AMENDED
      CERTIFICATE OF INCORPORATION





OF





SYMBOLLON
      PHARMACEUTICALS, INC.





FIRST:  The
      name
      of the corporation is SYMBOLLON PHARMACEUTICALS, INC. (hereinafter referred
      to
      as the "Corporation").





SECOND:  The
      address of the Corporation's registered office in the State of Delaware is
      32
      Loockerman Square, Suite L-100, City of Dover, County of Kent, 19901. The name
      of the registered agent at such address is The Prentice-Hall Corporation System,
      Inc.





THIRD:  The
      purpose of the Corporation is to engage in any lawful act or activity for which
      corporations may be organized under the Delaware General Corporation
      Law.





FOURTH:  I.
      The
      aggregate number of shares which the Corporation shall have authority to issue
      is One Hundred Million (100,000,000) shares, consisting of (i) Ninety-Three
      Million Seven Hundred Fifty Thousand (93,750,000) shares of Class A Common
      Stock, par value $.001 per share ("Class A Common Stock"), (ii) One Million
      Two
      Hundred Fifty Thousand (1,250,000) shares of Class B Common Stock, par value
      $.001 per share ("Class B Common Stock"), and (iii) Five Million (5,000,000)
      shares of Preferred Stock, par value $.001 per share ("Preferred
      Stock").





II.
      Except as otherwise provided in this Article FOURTH, the rights, preferences
      and
      limitations of Class A Common Stock and Class B Common Stock shall be identical
      in all respects:





(a)
      The
      dividend rights of the holders of shares of Class A Common Stock and Class
      B
      Common Stock shall be identical, except that no stock dividends on the Class
      A
      Common Stock may be paid in Class B Common Stock and no stock dividends on
      the
      Class B Common Stock may be paid in Class A Common Stock. Whenever a stock
      dividend is paid, the holder of a share of any class of common stock shall
      be
      paid in the same number of shares of common stock of the class of such shares
      as
      are paid to the holder of a share of common stock of any other class in shares
      of common stock of such other class. Whenever a combination or subdivision
      of
      the shares of any class of common stock is made, the same combination or
      subdivision shall be made with respect to the other classes of common
      stock.





(b)
      Each
      share of Class A Common Stock shall entitle the holder to one vote and each
      share of Class B Common Stock shall entitle the holder to five votes on all
      matters with respect to which holders of such classes of stock are entitled
      to
      vote.










(c)  (i)
      All
      outstanding shares of Class B Common Stock shall be convertible at all times,
      at
      the election of the holder thereof, into an equal number of fully paid and
      nonassessable shares of Class A Common Stock by delivery of written notice
      by
      the holder of such shares of Class B Common Stock to the Corporation, or its
      transfer agent, of his election together with the certificate(s) representing
      the shares to be converted. Thereupon, the Corporation, or its transfer agent,
      as the case may be, shall exchange such certificate(s) for a certificate or
      certificates representing an equal number of shares of Class A Common Stock.
      Shares of Class B Common Stock shall be deemed to have been converted
      immediately prior to the close of business on the day upon which the
      Corporation, or its transfer agent, receives such shares for conversion. The
      person entitled to receive the Class A Common Stock issuable upon such
      conversion shall be treated for all purposes as the record holder of such Class
      A Common Stock at such time.





(ii)
      Except as provided in subparagraph (iii) below, upon the sale, assignment,
      transfer, conveyance, or other disposition, whether voluntary, by operation
      of
      law or otherwise (a "Transfer", which, for the purpose hereof, shall not include
      a pledge) of shares of Class B Common Stock, other than a transfer to another
      holder of Class B Common Stock or to a private charitable foundation as to
      which
      a holder of Class B Common Stock is the sole voting member, the shares so
      transferred shall, by virtue of such Transfer, automatically be converted into
      an equal number of fully paid and nonassessable shares of Class A Common
      Stock.





(iii)
      Upon the death of any holder of Class B Common Stock, the shares of Class B
      Common Stock so held as of the date of death of the deceased stockholder shall
      be automatically converted into an equal number of fully paid and nonassessable
      shares of Class A Common Stock unless and to the extent that any of such shares
      are purchased by another holder of Class B Common Stock on or prior to 90 days
      from the date that a legal representative is duly appointed by a court of
      competent jurisdiction, or 120 days from such date if within such 90 day period
      another holder of Class B Common Stock has exercised any right to purchase
      shares of Class B Common Stock held by such legal representative. If there
      should be only one holder of Class B Common Stock, effective immediately upon
      his death, the shares of Class B Common Stock so held as of the date of death
      shall be automatically converted into an equal number of fully paid and
      nonassessable shares of Class A Common Stock.





