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                                                                 Exhibit 3(i).2

                              CERTIFICATE OF DESIGNATION
                                          OF
                    SERIES A JUNIOR PARTICIPATING PREFERRED STOCK
                                          OF
                                    COCENSYS, INC.
                           (Pursuant to Section 151 of the
                          Delaware General Corporation Law)
                                           

    COCENSYS, INC., a corporation organized and existing under the General
Corporation Law of the State of Delaware (hereinafter called the "Corporation"),
hereby certifies that the following resolution was adopted by the Board of
Directors of the Corporation as required by Section 151 of the General
Corporation Law at a meeting duly called and held on April 25, 1995:

              RESOLVED, that pursuant to the authority granted to and vested in
         the Board of Directors of the Corporation in accordance with the
         provisions of its Amended and Restated Certificate of Incorporation,
         the Board of Directors hereby creates a series of Preferred Stock, par
         value $.001 per share, of the Corporation and hereby states the
         designation and number of shares, and fixes the relative rights,
         preferences and limitations thereof (in addition to the provisions set
         forth in the Restated Certificate of Incorporation of the Corporation,
         which are applicable to the Preferred Stock of all classes and
         series), as follows:

         Series A Junior Participating Preferred Stock:

              SECTION 1.  DESIGNATION AND AMOUNT.  Three Hundred Fifty Thousand
         (350,000) shares of Preferred Stock, $.001 par value, are designated
         "Series A Junior Participating Preferred Stock" with the rights,
         preferences, privileges and restrictions 


                                          1.


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         specified herein (the "Junior Preferred Stock").  Such number of
         shares may be increased or decreased by resolution of the Board of
         Directors; PROVIDED, that no decrease shall reduce the number of
         shares of Junior Preferred Stock to a number less than the number of
         shares then outstanding plus the number of shares reserved for
         issuance upon the exercise of outstanding options, rights or warrants
         or upon the conversion of any outstanding securities issued by the
         Corporation convertible into Junior Preferred Stock.

              SECTION 2.  DIVIDENDS AND DISTRIBUTIONS.

              (A)  Subject to the rights of the holders of any shares of any
         series of Preferred Stock (or any similar stock) ranking prior and
         superior to the Junior Preferred Stock with respect to dividends, the
         holders of shares of Junior Preferred Stock, in preference to the
         holders of Common Stock, par value $.001 per share (the "Common
         Stock"), of the Corporation, and of any other junior stock, shall be
         entitled to receive, when, as and if declared by the Board of
         Directors out of funds legally available for the purpose, quarterly
         dividends payable in cash on the first day of March, June, September
         and December in each year (each such date being referred to herein as
         a "Quarterly Dividend Payment Date"), commencing on the first
         Quarterly Dividend Payment Date after the first issuance of a share or
         fraction of a share of Junior Preferred Stock, in an amount per share
         (rounded to the nearest cent) equal to the greater of (a) $l.00 or (b)
         subject to the provision for adjustment hereinafter set forth, 100
         times the aggregate per share amount of all cash dividends, and 100
         times the aggregate per share amount (payable in kind) of all non-cash
         dividends or other distributions, other than a dividend payable in
         shares of Common Stock or a subdivision of the outstanding shares of
         Common Stock (by reclassification or otherwise) declared on the Common
         Stock since the immediately preceding Quarterly Dividend Payment Date
         or, with respect to the first Quarterly Dividend Payment Date, since
         the first issuance of any share or fraction of a share of Junior
         Preferred Stock.  In the event the Corporation shall at any time
         declare or pay any dividend on the Common Stock payable in shares of
         Common Stock, or effect a subdivision or combination or consolidation
         of the outstanding shares of Common Stock (by reclassification or
         otherwise than by payment of a dividend in shares of Common Stock)
         into a greater or lesser number of shares of Common Stock, then in
         each such case the amount to which holders of shares of Junior
         Preferred 

                                          2.


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         Stock were entitled immediately prior to such event under clause (b)
         of the preceding sentence shall be adjusted by multiplying such amount
         by a fraction, the numerator of which is the number of shares of
         Common Stock outstanding immediately after such event and the
         denominator of which is the number of shares of Common Stock that were
         outstanding immediately prior to such event.

              (B)  The Corporation shall declare a dividend or distribution on
         the Junior Preferred Stock as provided in paragraph (A) of this
         Section immediately after it declares a dividend or distribution on
         the Common Stock (other than a dividend payable in shares of Common
         Stock); provided that, in the event no dividend or distribution shall
         have been declared on the Common Stock during the period between any
         Quarterly Dividend Payment Date and the next subsequent Quarterly
         Dividend Payment Date, a dividend of $1.00 per share on the Junior
         Preferred Stock shall nevertheless be payable on such subsequent
         Quarterly Dividend Payment Date.

