Exhibit 4.19


WARRANT


Series
B


THE SECURITIES REPRESENTED BY THIS WARRANT HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE
STATE SECURITIES LAWS.  THE SECURITIES
HAVE BEEN ACQUIRED FOR INVESTMENT AND MAY NOT BE OFFERED FOR SALE, SOLD,
TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT
FOR THE SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE
STATE SECURITIES LAWS, OR AN OPINION OF COUNSEL IN A FORM REASONABLY SATISFACTORY
TO THE ISSUER THAT REGISTRATION IS NOT REQUIRED UNDER SAID ACT OR APPLICABLE
STATE SECURITIES LAWS OR UNLESS SOLD PURSUANT TO RULE 144 UNDER SAID ACT.


SENESCO TECHNOLOGIES, INC.


Warrant To Purchase Common Stock


	
  Warrant No.: SNT-B-1

  	
   

  	
  Number of Shares:

  	
  1,387,500

  
	
   

  	
   

  	
  Warrant Exercise Price:

  	
  $0.90

  
	
   

  	
   

  	
  Expiration
  Date:            ,
  2012

  



 


Date of Issuance:           ,
2007


Senesco Technologies, Inc., a Delaware corporation
(the “Company”), hereby certifies that, for good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, YA Global Investments, L.P. (the “Holder”),
the registered holder hereof or its permitted assigns, is entitled, subject to
the terms set forth below, to purchase from the Company upon surrender of this
Warrant, at any time or times after the six month anniversary after the date
hereof, but not after 11:59 P.M. Eastern Time on the Expiration Date (as
defined herein) up to 1,387,500 fully paid and nonassessable shares of Common
Stock (as defined herein) of the Company (the “Warrant Shares”) at the
exercise price per share provided in Section 1(b) below or as subsequently
adjusted; provided, however, that in no event shall the holder be entitled to
exercise this Warrant for a number of Warrant Shares in excess of that number
of Warrant Shares which, upon giving effect to such exercise, would cause the
aggregate number of shares of Common Stock beneficially owned by the holder and
its affiliates to exceed 4.99% of the outstanding shares of the Common Stock
following such exercise, except within sixty (60) days of the Expiration Date
(however, such restriction may be waived by Holder (but only as to itself and
not to any other holder) upon not less than 65 days prior notice to the
Company).  For purposes of the foregoing
proviso, the aggregate number of shares of Common Stock beneficially owned by
the holder and its affiliates shall include the number of shares of Common
Stock issuable upon exercise of this Warrant with respect to which the determination
of such proviso is being made, but shall exclude shares of Common Stock which
would be issuable upon (i) exercise of the remaining, unexercised Warrants
beneficially owned by the holder and its affiliates and 













(ii) exercise or conversion of the unexercised or
unconverted portion of any other securities of the Company beneficially owned
by the holder and its affiliates (including, without limitation, any
convertible notes or preferred stock) subject to a limitation on conversion or
exercise analogous to the limitation contained herein.  Except as set forth in the preceding
sentence, for purposes of this paragraph, beneficial ownership shall be
calculated in accordance with Section 13(d) of the Securities Exchange Act of
1934, as amended.  For purposes of this
Warrant, in determining the number of outstanding shares of Common Stock a
holder may rely on the number of outstanding shares of Common Stock as
reflected in (1) the Company’s most recent Form 10-Q or Form 10-K, as the case
may be, (2) a more recent public announcement by the Company or (3) any other
notice by the Company or its transfer agent setting forth the number of shares
of Common Stock outstanding.  Upon the
written request of any holder, the Company shall promptly, but in no event later
than one (1) Business Day following the receipt of such notice, confirm in
writing to any such holder the number of shares of Common Stock then
outstanding.  In any case, the number of
outstanding shares of Common Stock shall be determined after giving effect to
the exercise of Warrants (as defined below) by such holder and its affiliates
since the date as of which such number of outstanding shares of Common Stock
was reported.


Section 1.


(a)          This Warrant is one of
the warrants issued pursuant the Securities Purchase Agreement (“Securities
Purchase Agreement”) dated August 1, 2007 between the Company and the
Buyers listed on Schedule I thereto or issued in exchange or substitution
thereafter or replacement thereof.  Each
Capitalized term used, and not otherwise defined herein, shall have the meaning
ascribed thereto in the Securities Purchase Agreement.


(b)         Definitions.  The following words and terms as used in this
Warrant shall have the following meanings:


(i)                                     “Approved
Stock Plan” means a stock option plan that has been approved by the Board
of Directors of the Company prior to the date of the Securities Purchase
Agreement, pursuant to which the Company’s securities may be issued only to any
employee, officer or director for services provided to the Company.


(ii)                                  
“Business Day” means any day other than Saturday, Sunday or other day on
which commercial banks in the State of New Jersey are authorized or required by
law to remain closed.


(iii)                               “Closing
Bid Price” means the closing bid price of Common Stock as quoted on the
Principal Market (as reported by Bloomberg Financial Markets (“Bloomberg”)
through its “Volume at Price” function).


(iv)                              “Common
Stock” means (i) the Company’s common stock, par value $0.01 per
share, and (ii) any capital stock into which such Common Stock shall have
been changed or any capital stock resulting from a reclassification of such
Common Stock.


(v)                                 “Debenture(s)”
means the convertible debentures issued pursuant to the Securities Purchase
Agreement.



 2
 









(vi)                              “Event
of Default” means an event of default under the Securities Purchase
Agreement or the Convertible Debentures issued in connection therewith.


