POWER OF ATTORNEY


         The undersigned, as a Section 16 and Section 13(d) reporting person of
Rexahn Pharmaceuticals, Inc. (the "Company"), hereby constitutes and appoints
each of Ted T.H. Jeong, Chang H. Ahn and Inok Ahn the undersigned's true and
lawful attorneys-in-fact to:

         1.   Complete and execute forms and schedules and all amendments
thereto as such attorneys-in-fact shall in their discretion determine to be
required or advisable pursuant to Sections 16 and 13(d) of the Securities
Exchange Act of 1934 (as amended) and the rules and regulations promulgated
thereunder, or any successor laws and regulations, as a consequence of the
undersigned's ownership, acquisition or disposition of securities of the
Company; and

         2.   Do all acts necessary in order to file such forms and schedules
with the Securities and Exchange Commission, any securities exchange or national
association, the Company and such other person or agency as the
attorneys-in-fact shall deem appropriate.

         The undersigned hereby ratifies and confirms all that said
attorneys-in-fact and agent shall do or cause to be done by virtue hereof. The
undersigned acknowledges that the foregoing attorneys-in-fact, in serving in
such capacity at the request of the undersigned, are not assuming, nor is the
Company assuming, any of the undersigned's responsibilities to comply with
Sections 16 and 13(d) of the Securities Exchange Act of 1934 (as amended).

         This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file forms and schedules with respect to
the undersigned's holdings of and transactions in securities issued by the
Company, unless earlier revoked by the undersigned in a signed writing delivered
to the Company and the foregoing attorneys-in-fact.

         IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney
to be executed as of this 16th day of May, 2005.


            Signature                                        Date
            ---------                                        ----


/s/ Chang H. Ahn                                         May 16, 2005
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Name: Chang H. Ahn