the application of the provisions set
forth in this Section 3 with respect to the rights and interests thereafter of
the Holder of this Warrant to the end that the provisions set forth in this
Section 3 shall thereafter correspondingly be made applicable, as nearly as may
reasonably be, in relation to any shares or other securities or property
thereafter deliverable on the exercise of this Warrant. The above provisions of
this Subsection 3(d) shall similarly apply to successive reorganizations,
reclassifications, consolidations, mergers, statutory exchanges, sales or
conveyances. The issuer of any shares of stock or other securities or property
thereafter deliverable on the exercise of this Warrant shall be responsible for
all of the agreements and obligations of the Company hereunder. Notice of any
such reorganization, reclassification, consolidation, merger, statutory
exchange, sale or conveyance and of said provisions so proposed to be made,
shall be mailed to the Holders of the Warrants not less than 30 days prior to
such event. A sale of all or substantially all of the assets of the Company for
a

                                       3

 
consideration consisting primarily of securities shall be deemed a consolidation
or merger for the foregoing purposes.

          (e) In case any event shall occur as to which the other provisions of
this Section 3 are not strictly applicable but as to which the failure to make
any adjustment would not fairly protect the purchase rights represented by this
Warrant in accordance with the essential intent and principles hereof then, in
each such case, the Holders of Warrants representing the right to purchase a
majority of the Warrant Shares subject to all outstanding Warrants may appoint a
firm of independent public accountants of recognized national standing
reasonably acceptable to the Company, which shall give their opinion as to the
adjustment, if any, on a basis consistent with the essential intent and
principles established herein, necessary to preserve the purchase rights
represented by the Warrants. Upon receipt of such opinion, the Company will
promptly mail a copy thereof to the Holder of this Warrant and shall make the
adjustments described therein. The fees and expenses of such independent public
accountants shall be borne by the Company.

          (f) If and whenever an adjustment to the Purchase Price of the Shares
is made pursuant to Section 7.1 of the Purchase Agreement, then the Per Share
Warrant Price shall be adjusted downward to equal such lower price.

          (g) No adjustment in the Per Share Warrant Price shall be required
unless such adjustment would require an increase or decrease of at least $0.05
per share of Common Stock; provided, however, that any adjustments which by
                           --------  -------                               
reason of this Subsection 3(g) are not required to be made shall be carried
forward and taken into account in any subsequent adjustment; provided, further,
                                                             -------- -------- 
however, that adjustments shall be required and made in accordance with the
provisions of this Section 3 (other than this Subsection 3(g)) not later than
such times as may be required in order to preserve the tax-free nature of a
distribution to the Holder of this Warrant or Common Stock issuable upon the
exercise hereof.  All calculations under this section 3 shall be made to the
nearest cent or to the nearest 1/100th of share, as the case may be.  Anything
in this Section 3 to the contrary notwithstanding, the Company shall be entitled
to make such reductions in the Per Share Warrant Price, in addition to those
required by this Section 3, as it in its discretion shall deem to be advisable
in order that any stock dividend, subdivision of shares or distribution of
rights to purchase stock or securities convertible or exchangeable for stock
hereafter made by the Company to its stockholders shall not be taxable.

          (h) If the Board of Directors of the Company shall declare any
dividend or other distribution with respect to the Common Stock other than a
cash distribution out of earned surplus, the Company shall mail notice thereof
to the Holders of the Warrants not less than 15 days prior to the record date
fixed for determining stockholders entitled to participate in such dividend or
other distribution.

          (i) If, as a result of an adjustment made pursuant to this Section 3,
the Holder of any Warrant thereafter surrendered for exercise shall become
entitled to receive shares of two or more classes of capital stock or shares of
Common Stock and other capital stock of the Company, the Board of Directors
(whose reasonable determination shall be conclusive and shall be described in a
written notice to the Holder of any Warrant promptly after such adjustment)
shall determine the allocation of the adjusted Per Share Warrant Price between
or among shares or such classes of capital stock or shares of Common Stock and
other capital stock.

     4.   FULLY PAID STOCK; TAXES.  The Company agrees that the shares of the
          -----------------------                                            
Common Stock represented by each and every certificate of Warrant Shares
delivered on the exercise of this Warrant will be validly issued and
outstanding, fully paid and nonassessable, and not subject 

                                       4

 
to preemptive rights or rights of first refusal, and the Company will take all
such actions as may be necessary to assure that the par value or stated value,
if any, per share of the Common Stock is at all times equal to or less than the
then Per Share Warrant Price. The Company further covenants and agrees that it
will pay, when due and payable, any and all Federal and State stamp, original
issue or similar taxes which may be payable in respect of the issue of any
Warrant Share or any certificate thereof.

     5.   REGISTRATION UNDER SECURITIES ACT OF 1933. The initial holder of this
          -----------------------------------------                             
Warrant is entitled to the benefit of certain registration rights in respect of
the Warrant Shares as provided in the Registration Rights Agreement dated as of
February 5, 1999.

