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                                                                       Exhibit 5


                      [MORRISON & FOERSTER LLP LETTERHEAD]





                           _________________ __, 1998


Anthra Pharmaceuticals, Inc.
103 Carnegie Center, Suite 102
Princeton, NJ  08540


Ladies and Gentlemen:

      At your request, we have examined the Registration Statement on Form S-1
filed by Anthra Pharmaceuticals, Inc., a Delaware corporation (the "Company"),
with the Securities and Exchange Commission (the "SEC") on March 11, 1998
(Registration No. 333-47725), as amended (collectively, the "Registration
Statement"), with exhibits as filed in connection therewith, and the form of
prospectus contained therein, relating to the registration under the Securities
Act of 1933, as amended (the "Securities Act"), of up to 2,300,000 units (the
"Units"), each Unit consisting of one share of the Company's common stock, $0.01
par value per share (the "Common Stock"), and one redeemable warrant to purchase
one share of Common Stock (the "Warrants"), of which 300,000 Units may be
purchased to cover over-allotments, if any. The Registration Statement also
registers (1) a warrant to be issued to the underwriter of the public offering
(the "Underwriter") to purchase 200,000 Units (the "Underwriter's Warrant"), (2)
the 200,000 Units (the "Underwriter's Units") issuable upon the exercise of the
Underwriter's Warrant, (3) the 200,000 shares of Common Stock underlying the
Underwriter's Units, (4) the 200,000 Warrants underlying the Underwriter's Units
and (5) the 200,000 shares of Common Stock underlying the Warrants underlying
the Underwriter's Units. The Units and the Underwriter's Warrant and the
securities underlying such Units and Underwriter's Warrant are collectively
referred to herein as the "Securities." The Securities are being sold to the
Underwriter pursuant to an Underwriting Agreement to be entered into by the
Company and the Underwriter.

      As counsel to the Company, we have examined such corporate records,
documents, instruments, certificates of public officials and of the Company and
such questions of law as we have deemed necessary for the purpose of rendering
the opinions set forth herein. In our examination, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to originals of all documents submitted to us as
certified, photostatic or conformed copies, and the authenticity of the
originals of all such latter documents. We have also assumed the due execution
and delivery of all documents where due execution and delivery are prerequisites
to the effectiveness thereof. We have relied upon certificates of public
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officials and certificates of officers of the Company for the accuracy of
material, factual matters contained therein which we have not independently
established.

      The opinions hereinafter expressed are subject to the following
qualifications and exceptions:

              (i) The effect of bankruptcy, insolvency, reorganization,
arrangement, moratorium or other similar laws relating to or affecting the
rights of creditors generally, including, without limitation, laws relating to
fraudulent transfers or conveyances, preferences and equitable subordination;

              (ii) Limitations imposed by general principles of equity upon the
availability of equitable remedies or the enforcement of provisions of the
Warrants or the Underwriter's Warrant; and the effect of judicial decisions
which have held that certain provisions are unenforceable where their
enforcement would violate the implied covenant of good faith and fair dealing,
or would be commercially unreasonable, or where their breach is not material;
and

              (iii) Provisions purporting to provide for indemnification under
certain circumstances may be unenforceable as violative of public policy, and
accordingly, we are unable to render an opinion as to the enforceability of such
provisions.

      Based on the foregoing and on all other instruments, documents and matters
examined in connection with rendering this opinion and subject to the
effectiveness of the Registration Statement with the SEC and to the registration
or qualification under the securities laws of the states in which the Securities
may be sold, upon the sale and issuance of the Securities in the manner referred
to in the Registration Statement and in accordance with the terms of the
Underwriting Agreement, we are of the opinion that:

      1. The issuance of the shares of Common Stock comprising a part of the
Units has been duly authorized by the Board of Directors of the Company, and
such shares, when issued, will be validly issued, fully paid and non-assessable
shares of the Company's Common Stock.

      2. The issuance of the Warrants (comprising a part of the Units) has been
duly authorized by the Board of Directors of the Company, and such Warrants when
issued will constitute legal, valid and binding obligations of the Company in
accordance with their terms.

      3. The issuance of the Underwriter's Warrant has been duly authorized by
the Board of Directors of the Company, and such Underwriter's Warrant when
issued 
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will constitute legal, valid and binding obligations of the Company, in
accordance with its terms.

      4. The shares of Common Stock issuable upon the exercise of the Warrants
have been duly authorized by the Board of Directors of the Company, and, upon
exercise of the Warrants in accordance with their terms and payment of the
exercise price therefor, will be validly issued, fully paid and non-assessable
shares of the Company's Common Stock.

      We express no opinion as to the applicability or effect of any laws,
orders or judgments of any state or jurisdiction other than federal securities
laws, the substantive laws of the State of New York and the General Corporation
Law of the State of Delaware. Further, our opinion is based solely upon existing
laws, rules and regulations, and we undertake no obligation to advise you of any
changes that may be brought to our attention after the date hereof.

      We consent to the use of our name under the caption "Legal Matters" in the
Prospectus, constituting part of the Registration Statement, and to the filing
of this opinion as an exhibit to the Registration Statement.

      By giving you this opinion and consent, we do not admit that we are
experts with respect to any part of the Registration Statement or Prospectus
within the meaning of the term "expert" as used in Section 11 of the Securities
Act or the rules and regulations promulgated thereunder by the SEC, nor do we
admit that we are in the category of persons whose consent is required under
Section 7 of the Securities Act.

      This letter is furnished by us to you solely for your benefit. Neither
this letter nor any opinion expressed herein may be relied upon by, nor may
copies be delivered or disclosed to, any other person or entity without our
prior written consent.



                                Very truly yours,



                                Morrison & Foerster LLP