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                                                                     EXHIBIT 4.5

                        CONVERTIBLE PROMISSORY AGREEMENT

$10,000                                                         January 10, 2001

This Agreement by and between, PARACELSIAN, INC., a Delaware corporation with an
address at 222 Langmuir Laboratories, Cornell Technology Park, Ithaca, NY 14850
(hereinafter called "Company") and Floyd Hasselriis with an address at 52
Seasongood Road, Forest Hills, New York 11375 (hereinafter called "Note
Holder").

WITNESSETH:

WHEREAS, Note Holder is willing to lend Company the aggregate sum of Ten
Thousand Dollars ($10,000) as evidenced by this Convertible Promissory Agreement
(hereinafter called "Note").

In consideration of the mutual covenants and conditions herein contained, the
parties hereby agree, represent and warrant as follows:

     A.   The Company authorizes the issuance of this Note in the aggregate
          principal amount of $10,000 to be dated January 10, 2001, to mature on
          January 9, 2002 and to bear interest on the unpaid principal thereof
          at the rate of ten percent (10%) per annum until maturity.

     B.   The Note Holder at any time up to and including the maturity date but
          not thereafter may convert the Note into as many shares of Restricted
          Common Stock of the Company as the principal and accrued interest of
          the Note so converted in a multiple of $.40 per share, and upon
          surrender of this Agreement representing the Note to the Company at
          its principal office.

     C.   No fractional share of Common Stock shall be issued upon conversion of
          the Note. Upon conversion of the Note, any remaining accrued and
          unpaid interest and principal shall be paid to the Note Holder by the
          Company.

     D.   In case the Company shall at any time divide its outstanding shares of
          Common Stock into a greater number of shares, the conversion price in
          effect immediately prior to such subdivision should be proportionately
          reduced, and, conversely, in the case of outstanding shares of Common
          Stock of the Company shall be combined into a smaller number of
          shares, the actual conversion price in effect immediately prior to
          such combination shall be proportionately increased.

     E.   This Agreement may not be modified, amended or terminated except by
          written agreement executed by all the parties hereto.

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IN WITNESS THEREOF, this Note has been duly executed on the day and year first
above written.

PARACELSIAN, INC.


By:     /s/ T. Colin Campbell
    -------------------------------------
        T. Colin Campbell
        President & CEO


[Corporate Seal]


Attest:


/s/ Gary G. Chabot              Secretary
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