EXHIBIT 5.1

January 13, 2004

Manhattan Pharmaceuticals, Inc.
787 Seventh Avenue, 48th Floor

New York, NY    10019

         RE:      Registration Statement on Form SB-2

Gentlemen:

         We have acted as counsel to Manhattan Pharmaceuticals, Inc., a Delaware
corporation (the "Company"), in connection with the preparation of a
registration statement on Form SB-2 (the "Registration Statement") to be filed
by the Company with the Securities and Exchange Commission on or about January
13, 2004 relating to the registration under the Securities Act of 1933, as
amended (the "Securities Act"), of the resale by the selling stockholders
identified in the Registration Statement of an aggregate of 21,029,163 shares of
the Company's common stock, $.001 par value per share, consisting of 7,591,703
issued and outstanding shares (the "Shares") of common stock, 10,000,000 shares
of common stock issuable upon conversion of the Series A Convertible Preferred
Stock (the "Conversion Shares") and 3,437,460 shares (the "Warrant Shares") of
common stock issuable upon the exercise of various outstanding warrants (the
"Warrants"). This opinion is being furnished in accordance with the requirements
of Item 601(b)(5) of Regulation S-B under the Securities Act.

         In connection with the rendering of this opinion, we have examined and
are familiar with originals or copies, certified or otherwise identified to our
satisfaction, of (i) the Registration Statement; (ii) the Certificate of
Incorporation and the Bylaws of the Company, as amended, each as currently in
effect; (iii) certain resolutions adopted by the Board of Directors of the
Company relating to the issuance of the shares covered by the Registration
Statement, the preparation and filing of the Registration Statement and certain
related matters; and (iv) such other documents, certificates and records as we
deemed necessary or appropriate as a basis for the opinions expressed herein.

         In our examination, we have assumed the genuineness of all signatures,
the legal capacity of natural persons, the authenticity of all documents
submitted to us as originals, the conformity to original documents of all
documents submitted to us as certified, conformed or photostatic copies and the
authenticity of the originals of such copies. As to any facts material to the
opinions expressed herein which we have not independently established or
verified, we have relied upon statements and representations of officers and
other representatives of the Company and others. We are attorneys licensed to
practice in the State of Minnesota and the opinions expressed herein are limited
to the laws of the State of Minnesota and the federal securities laws of the
United States.

         Based upon and subject to the limitations, qualifications, exceptions
and assumptions set forth herein, it is our opinion that:

         1. The Shares have been duly authorized and are validly issued, fully
paid and nonassessable.

         2. The Warrant Shares have been duly authorized and, when issued
against payment of the requisite exercise price, will be validly issued, fully
paid and nonassessable.




Manhattan Pharmaceuticals, Inc.
January 13, 2004
Page 2

         3. The Conversion Shares have been duly authorized and, when issued
upon conversion of the Series A Convertible Preferred Stock in accordance with
the terms of such convertible stock, will be validly issued, fully paid and
non-assessable.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. We also consent to the reference to our name under the
caption "Validity of Common Stock" in the prospectus filed as part of the
Registration Statement.


                                        Very truly yours,

                                        /s/ MASLON EDELMAN BORMAN & BRAND, LLP