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(iv)
      With
      respect to any shares of Class B Common Stock converted into Class A Common
      Stock pursuant to paragraphs (i), (ii) and (iii) above, until surrender as
      hereinafter provided, each outstanding certificate, which prior to such
      conversion represented shares of Class B Common Stock, shall be deemed for
      all
      purposes to evidence ownership of the number of shares of Class A Common Stock
      into which the shares of Class B Common Stock shall have been converted. Upon
      surrender to the Corporation, or its transfer agent, for cancellation of the
      certificate or certificates representing such shares, the holder thereof shall
      be entitled to receive a certificate or certificates representing the number
      of
      shares of Common Stock to which such holder is entitled.





(v)
      With
      respect to any shares of Class B Common Stock converted into Class A Common
      Stock pursuant to paragraphs (i), (ii) or (iii) above, such converted shares
      of
      Class B Common Stock shall, from and after the date of conversion, have the
      status of authorized and unissued shares of Class B Common Stock and may be
      reissued as shares of Class B Common Stock.





III.
      The
      Board of Directors of the Corporation is authorized, subject to limitations
      prescribed by law and the provisions of this Article FOURTH, to provide for,
      from time to time, in one or more series of any number, the issuance of shares
      of Preferred Stock, and, by filing a certificate pursuant to the General
      Corporation Law of the State of Delaware, to establish the number of shares
      to
      be included in each such series and to fix the designation, relative rights,
      preferences, qualifications and limitations of the shares of each such series.
      The authority of the Board Directors with respect to each series shall include,
      but not be limited to, determination of each of the following:





A.
      The
      number of shares constituting that series and the distinctive designation of
      that series;





B.
      The
      dividend rate on the shares of the series, whether dividends shall be cumulative
      and, if so, from which date or dates, and whether they shall be payable in
      preference to, or in another relation to, the dividends payable on any other
      class or classes or series of stock;





C.
      Whether that series shall have voting rights, in addition to the voting rights
      provided by law, and, if so, the terms of such voting rights;





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D.
      Whether that series shall have conversion or exchange privileges, and, if so,
      the terms and conditions of such conversion or exchange, including provision
      for
      adjustment of the conversion or exchange rate in such events as the Board of
      Directors shall determine;





E.
      Whether or not the shares of that series shall be redeemable, and if so, the
      terms and conditions of such redemption, including the manner of selecting
      shares for redemption if less than all such shares are to be redeemed, the
      date
      or dates upon or after which they shall be redeemable, and the amount per share
      payable in case of redemption, which amount may vary under different conditions
      and at different redemption dates;





F.
      Whether that series shall be entitled to the benefit of a sinking fund to be
      applied to the purchase or redemption of shares of that series and, if so,
      the
      terms and amounts of such sinking fund;





G.
      The
      right of the shares of the series to the benefit of conditions and restrictions
      upon the creation of indebtedness of the Corporation or any subsidiary, upon
      the
      issue of any additional stock (including additional shares of such series or
      of
      any other series) and upon the payment of dividends or the making of other
      distributions on and the purchase, redemption or other acquisition by the
      Corporation or any subsidiary of, any outstanding stock of the
      Corporation;





H.
      The
      right of the shares of that series in the event of any voluntary or involuntary
      liquidation, dissolution or winding up of the Corporation, and whether such
      rights shall be in preference to or in another relation to the comparable rights
      of any other class or classes or series of stock; and





I.
      Any
      other relative, participating optional or other special, rights, qualifications,
      limitations or restrictions of that series.





IV.
      Shares of any series of Preferred Stock which have been redeemed (whether
      through the operation of a sinking fund or otherwise) or which, if convertible
      or exchangeable, have been converted into or exchanged for shares of stock
      of
      any other class or classes, shall have the status of authorized and unissued
      shares of Preferred Stock of the same series and may be reissued as part of
      the
      series of which they were originally a part or may be reclassified and reissued
      as part of any other series of Preferred Stock or of a new series of Preferred
      Stock to be created by resolution or resolutions of the Board of Directors,
      all
      subject to the conditions and the restrictions on issuance set forth in the
      resolution or resolutions adopted by the Board of Directors providing for the
      issue of any series of Preferred Stock.





