Document:

<PAGE>   1

                                                                    EXHIBIT 10.1

                            SHARE TRANSFER AGREEMENT

                           ---------------------------

                                  By and Among

                             Nissan Motor Co., Ltd.
                                       and
                    Structural Dynamics Research Corporation
                                       and
                            Mechanical Dynamics, Inc.

                          ----------------------------

                                       5

<PAGE>   2

                            SHARE TRANSFER AGREEMENT

This SHARE TRANSFER AGREEMENT, dated as of November 17, 2000, is entered into by
and between Nissan Motor Co., Ltd., a corporation organized and existing under
the laws of Japan and having its principal place of business at 17-1, Ginza
6-chome, Chuo-ku, Tokyo, Japan and its registered address at No. 2, Takara-cho,
Kanagawa-ku, Yokohama-shi, Kanagawa-ken, Japan ("Nissan"), Structural Dynamics
Research Corporation, a corporation organized and existing under the laws of the
State of Ohio, U.S.A. and having its principal place of business at 2000 Eastman
Drive, Milford, Ohio 45150, U.S.A. ("SDRC") (Nissan and SDRC together being
called the "Seller") and Mechanical Dynamics, Inc., a corporation organized and
existing under the laws of the State of Michigan, U.S.A. and having its
principal place of business at 2301 Commonwealth Boulevard, Ann Arbor, Michigan
48150, U.S.A. (the "Buyer").

                                   WITNESSETH

WHEREAS, Estech Corporation, a corporation organized and existing under the laws
of Japan and having its principal place of business at 89-1, Yamashita-cho,
Naka-ku, Yokohama-shi, Kanagawa-ken, Japan (the "Company"), is engaged in
mechanical engineering consulting services through analysis, computer simulation
and testing to be provided to the several industries, including, but not limited
to, the automobile industries;

WHEREAS, the Buyer is willing to acquire the ownership of the Company;

WHEREAS, the Seller is willing to transfer to the Buyer their combined 100%
ownership of the Company by selling the entire issued share capital of the
Company owned by the Seller;

WHEREAS, the parties hereto, upon execution of the Confidentiality Agreement
dated October 28, 1999 (the "Confidential Agreement"), have engaged in a series
of discussions and negotiations concerning the transfer of the shares in the
Company from the Seller to the Buyer;

WHEREAS, the Buyer has conducted certain due diligence investigations concerning
the Company, its assets and the Business, including, without limitation, the
Company's financial, accounting, legal, regulatory and environmental matters;
and

WHEREAS, the Buyer desires to purchase from the Seller, and the Seller desires
to sell to the Buyer, all of the Shares in exchange for the Purchase Price upon
the terms and subject to the conditions of this Agreement.

NOW, THEREFORE, in consideration of the premises and mutual covenants,
agreements, representations and warranties herein contained, the parties hereto
agree as follows:

ARTICLE 1. DEFINITIONS.

For convenience and brevity, certain terms used in this Agreement are defined or
referred to below (such terms to be equally applicable to both singular and
plural forms of the terms defined). "Acquisition" means the transactions
contemplated in this Agreement.
"Adjustment Amount" is defined in Section 2.2.
"Adjusted Purchase Price" is defined in Section 2.2.
"Agreement" means this Share Transfer Agreement.
"Business" means the existing business, operations, facilities and other
           Assets, financial condition, results of operations, finances,
           markets, products, competitive position, raw materials and other
           supplies, customers and customer relations and personnel of the
           Company.
"Business Day" means any calendar day which is not a Saturday, Sunday or public
           holiday in the place concerned.
"Claim Notice" is defined in Section 10.2(a).
"Closing" and "Closing Date" are defined in Section 3.1.
"Closing Balance Sheet" is defined in Section 2.2.
"Confidential Agreement" is defined in the preamble hereof.