(vii)                           “Excluded
Securities” means, (a) shares issued or deemed to have been issued by the
Company pursuant to an Approved Stock Plan (b) shares of Common Stock issued or
deemed to be issued by the Company upon the conversion, exchange or exercise of
any right, option, obligation or security outstanding on the date prior to date
of the Securities Purchase Agreement, provided that the terms of such right,
option, obligation or security are not amended or otherwise modified on or
after the date of the Securities Purchase Agreement, and provided that the
conversion price, exchange price, exercise price or other purchase price is not
reduced, adjusted or otherwise modified and the number of shares of Common
Stock issued or issuable is not increased (whether by operation of, or in
accordance with, the relevant governing documents or otherwise) on or after the
date of the Securities Purchase Agreement, (c) shares issued in connection with
any (i) acquisition by the Company, whether through an acquisition of
stock or a merger of any business, assets or technologies, leasing arrangement
or any other transaction the primary purpose of which is not to raise equity
capital, or (ii) license agreement, consulting agreement, strategic
partnership or similar business arrangement, and (d) the shares of Common
Stock issued or deemed to be issued by the Company upon conversion of the
Debenture or the Warrants.


(viii)                        “Expiration
Date” means         , 2012.


(ix)                                “Issuance
Date” means the date hereof.


(x)                                   “Options”
means any rights, warrants or options to subscribe for or purchase Common Stock
or Convertible Securities.


(xi)                                 “Person”
means an individual, a limited liability company, a partnership, a joint
venture, a corporation, a trust, an unincorporated organization and a
government or any department or agency thereof.


(xii)                             “Primary
Market” means on any of (a) the American Stock Exchange, (b) New York Stock
Exchange, (c) the Nasdaq Global Select Market, (d) the Nasdaq Global Market, (e)
the Nasdaq Capital Market, or (e) the NASD Over-the-Counter Bulletin Board (“OTCBB”).


(xiii)                          “Securities
Act” means the Securities Act of 1933, as amended.


(xiv)                         “Warrant”
means this Warrant and all Warrants issued in exchange, transfer or replacement
thereof.


(xv)                            “Warrant
Exercise Price” shall be equal to $0.90, or as subsequently adjusted as
provided in Section 8 hereof.



 3
 









(c)          Other Definitional
Provisions.


(i)                                     Except
as otherwise specified herein, all references herein (A) to the Company
shall be deemed to include the Company’s successors and (B) to any
applicable law defined or referred to herein shall be deemed references to such
applicable law as the same may have been or may be amended or supplemented from
time to time.


(ii)                                  When
used in this Warrant, the words “herein”, “hereof”, and “hereunder” and words of similar import, shall refer to this Warrant
as a whole and not to any provision of this Warrant, and the words “Section”,
“Schedule”, and “Exhibit” shall refer to Sections of, and
Schedules and Exhibits to, this Warrant unless otherwise specified.


(iii)                               Whenever
the context so requires, the neuter gender includes the masculine or feminine,
and the singular number includes the plural, and vice versa.


Section 2.                                            Exercise
of Warrant.


(a)          Subject to the terms and
conditions hereof, this Warrant may be exercised by the holder hereof then
registered on the books of the Company, pro rata as hereinafter provided, at
any time on any Business Day on or after the opening of business on such
Business Day, commencing with the first day after the date hereof, and prior to
11:59 P.M. Eastern Time on the Expiration Date (i) by delivery of a
written notice, in the form of the subscription notice attached as Exhibit A
hereto (the “Exercise Notice”), of such holder’s election to exercise
this Warrant, which notice shall specify the number of Warrant Shares to be
purchased, payment to the Company of an amount equal to the Warrant
Exercise Price(s) applicable to the Warrant Shares being purchased, multiplied
by the number of Warrant Shares (at the applicable Warrant Exercise Price)
as to which this Warrant is being exercised (plus any applicable issue or
transfer taxes) (the “Aggregate Exercise Price”) in cash or wire
transfer of immediately available funds and the surrender of this Warrant (or
an indemnification undertaking with respect to this Warrant in the case of its
loss, theft or destruction) to a common carrier for overnight delivery to the
Company as soon as practicable following such date (“Cash Basis”) or
(ii) if at the time of exercise, the Warrant Shares are not subject to an
effective registration statement, by delivering an Exercise Notice and in lieu
of making payment of the Aggregate Exercise Price in cash or wire transfer,
elect instead to receive upon such exercise the “Net Number” of shares of
Common Stock determined according to the following formula (the “Cashless
Exercise”):


Net Number = (A x B) – (A x C)


B


For purposes of the foregoing formula:


A = the total number of Warrant Shares with respect to which this
Warrant is then being exercised.


B = the Closing Bid Price of the Common Stock on the date of exercise
of the Warrant.



 4
 









C = the Warrant Exercise Price then in effect for the applicable
Warrant Shares at the time of such exercise.


In the event of any exercise of the rights
represented by this Warrant in compliance with this Section 2, the Company
shall on or before the fifth (5th) Business Day following the date of
receipt of the Exercise Notice, the Aggregate Exercise Price and this Warrant
(or an indemnification undertaking with respect to this Warrant in the case of
its loss, theft or destruction) and the receipt of the representations of the
holder specified in Section 6 hereof, if requested by the Company (the “Exercise
Delivery Documents”), and if the Common Stock is DTC eligible, credit such
aggregate number of shares of Common Stock to which the holder shall be
entitled to the holder’s or its designee’s balance account with The Depository
Trust Company; provided, however, if the holder who submitted the Exercise
Notice requested physical delivery of any or all of the Warrant Shares, or, if
the Common Stock is not DTC eligible  then
the Company shall, on or before the fifth (5th) Business Day following
receipt of the Exercise Delivery Documents, issue and surrender to a common
carrier for overnight delivery to the address specified in the Exercise Notice,
a certificate, registered in the name of the holder, for the number of shares
of Common Stock to which the holder shall be entitled pursuant to such
request.  Upon delivery of the Exercise
Notice and Aggregate Exercise Price referred to in clause (i) or (ii)
above, the holder of this Warrant shall be deemed for all corporate purposes to
have become the holder of record of the Warrant Shares with respect to which
this Warrant has been exercised.  In the
case of a dispute as to the determination of the Warrant Exercise Price, the
Closing Bid Price or the arithmetic calculation of the Warrant Shares, the
Company shall promptly issue to the holder the number of Warrant Shares that is
not disputed and shall submit the disputed determinations or arithmetic
calculations to the holder via facsimile within one (1) Business Day of receipt
of the holder’s Exercise Notice.


