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                                                              Exhibit 3(i).3



                   CERTIFICATE OF POWERS, DESIGNATION, PREFERENCES,

                                RIGHTS AND LIMITATIONS

                                          OF

                         SERIES B CONVERTIBLE 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 meetings duly called and held on February 27 and May 16,

1996:

              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 B Convertible Preferred Stock:

              SECTION 3. DESIGNATION AND AMOUNT.  One Hundred Thousand 
         (100,000) shares of Preferred Stock, $.001 par value, are designated
         "Series B Convertible Preferred Stock" with the rights, preferences,
         privileges and restrictions specified herein


                                       1.

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         (the "Series B Preferred Stock"). Subject to Section 7 hereof, such
         number of shares may be increased or decreased by resolution of the
         Board of Directors.

            SECTION 2. DIVIDENDS AND DISTRIBUTIONS.  The holders of the Series
         B Preferred Stock shall be entitled to receive, when, as and if
         declared by the Board of Directors, out of funds legally available
         therefor, dividends at the rate per share equal to any dividend
         declared or paid per share to the Common Stock of the Corporation
         ("Common Stock").  The right to such dividends on the Series B
         Preferred Stock shall be non-cumulative.

            SECTION 3. VOTING RIGHTS.  Except as set forth herein, or as
         otherwise provided by law, holders of Series B 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. LIQUIDATION PREFERENCE. In the event of any liquidation,
         dissolution or winding up of the Corporation, either voluntary or
         involuntary (a "Liquidation Event"),  the holders of the Series B
         Preferred Stock shall be entitled to receive, prior and in preference
         to any distribution of any of the assets or surplus funds of the
         Corporation to the holders of the Common Stock or Junior Preferred
         Stock of the Corporation, an amount per share (as adjusted for any
         combinations, consolidations, stock distributions or stock dividends
         with respect to such shares) equal to the quotient of (a) $7,000,000
         divided by (b) the number of Series B Preferred Stock issued and
         outstanding as of the date of such Liquidation Event.  If upon the
         occurrence of such Liquidation Event, the assets and funds thus
         distributed among the holders of the Series B Preferred Stock shall be
         insufficient to permit the payment to such holders of the full
         aforesaid preferential amount, then the entire assets and funds of the
         Corporation legally available for distribution shall be distributed
         among the holders of the Series B Preferred Stock in proportion to the
         shares of Series B Preferred Stock then held by them.

           SECTION 5. CONVERSION.  Subject to the limitations set forth in
         Subsection (C) below, the Series B Preferred Stock shall convert only
         as follows:  

              (A)   AUTOMATIC CONVERSION.  The Series B Preferred Stock
         outstanding on May 17, 1998 (the "Automatic Conversion

                                       2.

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         Date") shall automatically convert on such date, in whole and not
         in part, into such number of fully paid and nonassessable shares of
         Common Stock equal to the quotient of $7,000,000 divided by the
         average closing price of the Corporation's Common Stock (as reported
         in THE WALL STREET JOURNAL, WESTERN ADDITION) for a period of thirty
         (30) trading days prior to the Automatic Conversion Date.

              (B)  CONVERSION AT CORPORATION'S OPTION.  At any time prior to
         the Automatic Conversion Date, the Corporation shall have the option,
         in its sole discretion, to convert the Series B Preferred Stock, in
         whole and not in part, into such number of fully paid and
         nonassessable shares of Common Stock equal to the quotient of
         $7,000,000 divided by the average closing price of the Corporation's
         Common Stock (as reported in THE WALL STREET JOURNAL, WESTERN
         ADDITION) for a period of thirty (30) trading days prior to date upon
         which the Corporation issues notice to the holders of Series B
         Preferred Stock of such optional conversion.

              (C)   LIMITATION ON CONVERTED SHARES.  The number of shares of
         Common Stock issuable upon conversion of the Series B Preferred Stock
         shall not be fewer than the quotient of $7,000,000 divided by two
         times the closing price of the Common Stock on May 17, 1996 (as
         reported in the WALL STREET JOURNAL, WESTERN EDITION) (the "Market
         Price"), nor greater than the quotient of $7,000,000 divided by
         one-half of the Market Price.