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V.
      Except
      as otherwise provided by the resolution or resolutions providing for the issue
      of any series of Preferred Stock, after payment shall have been made to the
      holders of Preferred Stock of the full amount of dividends to which they shall
      be entitled pursuant to the resolution or resolutions providing for the issuance
      of any series of preferred Stock, the holders of Class A and Class B Common
      Stock shall be entitled, to the exclusion of the holders of Preferred Stock
      of
      any and all series, to receive such dividends as from time to time may be
      declared by the Board of Directors.





VI.
      Except as otherwise provided by the resolution or resolutions providing for
      the
      issue of any series of Preferred Stock, in the event of any liquidation,
      dissolution of winding up of the Corporation, whether voluntary or involuntary,
      the holders of Class A and Class B Common Stock shall be entitled, after payment
      shall have been made to the holders of Preferred Stock of the full amount to
      which they shall be entitled pursuant to the resolution or resolutions providing
      for the issuance of any series of Preferred Stock, to share, to the exclusion
      of
      the holders of Preferred Stock of any and all series, in all remaining assets
      of
      the Corporation available for distribution to its stockholders ratably according
      to the number of shares of Class A and Class B Common Stock held by
      them.





VII.
      The
      number of authorized shares of any class may be increased or decreased by the
      affirmative vote of the holders of a majority of the stock of the Corporation
      entitled to vote.





FIFTH:
      The name and mailing address of the sole incorporator are as


follows:





Veronica
      Andrews Goldberg


Rubin
      Baum Levin Constant & Friedman


30
      Rockfeller Plaza, 29th Floor


New
      York
      New York 11012





SIXTH:





I.
      Number
      of Directors. The number of directors of the Corporation shall not be less
      than
      three. The exact number of directors within the limitations specified in the
      preceding sentence shall be fixed from time to time by the Board of
      Directors.





II.
      Classes of Directors. The Board of Directors shall be and is divided into three
      classes: Class I, Class II and Class III. No one class shall have more than
      one
      director more than any other class. If a fraction is contained in the quotient
      arrived at by dividing the designated number of directors by three, then, if
      such fraction is one-third, the extra director shall be a member of Class I,
      and
      if such fraction is two-thirds, one of the extra directors shall be a member
      of
      Class I and one of the extra directors shall be a member of Class II, unless
      otherwise provided from time to time by resolution adopted by the Board of
      Directors.





III.
      Terms of Office. Each director shall serve for a term ending on the date of
      the
      third annual meeting following the annual meeting at


which
      such director was elected; provided, that each initial director in Class I
      shall
      serve for a term ending on the date of the annual meeting in 2000; each initial
      director in Class II shall serve for a term ending on the date of the annual
      meeting in 2001; and each initial director in Class III shall serve for a term
      ending on the date of the annual meeting in 2002; and provided further, that
      the
      term of each director shall be subject to the election and qualification of
      his
      successor and to his earlier death, resignation or removal.





IV.
      Allocation of Directors Among Classes in the Event of Increases or Decreases
      in
      the Number of Directors. In the event of any increase or decrease in the
      authorized number of directors, (i) each director then serving as such shall
      nevertheless continue as a director of the class of which he is a member for
      the
      full term of such class and (ii) the newly created or eliminated directorships
      resulting from such increase or decrease shall be apportioned by the Board
      of
      Directors among the three classes of directors so as to ensure that no one
      class
      has more than one director more than any other class. To the extent possible,
      consistent with the foregoing rule, any newly created directorships shall be
      added to those classes whose terms of office are to expire at the latest dates
      following such allocation, and any newly eliminated directorships shall be
      subtracted from those classes whose terms of offices are to expire at the
      earliest dates following such allocation, unless otherwise provided from time
      to
      time by resolution adopted by the Board of Directors.





V.
      Quorum; Action at Meeting. A majority of the number of directors fixed pursuant
      to Section I above shall constitute a quorum except when a vacancy or vacancies
      exist, whereupon a majority of the directors then in office shall constitute
      a
      quorum for the transaction of business, provided that in no case shall less
      than
      one-third of the number of directors fixed pursuant to Section I above
      constitute a quorum. If at any meeting of the Board of Directors there shall
      be
      less than such a quorum, a majority of those present may adjourn the meeting
      from time to time. Every act or decision done or made by a majority of the
      directors present at a meeting duly held at which a quorum is present shall
      be
      regarded as the act of the Board of Directors unless a greater number is
      required by law, by the By-laws of the Corporation or by this Certificate of
      Incorporation.