(b)         If the holder and the
Company are unable to agree upon the determination of the Warrant Exercise
Price or arithmetic calculation of the Warrant Shares within one (1) day of
such disputed determination or arithmetic calculation being submitted to the
holder, then the Company shall immediately submit via facsimile (i) the
disputed determination of the Warrant Exercise Price or the Closing Bid Price
to an independent, reputable investment banking firm or (ii) the disputed
arithmetic calculation of the Warrant Shares to its independent, outside
accountant.  The Company shall cause the
investment banking firm or the accountant, as the case may be, to perform the
determinations or calculations and notify the Company and the holder of the
results no later than forty-eight (48) hours from the time it receives the
disputed determinations or calculations. 
Such investment banking firm’s or accountant’s determination or
calculation, as the case may be, shall be deemed conclusive absent manifest
error.


(c)          Unless the rights
represented by this Warrant shall have expired or shall have been fully
exercised, the Company shall, as soon as practicable and in no event later than
five (5) Business Days after any exercise and at its own expense, issue a new
Warrant identical in all respects to this Warrant exercised except it shall
represent rights to purchase the number of Warrant Shares purchasable
immediately prior to such exercise under this Warrant exercised, less the
number of Warrant Shares with respect to which such Warrant is exercised.



 5
 









(d)         No fractional Warrant
Shares are to be issued upon any pro rata exercise of this Warrant, but rather
the number of Warrant Shares issued upon such exercise of this Warrant shall be
rounded up or down to the nearest whole number.


(e)          RESERVED.


(f)            RESERVED.


Section 3.                                            Covenants
as to Common Stock.  The Company
hereby covenants and agrees as follows:


(a)          This Warrant is, and any
Warrants issued in substitution for or replacement of this Warrant will upon
issuance be, duly authorized and validly issued.


(b)         All Warrant Shares which
may be issued upon the exercise of the rights represented by this Warrant will,
upon issuance, be validly issued, fully paid and nonassessable and free from
all taxes, liens and charges with respect to the issue thereof.


(c)          During the period within
which the rights represented by this Warrant may be exercised, the Company will
at all times have authorized and reserved at least one hundred percent (100%)
of the number of shares of Common Stock needed to provide for the exercise of
the rights then represented by this Warrant and the par value of said shares
will at all times be less than or equal to the applicable Warrant Exercise
Price.  If at any time the Company does not
have a sufficient number of shares of Common Stock authorized and available,
then the Company shall call and hold a special meeting of its stockholders
within sixty (60) days of that time for the sole purpose of increasing the
number of authorized shares of Common Stock.


(d)         If at any time after the
date hereof the Company shall file a registration statement, the Company shall
include the Warrant Shares issuable to the holder, pursuant to the terms of
this Warrant and shall maintain, so long as any other shares of Common Stock
shall be so listed, such listing of all Warrant Shares from time to time
issuable upon the exercise of this Warrant; and the Company shall so list on
each national securities exchange or automated quotation system, as the case
may be, and shall maintain such listing of, any other shares of capital stock
of the Company issuable upon the exercise of this Warrant if and so long as any
shares of the same class shall be listed on such national securities exchange
or automated quotation system.


(e)          The Company will not, by
amendment of its Articles of Incorporation 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 to be observed or performed by it hereunder,
but will at all times in good faith assist in the carrying out of all the
provisions of this Warrant and in the taking of all such action as may
reasonably be requested by the holder of this Warrant in order to protect the
exercise privilege of the holder of this Warrant against dilution or other
impairment, consistent with the tenor and purpose of this Warrant.  The Company will not increase the par value
of any shares of Common Stock receivable upon the exercise of this Warrant
above the Warrant Exercise Price then in effect, and (ii) will take all
such actions as may be necessary or appropriate in order that 



 6
 









the Company may validly and legally issue
fully paid and nonassessable shares of Common Stock upon the exercise of this
Warrant.


(f)            This Warrant will be
binding upon any entity succeeding to the Company by merger, consolidation or
acquisition of all or substantially all of the Company’s assets.


Section 4.                                            Taxes.  The Company shall pay any and all taxes,
except any applicable withholding, which may be payable with respect to the
issuance and delivery of Warrant Shares upon exercise of this Warrant.