                                       6

<PAGE>   3

"Contract" means any written or oral contract, agreement, lease, plan,
           instrument or other document, commitment, arrangement, undertaking or
           authorization that is or may be binding on any person or its property
           under applicable law.
"Court Order" means any judgment, decree, injunction, order or ruling of any
           court or governmental or regulatory body or authority that is binding
           on any person or its property under applicable law.
"Default" means (i) a breach of or default under any Contract, (ii) the
           occurrence of an event that with the passage of time or the giving of
           notice or both would constitute a breach of or default under any
           Contract or (iii) the occurrence of an event that with or without the
           passage of time or the giving of notice or both would give rise to a
           right of termination, renegotiation or acceleration under any
           Contract.
"Employees" is defined in Section 5.13.
"Employee Adjustment Amount" is defined in Section 4.1(b).
"Guaranty Period" is defined in Section 4.1(b).
"Initial Balance Sheet" is defined in Section 2.2.
"Intellectual Property" is defined in Section 5.11.
"Leases" is defined in Section 5.10.
"Liability" means any liability, indebtedness, obligation, claim, deficiency,
           guaranty or undertaking of or by any person (other than endorsements
           of notes, bills and checks presented to banks for collection or
           deposit in the ordinary course of business) of any type, whether
           accrued, absolute, contingent, matured, unmatured or other.
"License" means licenses, franchises, permits and other similar authorizations.
"Lien" means any mortgage, lien, security interest, pledge, restriction on
           transferability, defect of title, charge or claim of any nature
           whatsoever on any property or property interest.
"Litigation" means any lawsuit, action, arbitration, administrative or other
           proceeding, criminal prosecution or governmental investigation or
           inquiry, other than the investigations or inquiries which are
           conducted by governmental bodies on a regular basis, involving or
           affecting the Company, the Business or any Contracts to which the
           Company is a party or by which it or the Business may be bound or
           affected.
"Material Contracts" is defined in Section 5.12.
"Notice Period" is defined in Section 10.2(a).
"Policies" is defined in Section 5.14.
"Purchase Price" means the aggregate amount of seven hundred eighty-three
           million Yen (Yen 783,000,000), subject to adjustment as provided in
           Section 2.2.
"Regulation" means any statute, law, ordinance, regulation, order or rule of any
           governmental or regulatory body, including, without limitation, those
           covering environmental, energy, safety, health, transportation,
           bribery, record keeping, zoning, antidiscrimination, antitrust, wage
           and hour, and price and wage control matters.
"Seconded Employees" is defined in Section 4.1.
"Seconded Employee Subsidy" is defined in Section 4.1.
"Shares" means five thousand (5,000) ordinary shares of Yen 50,000 each of the
           Company which together represents the entire issued share capital of
           the Company and all of which are fully paid.
"Subsidy Period" is defined in Section 4.1(c).

ARTICLE 2. SALE AND PURCHASE OF THE SHARES.

2.1.       Sale and Purchase of the Shares. Subject to the terms and conditions
           hereinafter set forth and on the basis of and in reliance upon the
           representations, warranties, covenants and agreements set forth
           herein, at the Closing Nissan and SDRC shall each sell to the Buyer
           and the Buyer shall purchase from Nissan and SDRC all of the shares
           in the Company owned by them in exchange for the payment to Nissan
           and SDRC of an amount equal to the Purchase Price, as adjusted
           pursuant to Section 2.2.
2.2.       Adjustment to Purchase Price.  The Purchase Price of Yen 783,000,000
           shall be subject to adjustment (the "Adjustment Amount") by an amount
           equal to the difference between shareholder equity as shown on the
           Company's balance sheet as of March 31, 2000 (the "Initial Balance
           Sheet"), and shareholder equity as shown on the Company's balance
           sheet as of November 30, 2000 (the "Closing Balance Sheet").  The
           Closing Balance Sheet shall be prepared in accordance with generally
           accepted Japanese accounting principals consistently applied.
           Nissan, in conjunction with SDRC, shall use its best efforts to
           cause the Company to prepare and deliver to Nissan, SDRC and Buyer
           the Closing Balance Sheet at the earliest

                                       7

<PAGE>   4

           possible date subsequent to November 30, 2000, but in no event later
           than December 15, 2000. The Adjustment Amount shall be added to or
           subtracted from the Purchase Price of Yen 783,000,000 as the case may
           be (the "Adjusted Purchase Price"). A true and correct copy of the
           Initial Balance Sheet is attached hereto as Exhibit A.

ARTICLE 3. CLOSING.

3.1.       Closing Date. The closing of the sale and purchase of the Shares (the
           "Closing") shall take place at the principal office of Nissan, in
           Tokyo, Japan, on Monday, December 18, 2000, or at such other place or
           on such other date as the Seller and the Buyer may agree to in
           writing. The date of the Closing is hereinafter sometimes referred to
           as the "Closing Date".
3.2.       Closing.
           (a)   At the Closing, subject to the provisions of this Agreement,
                 Nissan and SDRC shall deliver to the Buyer, free and clear of
                 all Liens, the certificates representing their respective
                 shares with the Company's endorsement for confirmation of the
                 transfer of the Shares, in exchange for the full payment by the
                 Buyer to the Seller of the Adjusted Purchase Price which shall
                 be paid to the respective bank accounts designated by Nissan
                 and SDRC in the proportions of seventy percent (70%) to Nissan
                 and thirty percent (30%) to SDRC. Among the Adjusted Purchase
                 Price, 70% proportion thereof payable to Nissan shall be in
                 Japanese Yen, and 30% proportion thereof payable to SDRC shall
                 be in U.S. dollars based on the conversion rate printed in the
                 Wall Street Journal the day the Share Transfer Agreement is
                 executed.
           (b)   At the Closing, the Seller shall make available to the Buyer
                 the written resignations of the directors and statutory
                 auditors of the Company, as separately agreed in writing
                 between Seller and Buyer, effective as of the Closing Date.
           (c)   At the Closing, Nissan and SDRC, as the case may be, shall also
                 deliver to the Buyer, and the Buyer shall deliver to the
                 Seller, the certificates and other instruments and documents
                 referred to in Articles 7, 8, 11 and 12 hereof.
3.3.       Termination.  In the event that the Closing shall not have taken
           place on or before December 29, 2000, all of the rights and
           obligations of the parties under this Agreement shall terminate
           without liability unless otherwise agreed to in writing between the
           Seller and the Buyer; provided, however, that if the failure to meet
           the Closing is caused by reason of a default or breach by any party
           hereto, such party shall be liable for any damages arising out of the
           termination of this Agreement. A default or breach by SDRC shall not
           be deemed a default or breach by Nissan nor shall a default or breach
           by Nissan be deemed a breach or default by SDRC, even if the
           obligation breached is that of Seller.