              (C)  Dividends shall begin to accrue and be cumulative on
         outstanding shares of Junior Preferred Stock from the Quarterly
         Dividend Payment Date next preceding the date of issue of such shares,
         unless the date of issue of such shares is prior to the record date
         for the first Quarterly Dividend Payment Date, in which case dividends
         on such shares shall begin to accrue from the date of issue of such
         shares, or unless the date of issue is a Quarterly Dividend Payment
         Date or is a date after the record date for the determination of
         holders of shares of Junior Preferred Stock entitled to receive a
         quarterly dividend and before such Quarterly Dividend Payment Date, in
         either of which events such dividends shall begin to accrue and be
         cumulative from such Quarterly Dividend Payment Date.  Accrued but
         unpaid dividends shall not bear interest.  Dividends paid on the
         shares of Junior Preferred Stock in an amount less than the total
         amount of such dividends at the time accrued and payable on such
         shares shall be allocated pro rata on a share-by-share basis among all
         such shares at the time outstanding.  The Board of Directors may fix a
         record date for the determination of holders of shares of Junior
         Preferred Stock entitled to receive payment of a dividend or
         distribution declared thereon, which record date shall be not more
         than 60 days prior to the date fixed for the payment thereof.


                                          3.


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              SECTION 3.  VOTING RIGHTS.  The holders of shares of Junior
         Preferred Stock shall have the following voting rights:

              (A)  Subject to the provision for adjustment hereinafter set
         forth, each share of Junior Preferred Stock shall entitle the holder
         thereof to 100 votes on all matters submitted to a vote of the
         stockholders of the Corporation.  In the event the Corporation shall
         at any time declare or pay any dividend on the Common Stock payable in
         shares of Common Stock, or effect a subdivision or combination or
         consolidation of the outstanding shares of Common Stock (by
         reclassification or otherwise than by payment of a dividend in shares
         of Common Stock) into a greater or lesser number of shares of Common
         Stock, then in each such case the number of votes per share to which
         holders of shares of Junior Preferred Stock were entitled immediately
         prior to such event shall be adjusted by multiplying such number by a
         fraction, the numerator of which is the number of shares of Common
         Stock outstanding immediately after such event and the denominator of
         which is the number of shares of Common Stock that were outstanding
         immediately prior to such event.

              (B)  Except as otherwise provided herein, in any other
         Certificate of Determination of Preferences creating a series of
         Preferred Stock or any similar stock, or by law, the holders of shares
         of Junior Preferred Stock and the holders of shares of Common Stock
         and any other capital stock of the Corporation having general voting
         rights shall vote together as one class on all matters submitted to a
         vote of stockholders of the Corporation.

              (C)  Except as set forth herein, or as otherwise provided by law,
         holders of Junior Preferred Stock shall have no special voting rights
         and their consent shall not be required (except to the extent they are
         entitled to vote with holders of Common Stock as set forth herein) for
         taking any corporate action.

              SECTION 4.  CERTAIN RESTRICTIONS.

              (A)  Whenever quarterly dividends or other dividends or
         distributions payable on the Junior Preferred Stock as provided in
         Section 2 are in arrears, thereafter and until all accrued and unpaid
         dividends and distributions, whether or not declared, on shares of
         Junior Preferred Stock outstanding shall have been paid in full, the
         Corporation shall not:


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                     (I)     declare or pay dividends, or make any other
         distributions, on any shares of stock ranking junior (either as to
         dividends or upon liquidation, dissolution or winding up) to the
         Junior Preferred Stock;

                    (II)     declare or pay dividends, or make any other
         distributions, on any shares of stock ranking on a parity (either as
         to dividends or upon liquidation, dissolution or winding up) with the
         Junior Preferred Stock, except dividends paid ratably on the Junior
         Preferred Stock and all such parity stock on which dividends are
         payable or in arrears in proportion to the total amounts to which the
         holders of all such shares are then entitled;

                   (III)     redeem or purchase or otherwise acquire for
         consideration shares of any stock ranking junior (either as to
         dividends or upon liquidation, dissolution or winding up) to the
         Junior Preferred Stock, provided that the Corporation may at any time
         redeem, purchase or otherwise acquire shares of any such junior stock
         in exchange for shares of any stock of the Corporation ranking junior
         (either as to dividends or upon dissolution, liquidation or winding
         up) to the Junior Preferred Stock; or

                    (IV)     redeem or purchase or otherwise acquire for
         consideration any shares of Junior Preferred Stock, or any shares of
         stock ranking on a parity with the Junior Preferred Stock, except in
         accordance with a purchase offer made in writing or by publication (as
         determined by the Board of Directors) to all holders of such shares
         upon such terms as the Board of Directors, after consideration of the
         respective annual dividend rates and other relative rights and
         preferences of the respective series and classes, shall determine in
         good faith will result in fair and equitable treatment among the
         respective series or classes.

              (B)  The Corporation shall not permit any subsidiary of the
         Corporation to purchase or otherwise acquire for consideration any
         shares of stock of the Corporation unless the Corporation could, under
         paragraph (A) of this Section 4, purchase or otherwise acquire such
         shares at such time and in such manner.