Section 5.                                            Warrant
Holder Not Deemed a Stockholder. 
Except as otherwise specifically provided herein, no holder, as such, of
this Warrant shall be entitled to vote or receive dividends or be deemed the
holder of shares of capital stock of the Company for any purpose, nor shall
anything contained in this Warrant be construed to confer upon the holder
hereof, as such, any of the rights of a stockholder of the Company or any right
to vote, give or withhold consent to any corporate action (whether any
reorganization, issue of stock, reclassification of stock, consolidation, merger,
conveyance or otherwise), receive notice of meetings, receive dividends or
subscription rights, or otherwise, prior to the issuance to the holder of this
Warrant of the Warrant Shares which he or she is then entitled to receive upon
the due exercise of this Warrant.  In
addition, nothing contained in this Warrant shall be construed as imposing any
liabilities on such holder to purchase any securities (upon exercise of this
Warrant or otherwise) or as a stockholder of the Company, whether such liabilities
are asserted by the Company or by creditors of the Company.  Notwithstanding this Section 5, the Company
will provide the holder of this Warrant with copies of the same notices and
other information given to the stockholders of the Company generally, contemporaneously
with the giving thereof to the stockholders.


Section 6.                                            Representations
of Holder.  The holder of this
Warrant, by the acceptance hereof, represents that it is acquiring this Warrant
and the Warrant Shares for its own account for investment only and not with a
view towards, or for resale in connection with, the public sale or distribution
of this Warrant or the Warrant Shares, except pursuant to sales registered or
exempted under the Securities Act; provided, however, that by making the representations
herein, the holder does not agree to hold this Warrant or any of the Warrant
Shares for any minimum or other specific term and reserves the right to dispose
of this Warrant and the Warrant Shares at any time in accordance with or
pursuant to a registration statement or an exemption under the Securities
Act.  The holder of this Warrant further
represents, by acceptance hereof, that, as of this date, such holder is an “accredited
investor” as such term is defined in Rule 501(a)(1) of Regulation D
promulgated by the Securities and Exchange Commission under the Securities Act
(an “Accredited Investor”).  Upon
exercise of this Warrant, the holder shall, if requested by the Company,
confirm in writing, in a form satisfactory to the Company, that the Warrant
Shares so purchased are being acquired solely for the holder’s own account and
not as a nominee for any other party, for investment, and not with a view
toward distribution or resale and that such holder is an Accredited
Investor.  If such holder cannot make
such representations because they would be factually incorrect, it shall be a
condition to such holder’s exercise of this Warrant that the Company receive
such other representations as the Company considers reasonably necessary to
assure the Company that the issuance of its securities upon exercise of this
Warrant shall not violate any United States or state securities laws.



 7
 









Section 7.                                            Ownership
and Transfer.


(a)          The Company shall
maintain at its principal executive offices (or such other office or agency of
the Company as it may designate by notice to the holder hereof), a register for
this Warrant, in which the Company shall record the name and address of the
person in whose name this Warrant has been issued, as well as the name and
address of each transferee.  The Company
may treat the person in whose name any Warrant is registered on the register as
the owner and holder thereof for all purposes, notwithstanding any notice to
the contrary, but in all events recognizing any transfers made in accordance
with the terms of this Warrant.


Section 8.                                            Adjustment
of Warrant Exercise Price and Number of Shares.  The Warrant Exercise Price and the number of
shares of Common Stock issuable upon exercise of this Warrant shall be adjusted
from time to time as follows:


(a)          Adjustment of Exercise Price upon
Issuance of Common Stock.  If the Company, at any time while this
Warrant is outstanding, issues
or sells, or in accordance with this Section 8(a) is deemed to have issued or
sold, any shares of Common Stock, excluding shares of Common Stock deemed to
have been issued or sold by the Company in connection with any Excluded
Securities, for a consideration per share less than a price equal to the Exercise
Price in effect immediately prior to such issue or sale (such price the “Applicable
Price”) (the
foregoing a “Dilutive Issuance”), then immediately after such
Dilutive Issuance the Exercise Price then in effect shall be reduced to an
amount equal to the product of (A) the Exercise Price in effect immediately
prior to such Dilutive Issuance and (B) the quotient determined by dividing (1)
the sum of (I) the product derived by multiplying the Exercise Price in effect
immediately prior to such Dilutive Issuance and the number of shares of Common
Stock Deemed Outstanding immediately prior to such Dilutive Issuance plus (II)
the consideration, if any, received by the Company upon such Dilutive Issuance,
by (2) the product derived by multiplying (I) the Exercise Price in effect
immediately prior to such Dilutive Issuance by (II) the number of shares of
Common Stock deemed outstanding immediately after such Dilutive Issuance.


(b)         Effect on Warrant
Exercise Price of Certain Events. 
For purposes of determining the adjusted Warrant Exercise Price under
Section 8(a) above, the following shall be applicable:


(i)                                     Issuance
of Options.  If after the date
hereof, the Company in any manner grants any Options and the lowest price per
share for which one share of Common Stock is issuable upon the exercise of any
such Option or upon conversion or exchange of any convertible securities
issuable upon exercise of any such Option is less than the Applicable Price,
then such share of Common Stock shall be deemed to be outstanding and to have
been issued and sold by the Company at the time of the granting or sale of such
Option for such price per share.  For
purposes of this Section 8(b)(i), the lowest price per share for which one
share of Common Stock is issuable upon exercise of such Options or upon conversion
or exchange of such Convertible Securities shall be equal to the sum of the
lowest amounts of consideration (if any) received or receivable by the Company
with respect to any one share of Common Stock upon the granting or sale of the
Option, upon exercise of the Option or upon conversion or exchange of any
convertible security issuable upon exercise of such Option.  No further adjustment of the Warrant Exercise
Price shall be made upon the actual issuance of such 



 8
 









Common Stock or of such convertible
securities upon the exercise of such Options or upon the actual issuance of
such Common Stock upon conversion or exchange of such convertible securities.