ARTICLE 4. POST-CLOSING OBLIGATION OF NISSAN.

4.1.       Seconded Employees.  Seller and Buyer acknowledge that certain
           employees currently working for the Company are Nissan employees
           seconded to the Company ("Seconded Employees"). Seller and Buyer
           further acknowledge that Nissan currently is responsible for and pays
           i) in case for those who is in the managerial position, an amount
           equal to twenty percent (20%) of, and ii) in case for those who is in
           the non-managerial position with fifty (50) years of age or older, an
           amount equal to ten percent (10%) of, the salary, bonus, cost of
           social insurance and retirement allowance for each of the subject
           Seconded Employee, together with the board subsidies, (a "Seconded
           Employee Subsidy"). To further induce Buyer to purchase the Shares
           hereunder, Nissan, but not SDRC, agrees with Buyer as follows:
           (a)   Nissan will use its best efforts to encourage Seconded
                 Employees, to the extent permissible under the applicable law,
                 to remain as employees of the Company; and
           (b)   For each Seconded Employee who terminates his or her employment
                 with the Company and returns to Nissan during the ninety (90)
                 day period commencing the Closing Date (the "Guaranty Period"),
                 Nissan will pay to Buyer an additional sum of Yen 10,000,000
                 per such Employee (the "Employee Adjustment Amount"). Buyer
                 will promptly notify Nissan in writing of the termination date
                 of each Seconded Employee who leaves the employ of the Company
                 during the Guaranty Period. The aggregate Employee Adjustment
                 Amount due from Nissan to Buyer hereunder shall be paid by
                 Nissan to Buyer within fifteen (15) days from the end of the
                 Guaranty Period; and

                                       8

<PAGE>   5

           (c)   For the period commencing the Closing Date and ending March 31,
                 2001 (the "Subsidy Period"), Nissan will pay to the Company at
                 such intervals as employees of the Company are paid, an amount
                 equal to the Seconded Employee Subsidy for each Seconded
                 Employee who remains as the Seconded Employee during any
                 portion of the Subsidy Period. Subject to the consents of each
                 employees concerned and labor union to which they belong, the
                 Seconded Employee are assumed to be remained at the Company
                 with the current status as the Seconded Employee by March 31,
                 2001.

ARTICLE 5. REPRESENTATIONS AND WARRANTIES OF NISSAN AND SDRC.