     6.   LIMITED TRANSFERABILITY.  This Warrant may not be sold, transferred,
          -----------------------                                            
assigned or hypothecated by the Holder (a) except in compliance with the
provisions of the Act and the applicable state securities "blue sky" laws, and
(b) until the first anniversary hereof except (i) to any successor firm or
corporation of The Tail Wind Fund, Ltd., (ii) to any of the officers or
employees of The Tail Wind Fund, Ltd., or any such successor firm or (iii) in
the case of an individual, pursuant to such individual's last will and testament
or the laws of descent and distribution, and is so transferable only upon the
books of the Company which it shall cause to be maintained for such purpose. The
Company may treat the registered Holder of this Warrant as he or it appears on
the Company's books at any time as the Holder for all purposes. The Company
shall permit any Holder of a Warrant or his duly authorized attorney, upon
written request during ordinary business hours, to inspect and copy or make
extracts from its books showing the registered holders of Warrants. All warrants
issued upon the transfer or assignment of this Warrant will be dated the same
date as this Warrant, and all rights of the holder thereof shall be identical to
those of the Holder.

     7.   LOSS, ETC., OF WARRANT.  Upon receipt of evidence reasonably
          ----------------------                                      
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant, and of indemnity reasonably satisfactory to the Company, if lost,
stolen or destroyed, and upon surrender and cancellation of this Warrant, if
mutilated, the Company shall execute and deliver to the Holder a new Warrant of
like date, tenor and denomination.

     8.   WARRANT HOLDER NOT SHAREHOLDER.  Except as otherwise provided herein,
          ------------------------------                                       
this Warrant does not confer upon the Holder any right to vote or to consent to
or receive notice as a stockholder of the Company, as such, in respect of any
matters whatsoever, or any other rights or liabilities as a stockholder, prior
to the exercise hereof.

     9.   COMMUNICATION.  No notice or other communication under this Warrant
          -------------                                                      
shall be effective unless, but any notice or other communication shall be
effective and shall be deemed to have been given if, the same is in writing and
is mailed by first-class mail, postage prepaid, addressed to:

          (a)  The Company at 31 Newbury Street, Suite 300, Boston, MA 02116 or
other address as the Company has designated in writing to the Holder, or

          (b)  the Holder at The Tail Wind Fund, Ltd., European American
Securities, Inc., One Reagent Street, 4/th/ Floor, London, SW1Y 4NS, England
Attn: Mr. David Crook and The Tail Wind Fund, Ltd., Windermere House, 404 East
Bay Street, PO Box SS-5539, Nassau, Bahamas Attn: J. McCarroll or other such
address as the Holder has designated in writing to the Company.

                                       5

 
     10.  HEADINGS. The headings of this Warrant have been inserted as a matter
          --------                                                             
of convenience and shall not affect the construction hereof.

     11.  APPLICABLE LAW.  This Warrant shall be governed by and construed in
          --------------                                                     
accordance with the law of the State of Delaware without giving effect to the
principles of conflicts of law thereof.

IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its
President and attested to by its Secretary on the dates indicated below.


                                    BOSTON LIFE SCIENCES, INC.


                                         
                                    By: /s/ David Hillson
                                        -----------------------
                                        David Hillson
                                        President

                                    Date: February 5, 1999
                                         ----------------------


ATTEST:

/s/ Joseph Hernon
- -------------------------
Secretary

Date: February 5, 1999
     --------------------

                                       6

 
                                 SUBSCRIPTION
                                 ------------

          The undersigned, _______________________, pursuant to the provisions
of the foregoing Warrant, hereby agrees to Subscribe for and purchase __________
shares of the Common Stock, par value $.01 per share, of Boston Life Sciences,
Inc. covered by said Warrant, and makes payment therefor in full at the price
per share provided by said Warrant.


Dated:__________________                Signature:____________________________

                                        Address:  ____________________________

                                                  ____________________________



                                  ASSIGNMENT
                                  ----------

          FOR VALUE RECEIVED______________ hereby sells, assigns and transfers
unto ______________________the foregoing Warrant and all right evidenced
thereby, and does irrevocably constitute and appoint __________________________,
attorney, to transfer said Warrant on the books of Boston Life Sciences, Inc.

Dated:__________________                Signature:____________________________
                                                  
                                        Address:  ____________________________
                                                  
                                                  ____________________________


                               PARTIAL ASSIGNMENT
                               ------------------

          FOR VALUE RECEIVED __________________ hereby assigns and transfers
unto ________________________ the right to purchase ___________ shares of the
Common Stock, par value $.01 per share, of Boston Life Sciences, Inc. covered by
the foregoing Warrant, and a proportionate part of said Warrant and the rights
evidenced thereby, and does irrevocably constitute and appoint ________________,
attorney, to transfer that part of said Warrant on the books of Boston Life
Sciences, Inc.


Dated:__________________                Signature:____________________________
                                                  
                                        Address:  ____________________________
                                                  
                                                  ____________________________

                                       7