(ii)                                  Issuance
of Convertible Securities.  If the
Company in any manner issues or sells any convertible securities and the lowest
price per share for which one share of Common Stock is issuable upon the
conversion or exchange thereof is less than the Applicable Price, then such
share of Common Stock shall be deemed to be outstanding and to have been issued
and sold by the Company at the time of the issuance or sale of such convertible
securities for such price per share.  For
the purposes of this Section 8(b)(ii), the lowest price per share for
which one share of Common Stock is issuable upon such conversion or exchange
shall be equal to the sum of the lowest amounts of consideration (if any)
received or receivable by the Company with respect to one share of Common Stock
upon the issuance or sale of the convertible security and upon conversion or
exchange of such convertible security. 
No further adjustment of the Warrant Exercise Price shall be made upon
the actual issuance of such Common Stock upon conversion or exchange of such
convertible securities, and if any such issue or sale of such convertible
securities is made upon exercise of any Options for which adjustment of the
Warrant Exercise Price had been or are to be made pursuant to other provisions
of this Section 8(b), no further adjustment of the Warrant Exercise Price shall
be made by reason of such issue or sale.


(iii)                               Change
in Option Price or Rate of Conversion. 
If the purchase price provided for in any Options, the additional
consideration, if any, payable upon the issue, conversion or exchange of any
convertible securities, or the rate at which any convertible securities are
convertible into or exchangeable for Common Stock changes at any time, the
Warrant Exercise Price in effect at the time of such change shall be adjusted
to the Warrant Exercise Price which would have been in effect at such time had
such Options or convertible securities provided for such changed purchase
price, additional consideration or changed conversion rate, as the case may be,
at the time initially granted, issued or sold and the number of Warrant Shares
issuable upon exercise of this Warrant shall be correspondingly
readjusted.  For purposes of this Section
8(b)(iii), if the terms of any Option or convertible security that was
outstanding as of the Issuance Date of this Warrant are changed in the manner
described in the immediately preceding sentence, then such Option or
convertible security and the Common Stock deemed issuable upon exercise,
conversion or exchange thereof shall be deemed to have been issued as of the
date of such change.  No adjustment
pursuant to this Section 8(b) shall be made if such adjustment would
result in an increase of the Warrant Exercise Price then in effect.


(iv)                              Calculation
of Consideration Received.  If any
Common Stock, Options or convertible securities are issued or sold or deemed to
have been issued or sold for cash, the consideration received therefore will be
deemed to be the net amount received by the Company therefore.  If any Common Stock, Options or convertible
securities are issued or sold for a consideration other than cash, the amount
of such consideration received by the Company will be the fair value of such
consideration, except where such consideration consists of marketable
securities, in which case the amount of consideration received by the Company
will be the market price of such securities on the date of receipt of such
securities.  If any Common Stock, Options
or convertible securities are issued to the owners of the non-surviving entity
in connection with any merger in which the Company is the surviving entity, the
amount of 



 9















consideration therefore will be deemed to be
the fair value of such portion of the net assets and business of the
non-surviving entity as is attributable to such Common Stock, Options or
convertible securities, as the case may be. 
The fair value of any consideration other than cash or securities will
be determined jointly by the Company and the holders of Warrants representing
at least two-thirds of the Warrant Shares issuable upon exercise of the
Warrants then outstanding.  If such
parties are unable to reach agreement within ten (10) days after the
occurrence of an event requiring valuation (the “Valuation Event”), the
fair value of such consideration will be determined within five (5) Business
Days after the tenth (10th) day following the Valuation Event by an
independent, reputable appraiser jointly selected by the Company and the
holders of Warrants representing at least two-thirds of the Warrant Shares
issuable upon exercise of the Warrants then outstanding.  The determination of such appraiser shall be
final and binding upon all parties and the fees and expenses of such appraiser
shall be borne jointly by the Company and the holders of Warrants.


(v)                                 Integrated
Transactions.  In case any Option is
issued in connection with the issue or sale of other securities of the Company,
together comprising one integrated transaction in which no specific
consideration is allocated to such Options by the parties thereto, the Options
will be deemed to have been issued for a consideration of $.01.


(vi)                              Treasury
Shares.  The number of shares of
Common Stock outstanding at any given time does not include shares owned or
held by or for the account of the Company, and the disposition of any shares so
owned or held will be considered an issue or sale of Common Stock.


(vii)                           Record
Date.  If the Company takes a record
of the holders of Common Stock for the purpose of entitling them (1) to
receive a dividend or other distribution payable in Common Stock, Options or in
convertible securities or (2) to subscribe for or purchase Common Stock,
Options or convertible securities, then such record date will be deemed to be
the date of the issue or sale of the shares of Common Stock deemed to have been
issued or sold upon the declaration of such dividend or the making of such
other distribution or the date of the granting of such right of subscription or
purchase, as the case may be.


(viii)                        Primary
Market Regulation.  The Company shall
not be obligated to issue any shares of Common Stock upon exercise of this
Warrant, and the Holder of this Warrant shall not have the right to receive
upon exercise of this Warrant any shares of Common Stock, if the issuance of
such shares of Common Stock would exceed the aggregate number of shares of
Common Stock which the Company may issue upon conversion or exercise, as
applicable, of the Debentures and Warrants, including the securities issued by
the Company in connection with the Stanford Closing (as defined in the
Securities Purchase Agreement), without breaching the Company’s obligations
under the rules or regulations of the (a) the American Stock Exchange, (b) New
York Stock Exchange, (c) the Nasdaq Global Market, (d) the Nasdaq Capital
Market, or (e) the NASD OTC Bulletin Board (“OTCBB”) (each, a “Primary
Market”) (the number of shares which may be issued without violating such
rules and regulations, the “Exchange
Cap”), except that such
limitation shall not apply in the event that the Company (A) obtains the
approval of its stockholders as required by the applicable rules of such
Primary Market for issuances of Common Stock in excess of such amount or (B)
obtains a written opinion from outside counsel to the Company that such
approval is not required, which opinion 



 10
 









shall be reasonably satisfactory to the
Holder.  Unless and until such approval
or written opinion is obtained, the purchaser of the Warrant pursuant to the
Securities Purchase Agreement (or any subsequent holder) shall not be issued in
the aggregate, upon conversion or exercise or otherwise, as applicable, of
Debenture or Warrants, shares of Common Stock in an amount greater than the
Exchange Cap.  In addition to the
foregoing, the Share Cap (as defined in the Debentures) shall also apply to
this Warrant.