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VI.
      Removal. Directors of the Corporation may be removed only for cause by the
      affirmative vote of the holders of at least eighty percent (80%) of the combined
      voting power of all shares of the capital stock of the Corporation issued and
      outstanding and entitled to vote generally in the election of directors, voting
      together as a single class.








VII.
      Vacancies. Any vacancy in the Board of Directors, however occurring, including
      (without limitation) a vacancy resulting from an increase in the number of
      directors, shall be filled only by a vote of a majority of the directors then
      in
      office, even if less than a quorum, or by a sole remaining director. A director
      elected to fill a vacancy shall be elected to hold office until the next
      election of the class for which such director shall have been chosen, subject
      to
      the election and qualification of his successor and to his earlier death,
      resignation or removal.





VIII.
      Preferred Stock. Notwithstanding the foregoing, whenever the holders of any
      one
      or more series of Preferred Stock issued by the Corporation after approval
      by
      the Board of Directors shall have the right, voting separately by class or
      series, to elect directors at an annual or special meeting of stockholders,
      the
      election, term of office, filling of vacancies and other features of such
      directorships shall be governed by the terms of this Certificate of
      Incorporation (including such terms as may be adopted by the Board of Directors
      pursuant to Section III of Article FOURTH of the Certificate of Incorporation)
      applicable thereto, such directors so elected shall not be divided into classes
      pursuant to this Article SIXTH, and the number of such directors shall not
      be
      counted in determining the maximum number of directors permitted under the
      foregoing provisions of this Article SIXTH, in each case unless expressly
      provided by such terms.





IX.
      Amendments to Article. Notwithstanding any other provisions of law, the
      Certificate of Incorporation or the By-laws of the Corporation, and
      notwithstanding the fact that a lesser percentage may be specified by law,
      the
      affirmative vote of the holders of at least eighty percent (80%) of the combined
      voting power of all shares of capital stock of the Corporation issued and
      outstanding and entitled to vote generally in the election of directors, voting
      together as a single class, shall be required to amend or repeal, or to adopt
      any provision inconsistent with, any provision of this Article
      SIXTH.





SEVENTH:
      No directors of the Corporation shall be personally liable to the Corporation
      or
      its stockholders for monetary damages for breach of fiduciary duty as a
      director, provided that this Article SEVENTH shall not eliminate or limit the
      liability of a director (i) for any breach of such director's duty of loyalty
      to
      the Corporation or its stockholders, (ii) for acts or omissions of such director
      not in good faith or which involve intentional misconduct or knowing violation
      of law, (iii) under Section 174 of the Delaware General Corporation Law, or
      (iv)
      for any transaction from which such director derived an improper personal
      benefit; nor shall this Article SEVENTH eliminate or limit the liability of
      a
      director for any act or omission occurring prior to the date this Article
      SEVENTH becomes effective.





EIGHTH:
      The Board of Directors is expressly authorized to adopt, amend and repeal the
      By-Laws of the Corporation.





NINETH:
      The Corporation shall, to the fullest extent permitted by Section 145 of the
      Delaware General Corporation Law as the same may be amended or supplemented,
      indemnify any and all persons whom it shall have power to indemnify from and
      against any and all expenses, liabilities or other matters.





TENTH:
      Whenever a compromise or arrangement is proposed between this Corporation and
      its creditors or any class of them and/or between this Corporation and its
      stockholders or any class of them, any court of equitable jurisdiction within
      the State of Delaware may, on the application in a summary way of this
      Corporation or of any creditor or stockholder thereof or on the application
      of
      any receiver or receivers appointed for this Corporation under the provisions
      of
      Section 291 of Title 8 of the Delaware Code or on the application of trustees
      in
      dissolution or of any receiver or receivers appointed for this Corporation
      under
      the provisions of Section 279 of Title 8 of the Delaware Code order a meeting
      of
      the creditors or class of creditors, and/or of the stockholders or class of
      stockholders of this Corporation, as the case may be, to be summoned in such
      manner as the said court directs. If a majority in number representing
      three-fourths in value of the creditors or class of creditors, and/or of the
      stockholders or class of stockholders of this Corporation, as the case may
      be,
      agree to any compromise or arrangement and to any reorganization of this
      Corporation as a consequence of such compromise or arrangement, the said
      compromise of arrangement and the said reorganization shall, if sanctioned
      by
      the court to which the said application has been made, be binding on all the
      creditors or class of creditors, and/or on all the stockholders or class of
      stockholders, of this Corporation, as the case may be, and also on this
      Corporation.








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