              (D)   ADJUSTMENTS FOR COMBINATIONS OR SUBDIVISIONS OF COMMON
         STOCK.  In the event the Corporation at any time or from time to time
         shall declare or pay any dividend on the Common Stock payable in
         Common Stock or in any right to acquire Common Stock, or shall effect
         a subdivision of the outstanding shares of Common Stock into a greater
         number of shares of Common Stock (by stock split, reclassification or
         otherwise), or in the event the outstanding shares of Common Stock
         shall be combined or consolidated, by reclassification or otherwise,
         into a lesser number of shares of Common Stock, then the maximum and
         minimum number of shares of Common Stock into which the Series B
         Preferred Stock may be converted, shall be proportionately decreased
         or increased, as appropriate.

              (E)   MECHANICS OF CONVERSION.  Before any holder of Series B
         Preferred Stock shall be entitled to receive shares of Common Stock,
         he shall surrender the certificate or certificates thereof, duly
         endorsed, at the office of the Corporation or of any transfer agent
         for such stock, and shall state therein the name or 

                                       3.

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         names in which he wishes the certificate or certificates for shares
         of Common Stock to be issued.  The Corporation shall, as soon as
         practicable thereafter, issue and deliver at such office to such
         holder of Series B Preferred Stock, a certificate or certificates
         for the number of shares of Common Stock to which he shall be
         entitled as aforesaid.  Such conversion shall be deemed to have been
         made immediately prior to the close of business on the Automatic
         Conversion Date or the Optional Conversion Date, as appropriate,
         and the person or persons entitled to receive the shares of Common
         Stock issuable upon such conversion shall be treated for all purposes
         as the record holder or holders of such shares of Common Stock on such
         date.

            (F)   RESERVATION OF STOCK ISSUABLE UPON CONVERSION.  The
         Corporation shall at all times reserve and keep available out of its
         authorized but unissued shares of Common Stock, solely for the purpose
         of effecting the conversion of the shares of the Series B Preferred
         Stock, such number of its shares of Common Stock as shall from time to
         time be sufficient to effect the conversion of all outstanding shares
         of the Series B Preferred Stock.

            (G)   FRACTIONAL SHARES.  No fractional share shall be issued upon
         the conversion of any share or shares of Series B Preferred Stock. 
         All shares of Common Stock (including fractions thereof) issuable upon
         conversion of Series B Preferred Stock shall be aggregated for
         purposes of determining whether the conversion would result in the
         issuance of any fractional share.  If, after the aforementioned
         aggregation, the conversion would result in the issuance of a fraction
         of a share of Common Stock, the Corporation shall, in lieu of issuing
         any fractional share, pay the holder otherwise entitled to such
         fraction a sum in cash equal to the closing price of the Common Stock
         on the date of conversion, multiplied by such fraction.

            (H)   REORGANIZATION, RECLASSIFICATION, CONSOLIDATION, MERGER OR
         SALE.  If any (i) reorganization of the capital stock of the
         Corporation, (ii) consolidation or merger of the Corporation in which
         the Corporation is not the surviving corporation, or (iii) sale of all
         or substantially all of the Corporation's assets to another
         corporation (each, an "Event") shall be effected in such a way that
         holders of Common Stock shall be entitled to receive securities, cash
         or other assets or property, the Automatic Conversion Date shall be
         accelerated to the date immediately preceding such Event, or such
         other date necessary to assure that any holder of Series B Preferred
         Stock receives such shares of stock, securities or other

                                       4.

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         assets or property as may be issued or payable with respect to or in
         exchange for shares of Common Stock.

            SECTION 6. NO REDEMPTION.  The shares of Series B Preferred Stock 
         shall not be redeemable. 

            SECTION 7. 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 Series B 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 Series B Preferred Stock, voting together as a
         single class.



                                       5.

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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













                                       6.