(c)          Adjustment of Warrant
Exercise Price upon Subdivision or Combination of Common Stock.  If the Company at any time after the date of
issuance of this Warrant subdivides (by any stock split, stock dividend,
recapitalization or otherwise) one or more classes of its outstanding shares of
Common Stock into a greater number of shares, any Warrant Exercise Price in
effect immediately prior to such subdivision will be proportionately reduced
and the number of shares of Common Stock obtainable upon exercise of this
Warrant will be proportionately increased. 
If the Company at any time after the date of issuance of this Warrant
combines (by combination, reverse stock split or otherwise) one or more classes
of its outstanding shares of Common Stock into a smaller number of shares, any
Warrant Exercise Price in effect immediately prior to such combination will be
proportionately increased and the number of Warrant Shares issuable upon
exercise of this Warrant will be proportionately decreased.  Any adjustment under this Section 8(c)
shall become effective at the close of business on the date the subdivision or
combination becomes effective.


(d)         Distribution of Assets.  If the Company shall declare or make any
dividend or other distribution of its assets (or rights to acquire its assets)
to holders of Common Stock, by way of return of capital or otherwise
(including, without limitation, any distribution of cash, stock or other
securities, property or options by way of a dividend, spin off,
reclassification, corporate rearrangement or other similar transaction) (a “Distribution”),
at any time after the issuance of this Warrant, then, in each such case:


(i)                                     any
Warrant Exercise Price in effect immediately prior to the close of business on
the record date fixed for the determination of holders of Common Stock entitled
to receive the Distribution shall be reduced, effective as of the close of
business on such record date, to a price determined by multiplying such Warrant
Exercise Price by a fraction of which (A) the numerator shall be the Closing
Sale Price of the Common Stock on the trading day immediately preceding such
record date minus the value of the Distribution (as determined in good faith by
the Company’s Board of Directors) applicable to one share of Common Stock, and
(B) the denominator shall be the Closing Sale Price of the Common Stock on the
trading day immediately preceding such record date; and


(ii)                                  either
(A) the number of Warrant Shares obtainable upon exercise of this Warrant shall
be increased to a number of shares equal to the number of shares of Common
Stock obtainable immediately prior to the close of business on the record date
fixed for the determination of holders of Common Stock entitled to receive the
Distribution multiplied by the reciprocal of the fraction set forth in the
immediately preceding clause (i), or (B) in the event that the Distribution is
of common stock of a company whose common stock is traded on a national
securities exchange or a national automated quotation system, then the holder
of this Warrant shall receive an additional warrant to purchase Common Stock,
the terms of which shall be identical to those of this Warrant, except that
such warrant shall be exercisable into the 



 11
 









amount of the assets that would have been
payable to the holder of this Warrant pursuant to the Distribution had the
holder exercised this Warrant immediately prior to such record date and with an
exercise price equal to the amount by which the exercise price of this Warrant
was decreased with respect to the Distribution pursuant to the terms of the
immediately preceding clause (i).


(e)          Certain Events.  If any event occurs of the type contemplated
by the provisions of this Section 8 but not expressly provided for by such
provisions (including, without limitation, the granting of stock appreciation
rights, phantom stock rights or other rights with equity features), then the
Company’s Board of Directors will make an appropriate adjustment in the Warrant
Exercise Price and the number of shares of Common Stock obtainable upon
exercise of this Warrant so as to protect the rights of the holders of the Warrants;
provided, except as set forth in section 8(c),that no such adjustment pursuant
to this Section 8(e) will increase the Warrant Exercise Price or decrease the
number of shares of Common Stock obtainable as otherwise determined pursuant to
this Section 8.


(f)            Voluntary
Adjustments By Company.  The Company
may at any time during the term of this Warrant reduce the then current
Exercise Price to any amount and for any period of time deemed appropriate by
the Board of Directors of the Company.


(g)         Notices.


(i)                                     Immediately
upon any adjustment of the Warrant Exercise Price, the Company will give
written notice thereof to the holder of this Warrant, setting forth in
reasonable detail, and certifying, the calculation of such adjustment.


(ii)                                  The
Company will give written notice to the holder of this Warrant at least ten
(10) days prior to the date on which the Company closes its books or takes a
record (A) with respect to any dividend or distribution upon the Common
Stock, (B) with respect to any pro rata subscription offer to holders of
Common Stock or (C) for determining rights to vote with respect to any
Organic Change (as defined below), dissolution or liquidation, provided that
such information shall be made known to the public prior to or in conjunction
with such notice being provided to such holder.


(iii)                               The
Company will also give written notice to the holder of this Warrant at least
ten (10) days prior to the date on which any Organic Change, dissolution or
liquidation will take place, provided that such information shall be made known
to the public prior to or in conjunction with such notice being provided to
such holder.


Section 9.                                            Purchase
Rights; Reorganization, Reclassification, Consolidation, Merger or Sale.


