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Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Quarterly Report on Form 10-Q of NitroMed, Inc. (the "Company") for the period ended September 30, 2003 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Michael D. Loberg, President and Chief Executive Officer, hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1)

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and



(2)

The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: December 18, 2003

/s/  MICHAEL D. LOBERG Michael D. Loberg
President and Chief Executive Officer

        A signed original of this written statement required by Section 906 has been provided to NitroMed, Inc. and will be retained by NitroMed, Inc. and furnished to the SEC or its staff upon request.

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CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002