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                                                           Exhibit 3(i).1

                  AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                          OF
                                    COCENSYS, INC.
                                           
                                      I.

                                           
    The name of this corporation is CoCensys, Inc.

                                      II.

    The address of the registered office of the corporation in the State of
Delaware is 32 Loockerman Square, Suite L-100, City of Dover, County of Kent,
and the name of the registered agent of the corporation in the State of Delaware
at such address is the Prentice Hall Corporation System.  

                                      III.

    The purpose of this corporation is to engage in any lawful act or activity
for which a corporation may be organized under the General Corporation Law of
the State of Delaware.

                                      IV.

    A.   This corporation is authorized to issue two classes of stock to be
designated, respectively, "Common Stock" and "Preferred Stock."  The total
number of shares which the corporation is authorized to issue is thirty-five
million (35,000,000) shares.  Thirty million (30,000,000) shares shall be Common
Stock, each having a par value of one-tenth of One Cent ($.001).  Five million
(5,000,000) shares shall be Preferred Stock, each having a par value of
one-tenth of One Cent ($.001).

    B.   The Preferred Stock may be issued from time to time in one or more
series.  The Board of Directors is hereby authorized, by filing a certificate
pursuant to the Delaware General Corporation Law, to fix or alter from time to
time the designation, powers, preferences and rights of the shares of each such
series and the qualifications, limitations or restrictions thereof, including
without limitation the dividend rights, dividend rate, conversion rights, voting
rights, rights and terms of redemption (including sinking fund provisions),
redemption price or prices, and the liquidation preferences of any wholly
unissued series of Preferred Stock, and to establish from time to time the
number of shares constituting any such series and the designation thereof, or
any of them (a "Preferred Stock Designation"); and to increase or decrease the
number of shares of any series subsequent to the issuance of shares of that
series, but not below the number of shares of such series then outstanding.  In
case the number of shares of any series shall be decreased in accordance with
the foregoing sentence, the shares constituting such decrease shall resume the
status that they had prior to the adoption of the resolution originally fixing
the number of shares of such series.

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    C.   No share or shares of any series of Preferred Stock acquired by the
Corporation by reason of redemption, purchase, conversion or otherwise shall be
reissued as part of such series, and the Board of Directors is authorized,
pursuant to Section 243 of the Delaware General Corporation law, to retire any
such share or shares.  The retirement of any such share or shares shall not
reduce the total authorized number of shares of Preferred Stock.

                                          V.

    For the management of the business and for the conduct of the affairs of
the corporation, and in further definition, limitation and regulation of the
powers of the corporation, of its directors and of its stockholders or any class
thereof, as the case may be, it is further provided that:

    A.   The management of the business and the conduct of the affairs of the
corporation shall be vested in its Board of Directors.  The number of directors
which shall constitute the whole Board of Directors shall be fixed exclusively
by one or more resolutions adopted by the Board of Directors.

    Following the closing of the initial public offering pursuant to an
effective registration statement under the Securities Act of 1933, as amended
(the "1933 Act"), covering the offer and sale of Common Stock to the public (the
"Initial Public Offering"), the directors shall be divided into three (3)
classes designated as Class I, Class II and Class III, respectively.  Directors
shall be assigned to each class in accordance with a resolution or resolutions
adopted by the Board of Directors.  At the first annual meeting of stockholders
following the closing of the Initial Public Offering, the term of office of the
Class I directors shall expire and Class I directors shall be elected for a full
term of three (3) years.  At the second annual meeting of stockholders following
the closing of the Initial Public Offering, the term of office of the Class II
directors shall expire and Class II directors shall be elected for a full term
of three (3) years.  At the third annual meeting of stockholders following the
closing of the Initial Public Offering, the term of office of the Class III
directors shall expire and Class III directors shall be elected for a full term
of three years.  At each succeeding annual meeting of stockholders, directors
shall be elected for a full term of three (3) years to succeed the directors of
the class whose terms expire at such annual meeting.

    Notwithstanding the foregoing provisions of this Article, each director
shall serve until his successor is duly elected and qualified or until his
death, resignation or removal.  No decrease in the number of directors
constituting the Board of Directors shall shorten the term of any incumbent
director.