(a)          In addition to any
adjustments pursuant to Section 8 above, if at any time the Company grants,
issues or sells any Options, Convertible Securities or rights to purchase
stock, warrants, securities or other property pro rata to the record holders of
any class of Common Stock (the “Purchase Rights”), then the holder of
this Warrant will be entitled to acquire, upon the terms applicable to such
Purchase Rights, the aggregate Purchase Rights which such holder could have
acquired if such holder had held the number of shares of Common Stock
acquirable 



 12
 









upon complete exercise of this Warrant
immediately before the date on which a record is taken for the grant, issuance
or sale of such Purchase Rights, or, if no such record is taken, the date as of
which the record holders of Common Stock are to be determined for the grant,
issue or sale of such Purchase Rights.


(b)         Any recapitalization,
reorganization, reclassification, consolidation, merger, sale of all or
substantially all of the Company’s assets to another Person or other
transaction in each case which is effected in such a way that holders of Common
Stock are entitled to receive (either directly or upon subsequent liquidation)
stock, securities or assets with respect to or in exchange for Common Stock is
referred to herein as an “Organic Change.”  Prior to the consummation of any (i) sale of
all or substantially all of the Company’s assets to an acquiring Person or (ii)
other Organic Change following which the Company is not a surviving entity, the
Company will secure from the Person purchasing such assets or the successor
resulting from such Organic Change (in each case, the “Acquiring Entity”)
a written agreement (in form and substance satisfactory to the holders of
Warrants representing at least two-thirds (iii) of the Warrant Shares
issuable upon exercise of the Warrants then outstanding) to deliver to each
holder of Warrants in exchange for such Warrants, a security of the Acquiring
Entity evidenced by a written instrument substantially similar in form and
substance to this Warrant and satisfactory to the holders of the Warrants
(including an adjusted warrant exercise price equal to the value for the Common
Stock reflected by the terms of such consolidation, merger or sale, and
exercisable for a corresponding number of shares of Common Stock acquirable and
receivable upon exercise of the Warrants without regard to any limitations on
exercise, if the value so reflected is less than any Applicable Warrant
Exercise Price immediately prior to such consolidation, merger or sale).  Prior to the consummation of any other
Organic Change, the Company shall make appropriate provision (in form and
substance satisfactory to the holders of Warrants representing a majority  of the Warrant Shares issuable upon exercise of the
Warrants then outstanding) to insure that each of the holders of the Warrants
will thereafter have the right to acquire and receive in lieu of or in addition
to (as the case may be) the Warrant Shares immediately theretofore issuable and
receivable upon the exercise of such holder’s Warrants (without regard to
any limitations on exercise), such shares of stock, securities or assets that
would have been issued or payable in such Organic Change with respect to or in
exchange for the number of Warrant Shares which would have been issuable and
receivable upon the exercise of such holder’s Warrant as of the date of such
Organic Change (without taking into account any limitations or restrictions on
the exercisability of this Warrant).


Section 10.                                      Lost, Stolen,
Mutilated or Destroyed Warrant.  If
this Warrant is lost, stolen, mutilated or destroyed, the Company shall
promptly, on receipt of an indemnification undertaking (or, in the case of a
mutilated Warrant, the Warrant), issue a new Warrant of like denomination and
tenor as this Warrant so lost, stolen, mutilated or destroyed.


Section 11.                                      Notice.  Any notices, consents, waivers or other
communications required or permitted to be given under the terms of this
Warrant must be in writing and will be deemed to have been delivered:  (i) upon receipt, when delivered
personally; (ii) upon receipt, when sent by facsimile (provided
confirmation of receipt is received by the sending party transmission is
mechanically or electronically generated and kept on file by the sending
party); or (iii) one Business Day after deposit with a nationally
recognized overnight delivery service, in each case 



 13
 









properly addressed to the party to receive the same.  The addresses and facsimile numbers for such
communications shall be:


	
  If to Holder:

  	
  YA Global Investments, LP

  
	
   

  	
  101 Hudson Street – Suite 3700

  
	
   

  	
  Jersey City, NJ 07302

  
	
   

  	
  Attention:

  	
  Mark A. Angelo

  
	
   

  	
  Telephone:

  	
  (201) 985-8300

  
	
   

  	
  Facsimile:

  	
  (201) 985-8266

  
	
   

  	
   

  
	
  With Copy to:

  	
  David Gonzalez, Esq.

  
	
   

  	
  101 Hudson Street – Suite 3700

  
	
   

  	
  Jersey City, NJ 07302

  
	
   

  	
  Telephone:

  	
  (201) 985-8300

  
	
   

  	
  Facsimile:

  	
  (201) 985-8266

  
	
   

  	
   

  
	
   

  	
   

  
	
  If to the
  Company, to:

  	
  Senesco Technologies, Inc.

  
	
   

  	
  303 George Street, Suite 420

  
	
   

  	
  New Brunswick, NJ 08901

  
	
   

  	
  Attention:

  	
  Chief Executive Officer

  
	
   

  	
  Telephone:

  	
  (732) 296-8400

  
	
   

  	
  Facsimile:

  	
  (732) 296-9292

  
	
   

  	
   

  
	
  With a copy to:

  	
  Morgan, Lewis & Bockius LLP

  
	
   

  	
  502 Carnegie Center

  
	
   

  	
  Princeton, NJ 08540

  
	
   

  	
  Attention:

  	
  Emilio Ragosa, Esq.