              SECTION 5.  REACQUIRED SHARES.  Any shares of Junior Preferred
         Stock purchased or otherwise acquired by the Corporation in any manner
         whatsoever shall be retired and cancelled promptly after the
         acquisition thereof.  All such shares shall upon their 


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         cancellation become authorized but unissued shares of Preferred Stock
         and may be reissued as part of a new series of Preferred Stock subject
         to the conditions and restrictions on issuance set forth herein, in
         the Restated Certificate of Incorporation, or in any other Certificate
         of Determination of Preferences creating a series of Preferred Stock
         or any similar stock or as otherwise required by law.

              SECTION 6.  LIQUIDATION, DISSOLUTION OR WINDING UP.  Upon any
         liquidation, dissolution or winding up of the Corporation, no
         distribution shall be made (1) to the holders of shares of stock
         ranking junior (either as to dividends or upon liquidation,
         dissolution or winding up) to the Junior Preferred Stock unless, prior
         thereto, the holders of shares of Junior Preferred Stock shall have
         received $100 per share, plus an amount equal to accrued and unpaid
         dividends and distributions thereon, whether or not declared, to the
         date of such payment, provided that the holders of shares of Junior
         Preferred Stock shall be entitled to receive an aggregate amount per
         share, subject to the provision for adjustment hereinafter set forth,
         equal to 100 times the aggregate amount to be distributed per share to
         holders of shares of Common Stock, or (2) to the holders of shares of
         stock ranking on a parity (either as to dividends or upon liquidation,
         dissolution or winding up) with the Junior Preferred Stock, except
         distributions made ratably on the Junior Preferred Stock and all such
         parity stock in proportion to the total amounts to which the holders
         of all such shares are entitled upon such liquidation, dissolution or
         winding up.  In the event the Corporation shall at any time declare or
         pay any dividend on the Common Stock payable in shares of Common
         Stock, or effect a subdivision or combination or consolidation of the
         outstanding shares of Common Stock (by reclassification or otherwise
         than by payment of a dividend in shares of Common Stock) into a
         greater or lesser number of shares of Common Stock, then in each such
         case the aggregate amount to which holders of shares of Junior
         Preferred Stock were entitled immediately prior to such event under
         the proviso in clause (1) of the preceding sentence shall be adjusted
         by multiplying such amount by a fraction the numerator of which is the
         number of shares of Common Stock outstanding immediately after such
         event and the denominator of which is the number of shares of Common
         Stock that were outstanding immediately prior to such event.

              SECTION 7.  CONSOLIDATION, MERGER, ETC. In case the Corporation
         shall enter into any consolidation, merger, combination or other
         transaction in which the shares of Common Stock are exchanged for or
         changed into other stock or securities, cash and/or any other
         property, then in any such case each share of Junior Preferred Stock
         shall at the same time be similarly exchanged or changed into an
         amount per share, subject to the provision for adjustment hereinafter
         set forth, equal to 100 times the aggregate amount of stock,
         securities, cash and/or 


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         any other property (payable in kind), as the case may be, into which
         or for which each share of Common Stock is changed or exchanged.  In
         the event the Corporation shall at any time declare or pay any
         dividend on the Common Stock payable in shares of Common Stock, or
         effect a subdivision or combination or consolidation of the
         outstanding shares of Common Stock (by reclassification or otherwise
         than by payment of a dividend in shares of Common Stock) into a
         greater or lesser number of shares of Common Stock, then in each such
         case the amount set forth in the preceding sentence with respect to
         the exchange or change of shares of Junior Preferred Stock shall be
         adjusted by multiplying such amount by a fraction, the numerator of
         which is the number of shares of Common Stock outstanding immediately
         after such event and the denominator of which is the number of shares
         of Common Stock that were outstanding immediately prior to such event.

              SECTION 8.  NO REDEMPTION.  The shares of Junior Preferred Stock
         shall not be redeemable.

              SECTION 9.  RANK.  The Junior Preferred Stock shall rank, with
         respect to the payment of dividends and the distribution of assets,
         junior to all series of any other class of the Corporation's Preferred
         Stock.

              SECTION 10.  AMENDMENT.  The Restated Certificate of
         Incorporation of the Corporation shall not be amended in any manner
         which would materially alter or change the powers, preferences or
         special rights of the Junior Preferred Stock so as to affect them
         adversely without the affirmative vote of the holders of at least
         two-thirds of the outstanding shares of Junior Preferred Stock, voting
         together as a single class.


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    IN WITNESS WHEREOF the undersigned have executed this certificate as of May
16, 1996.

                                  /s/ Daniel L. Korpolinski
                                  ______________________________________
                                  Daniel L. Korpolinski
                                  President and Chief Executive Officer


                                  /s/ Alan C. Mendelson
                                  _______________________________________
                                  Alan C. Mendelson
                                  Secretary


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