    Any vacancies on the Board of Directors resulting from death, resignation,
disqualification, removal or other causes shall be filled by either (i) the
affirmative vote of the holders of a majority of the voting power of the
then-outstanding shares of voting stock of the corporation entitled to vote
generally in the election of directors (the "Voting Stock") voting together as a
single class; or (ii) by the affirmative vote of a majority of the remaining
directors then in office, even though less than a quorum of the Board of
Directors.  Newly created directorships resulting from any increase in the
number of directors shall, unless the Board of 

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Directors determines by resolution that any such newly created directorship
shall be filled by the stockholders, be filled only by the affirmative vote of
the directors then in office, even though less than a quorum of the Board of
Directors.  Any director elected in accordance with the preceding sentence shall
hold office for the remainder of the full term of the class of directors in
which the new directorship was created or the vacancy occurred and until such
director's successor shall have been elected and qualified.

    B.   The Bylaws may be altered or amended or new Bylaws adopted by the
affirmative vote of at least sixty-six and two-thirds percent (66-2/3%) of the
voting power of all of the then-outstanding shares of the Voting Stock.  In
furtherance and not in limitation of the power conferred by statute, the Board
of Directors is expressly authorized to adopt, amend, supplement or repeal the
Bylaws.

    C.   The directors of the corporation need not be elected by written ballot
unless the Bylaws so provide.

    D.   Following the closing of the Initial Public Offering, no action shall
be taken by the stockholders of the corporation except at an annual or special
meeting of stockholders called in accordance with the Bylaws and no action shall
be taken by the stockholders by written consent.

    E.   Advance notice of stockholder nominations for the election of
directors and of business to be brought by stockholders before any meeting of
the stockholders of the corporation shall be given in the manner provided in the
Bylaws of the corporation.

    F.   Any director, or the entire Board of Directors, may be removed from
office at any time (i) with cause by the affirmative vote of the holders of at
least a majority of the voting power of all of the then-outstanding shares of
the Voting Stock, voting together as a single class; or (ii) without cause by
the affirmative vote of the holders of at least sixty-six and two-thirds percent
(66-2/3%) of the voting power of all of the then-outstanding shares of the
Voting Stock.

                                 VI.

    (1)  A director of the corporation shall not be personally liable to the
corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived any improper
personal benefit.  If the Delaware General Corporation Law is amended after
approval by the stockholders of this article to authorize corporate action
further eliminating or limiting the personal liability of directors, then the
liability of a director of the corporation shall be eliminated or limited to the
fullest extent permitted by the Delaware General Corporation Law, as so amended.

    (2)  The corporation is authorized to provide indemnification of agents (as
defined in Section 145 of the Delaware General Corporation Law) for breach of
duty to the corporation and its stockholders through bylaw provisions, through
agreements with the agents, and/or through 


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stockholder resolutions, or otherwise, in excess of the indemnification
otherwise permitted by Section 145 of the Delaware General Corporation Law,
subject to the limitations on such excess indemnification set forth in Section
102 of the Delaware General Corporation Law.

    (3)  Any repeal or modification of this Article VI by the stockholders of
the corporation shall not adversely affect any right or protection of a director
of the corporation existing at the time of such repeal or modification.

                                VII.

    Notwithstanding any other provisions of this Amended and Restated
Certificate of Incorporation or any provision of law which might otherwise
permit a lesser vote or no vote, but in addition to any affirmative vote of the
holders of any particular class or series of the Voting Stock required by law,
this Amended and Restated Certificate of Incorporation or any Preferred Stock
Designation, the affirmative vote of the holders of at least sixty-six and
two-thirds percent (66-2/3%) of the voting power of all of the then-outstanding
shares of the Voting Stock, voting together as a single class, shall be required
to alter, amend or repeal Article V or Article IX.

                                VIII.

    The corporation is to have perpetual existence.

                                IX.

    The corporation reserves the right to amend, alter, change or repeal any
provision contained in this Amended and Restated Certificate of Incorporation,
in the manner now or hereafter prescribed by statute, except as provided in
Article VII of this Certificate, and all rights conferred upon the stockholders
herein are granted subject to this right. 


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