  
	
   

  	
  Telephone:

  	
  (609) 919-6633

  
	
   

  	
  Facsimile:

  	
  (609) 919-6701

  



 


If to a holder of this Warrant, to it at the address
and facsimile number set forth in this Section 11, or at such other address and
facsimile as shall be delivered to the Company upon the issuance or transfer of
this Warrant.  Each party shall provide
five days’ prior written notice to the other party of any change in address or
facsimile number.  Written confirmation
of receipt (A) given by the recipient of such notice, consent, facsimile,
waiver or other communication, (or (B) provided by a nationally recognized
overnight delivery service shall be rebuttable evidence of personal service,
receipt by facsimile or receipt from a nationally recognized overnight delivery
service in accordance with clause (i), (ii) or (iii) above, respectively.


Section 12.                                      Date.  The date of this Warrant is set forth on page
1 hereof.  This Warrant, in all
events, shall be wholly void and of no effect after the close of business on
the Expiration Date.



 14
 









Section 13.                                      Amendment and
Waiver.  Except as otherwise provided
herein, the provisions of the Warrants may be amended and the Company may take
any action herein prohibited, or omit to perform any act herein required to be
performed by it, only if the Company has obtained the written consent of the
holders of Warrants representing at least two-thirds of the Warrant Shares
issuable upon exercise of the Warrants then outstanding; provided that, except
for Section 8(d), no such action may increase the Warrant Exercise Price or
decrease the number of shares or class of stock obtainable upon exercise of any
Warrant without the written consent of the holder of such Warrant.


Section 14.                                      Descriptive
Headings; Governing Law.  The
descriptive headings of the several sections and paragraphs of this Warrant are
inserted for convenience only and do not constitute a part of this
Warrant.  The corporate laws of the State
of Delaware shall govern all issues concerning the relative rights of the
Company and its stockholders.  All other
questions concerning the construction, validity, enforcement and interpretation
of this Agreement shall be governed by the internal laws of the State of New
Jersey, without giving effect to any choice of law or conflict of law provision
or rule (whether of the State of New Jersey or any other jurisdictions) that
would cause the application of the laws of any jurisdictions other than the State
of New Jersey.  Each party hereby
irrevocably submits to the exclusive jurisdiction of the state and federal
courts sitting in Hudson County and the United States District Court for the
District of New Jersey, for the adjudication of any dispute hereunder or in
connection herewith or therewith, or with any transaction contemplated hereby
or discussed herein, and hereby irrevocably waives, and agrees not to assert in
any suit, action or proceeding, any claim that it is not personally subject to
the jurisdiction of any such court, that such suit, action or proceeding is
brought in an inconvenient forum or that the venue of 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 to such
party at the address for such notices to it under this Agreement 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.


Section 15.                                   Waiver
of Jury Trial.  AS A
MATERIAL INDUCEMENT FOR EACH PARTY HERETO TO ENTER INTO THIS WARRANT, THE
PARTIES HERETO HEREBY WAIVE ANY RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING
RELATED IN ANY WAY TO THIS WARRANT AND/OR ANY AND ALL OF THE OTHER DOCUMENTS
ASSOCIATED WITH THIS TRANSACTION.


Section 16.Accounting Provision.  For purposes of clarity, the Company shall
not be obligated to settle any exercise of this Warrant in cash, except as a
result of the negligence or willful misconduct of the Company, then in such
case, any cash settlement shall be as per the terms of this Warrant.


REMAINDER
OF PAGE INTENTIONALLY LEFT BLANK



 15
 









IN WITNESS WHEREOF,
the Company has caused this Warrant to be signed as of the date first set forth
above.


	
  

  	
   

  	
  SENESCO TECHNOLOGIES, INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
  Name:

  
	
   

  	
   

  	
  Title:

  



 



 16














EXHIBIT
A TO WARRANT


EXERCISE
NOTICE


TO BE EXECUTED 

BY THE REGISTERED HOLDER TO EXERCISE THIS WARRANT


SENESCO TECHNOLOGIES, INC.


The undersigned holder hereby exercises the right to
purchase                             
of the shares of Common Stock (“Warrant Shares”) of Senesco
Technologies, Inc. (the “Company”), evidenced by the attached Warrant
(the “Warrant”).  Capitalized
terms used herein and not otherwise defined shall have the respective meanings
set forth in the Warrant.


Specify Method of exercise by check mark:


1.                       Cash Exercise


(a) Payment of Warrant
Exercise Price. The holder shall pay the Aggregate Exercise Price of $                            
to the Company in accordance with the terms of the Warrant.


(b) Delivery of
Warrant Shares.  The Company shall
deliver to the holder                   
Warrant Shares in accordance with the terms of the Warrant.


2.                       Cashless Exercise


(a) Payment of Warrant
Exercise Price.  In lieu of making
payment of the Aggregate Exercise Price, the holder elects to receive upon such
exercise the Net Number of shares of Common Stock determined in accordance with
the terms of the Warrant.


(b) Delivery of
Warrant Shares.  The Company shall
deliver to the holder                   
Warrant Shares in accordance with the terms of the Warrant.


Date:                               
    ,             


	
  Name of Registered Holder

  
	
   

  
	
  By:

  	
   

  	
   

  
	
  Name:

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  
					



 

















EXHIBIT
B TO WARRANT


FORM
OF WARRANT POWER


FOR VALUE RECEIVED,
the undersigned does hereby assign and transfer to                                 ,
Federal Identification No.                     ,
a warrant to purchase                         
shares of the capital stock of Senesco Technologies, Inc. represented by
warrant certificate no.           ,
standing in the name of the undersigned on the books of said corporation.  The undersigned does hereby irrevocably
constitute and appoint                             ,
attorney to transfer the warrants of said corporation, with full power of
substitution in the premises.


	
  Dated:

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
   

  
	
   

  	
   

  	
  Name:

  	
   

  
	
   

  	
   

  	
  Title:

  	
   

  
								



 



 B-1