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                                                               Exhibit 10(l)(ii)

                       AMENDMENT TO EMPLOYMENT AGREEMENT

                 AMENDMENT TO EMPLOYMENT AGREEMENT, by and between CN
Biosciences, Inc., a Delaware corporation (formerly Calbiochem- Novabiochem
International, Inc., the "Company"), and Stelios B. Papadopoulos (the
"Employee"), dated as of February 27, 1997.

                 WHEREAS, the Company and the Employee are parties to an
Employment Agreement, dated as of January 1, 1996 (the "Employment Agreement");
and

                 WHEREAS, the Company and the Employee wish to amend the
Employment Agreement with respect to payment to the Employee in connection with
the termination of the Employee's employment under certain circumstances.

                 NOW, THEREFORE, in connection with the mutual covenants
hereinafter set forth and for other good and valuable consideration, the
parties hereto agree as follows:

                 Section 1.  Amendments to Employment Agreement.

                 Paragraph 8 of the Employment Agreement is amended by (A)
adding a new subparagraph (b) to such paragraph to read as follows:

                          "(b)  In the event that the Employee resigns during
         the 90-day period following the effective date of a "Change of
         Control" (as defined below) of the Company, the Employee shall receive
         salary continuation pay for 12 months from the date of such
         termination equal to the Employee's base salary in effect at the time
         of the Change of Control.  For purposes of this Agreement, "Change of
         Control" shall mean (a) an acquisition (other than directly from the
         Company) by an individual, entity or a group (excluding the Company,
         an employee benefit plan of the Company or E.M. Warburg, Pincus & Co.,
         LLC or its affiliates) of 50% or more of the Company's Common Stock,
         par value $.01 per share, or voting securities; (b) a change in a
         majority of the Company's current Board of Directors (the "Incumbent
         Board") (excluding any persons approved by a vote of at least a
         majority of the Incumbent Board or persons elected with the
         concurrence of a majority of the Incumbent Board); or (c) the
         consummation of a complete liquidation or dissolution of the Company
         or a merger, consolidation or sale of all or substantially all of the
         Company's assets (collectively, a "Business Combination") other than a
         Business Combination in which all or substantially all of the
         Company's stockholders receive 50% or more of the stock of the Company
         resulting from the Business Combination, at least a majority of the
         board of directors of the resulting





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         corporation were members of the Incumbent Board, and after which no
         Person owns 50% or more of the stock of the resulting corporation, who
         did not own such stock immediately before the Business Combination.";

(B) renumbering existing subparagraphs (b), (c) and (d) of such paragraph to
become subparagraphs (c), (d) and (e), respectively.

                 Paragraph 9 of the Employment Agreement is amended in its
entirety to read as follows:

                          "9.  Stock Options.  If this Agreement is terminated
         pursuant to either paragraph 8(a)(iii) or paragraph 8(b) above, any
         stock options relating to the Company's Common Stock, par value $.01
         per share, then held by the Employee shall become exercisable to the
         full extent that they would otherwise have become exercisable on
         January 4, 1998, without regard to any restrictions or deferrals of
         the right to exercise such options upon such termination, and the
         Employee shall have the right to exercise such options during the
         30-day period following such termination."

                 Section 2.  Governing Law.  This Agreement shall be governed
by and construed and enforced in accordance with the laws of the State of
California without giving effect to the choice of law or conflict of laws
provisions thereof.

                 Section 3.  Entire Agreement.  This Agreement contains the
entire agreement of the parties with respect to the subject matter herein and
supersedes any and all agreements or understandings, written or oral, between
the Employee and the Company or any of the Company's principal stockholders,
affiliates or subsidiaries.  This Agreement may be changed only by an agreement
in writing signed by each of the parties hereto.





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                 IN WITNESS WHEREOF, the parties have executed this Agreement
as of the day first hereinabove written.



                                       CN BIOSCIENCES, INC.

                                       By:    /s/ James G. Stewart
                                          -------------------------------------
                                          Name:   James G. Stewart
                                          Title:  Vice President,
                                                  Administration, Chief
                                                  Financial Officer and
                                                  Secretary

                                       EMPLOYEE

                                       /s/ Stelios B. Papadopoulos
                                       ----------------------------------------
                                           Stelios B. Papadopoulos





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