Each of the Seller hereby represents and warrants to the Buyer as specifically
set forth in this Article 5. Each such representation and warranty is true as of
the date of this Agreement, and shall be true in all material respects as of the
Closing Date with the same effect as though such representations and warranties
had been made on and as of the Closing Date (except that representations and
warranties that are made as of specific date need to be true only as of such
date).
5.1.       Seller's Organization and Standing.  Nissan represents and warrants
           that it is a corporation duly organized and validly existing under
           the laws of Japan. SDRC represents and warrants that it is a
           corporation duly organized and validly existing under the laws of the
           State of Ohio, U.S.A.
5.2.       Authority and Binding Effect.  Nissan and SDRC represent and warrant,
           but only with respect to themselves and not the other Seller, that
           (i) it has full corporate power and authority to execute, deliver and
           perform this Agreement and has taken all actions necessary to secure
           all approvals required in connection therewith, (ii) the execution,
           delivery and performance of this Agreement by it has been duly
           authorized by all necessary corporation action, (iii) each person
           signing this Agreement on behalf of it has been duly authorized to do
           so by all necessary corporate action and has the power and authority
           to execute this Agreement on behalf of it, and (iv) this Agreement
           constitutes the legal, valid and binding obligation of it,
           enforceable against it in accordance with its terms, except that the
           enforcement thereof may be limited by bankruptcy, insolvency,
           reorganization or other similar laws affecting the enforcement of
           creditors' rights generally.
5.3.       Validity of Contemplated Transactions.  Neither the execution and
           delivery of this Agreement by the Seller nor the consummation of the
           transactions contemplated hereby will contravene or violate any
           Regulation or Court Order which is applicable to the Seller, the
           Company, or the articles of incorporation or by-laws or their
           equivalents of the Seller or the Company, or will result in a Default
           under, or require the consent or approval of any party to, any
           Contract relating to the Business or to or by which the Seller or the
           Company is a party or otherwise bound or affected, or require the
           Seller or the Company to notify or obtain any License from any court
           or governmental or regulatory body, except that for violations or
           conflicts which give no material influence or cannot give any
           material influence or violations or conflicts which do not
           substantially deprive the Seller of its ability to perform its
           obligation hereunder.
5.4.       Capital Structure and Share Ownership of the Company.
           (a)   The Company's authorized share capital consists of twenty
                 thousand (20,000) ordinary shares, of which total five thousand
                 (5,000) Shares of fifty thousand Yen (Yen 50,000) each have
                 been validly issued are fully paid and nonassessable. Three
                 thousand five hundred (3,500) Shares are registered in the name
                 of Nissan and one thousand five hundred (1,500) Shares are
                 registered in the name of SDRC. All of such shares are
                 beneficially owned by the Seller, free and clear of any Liens.
            (b)  There are and have been (i) no other class or series of any
                 capital shares or other securities of the Company, whether or
                 not presently authorized, issued or outstanding, (ii) no
                 Contracts, subscriptions, options, warrants, calls,
                 commitments, privileges or rights of any character to purchase
                 or otherwise acquire any capital shares or other securities of
                 the Company, whether or not presently authorized, issued or
                 outstanding, from the Seller or the Company, at any time, or
                 upon the happening of any stated event, (iii) no outstanding
                 securities of the Seller or the Company that are convertible
                 into or exchangeable for capital shares or other securities of
                 the Company and (iv) no Contracts, subscriptions, options,
                 warrants, calls, commitments, privileges or rights to purchase
                 or otherwise acquire from the Seller or the Company any such
                 convertible or exchangeable securities.
           (c)   The Company has no subsidiaries nor any ownership interest in
                 any other entity.
5.5.       Title to Shares. Each of the Seller has the right and ability to sell
           and transfer the Shares to the Buyer. The certificates representing
           the Shares have been executed by a duly authorized officer of the
           Company

                                       9

<PAGE>   6

           and are in the Seller's possession. The Seller's ownership of the
           Shares is registered in the Company's register of shareholders
           located at the principal office of the Company. No approvals or other
           actions by the Company are necessary for the sale and transfer of the
           Shares by the Seller to the Buyer, except for the approval of the
           Company's board of directors, the registration of such transfer in
           the Company's register of shareholders and exchange of share
           certificates.
5.6.       Financial Statements.
           (a)   The Seller has delivered, or has caused the Company to deliver,
                 to the Buyer true and complete copies of (i) the Company's
                 Initial Balance Sheet, (ii) the Company's profit and loss
                 statement for the fiscal year ended on March 31, 2000, (iii)
                 the Company's balance sheets dated August 31, 2000, and
                 September 30, 2000, respectively, (iv) the Company's profit and
                 loss statements for the five month period ended August 31,
                 2000, and for the six month period ended September 30, 2000 and
                 (v) all related notes and schedules.
           (b)   To the best of the Seller's knowledge, there has been no
                 material adverse change in the financial conditions of the
                 Company since March 31, 2000, to the date of this Agreement.
                 Further, the Initial Balance Sheet and the other financial
                 statements referred to in (a) above have been, and the Closing
                 Balance Sheet will be, prepared in accordance with generally
                 accepted Japanese accounting principles consistently applied.
5.7.       Books of Account. The books of account of the Company fairly
           reflects, in accordance with generally accepted Japanese accounting
           principles consistently applied, (i) all transactions relating to the
           Company and (ii) all items of income and expense, assets and
           liabilities and accruals relating to the Company.
5.8.       Litigation; Claims. Except as disclosed in writing to the Buyer,
           there is no Litigation pending or, to the best knowledge of the
           Seller, threatened against the Company, its assets or the Business.
           No claim has been asserted and no event has occurred that would, in
           the Seller's reasonable belief, result in a claim or Litigation
           against the Company, its assets or the Business.
5.9.       Assets. The Company has, and at the Closing Date, the Company will
           have, good and unencumbered and marketable title to all of its
           tangible assets as reflected on the Closing Balance Sheet, except for
           dispositions made prior to Closing in the ordinary course of
           business, free and clear of all security interests, mortgages, liens,
           pledges or encumbrances of any kind. Schedule 5.9 to this Agreement
           lists all current customers of the Company and all former customers
           of the Company with whom the Company has done business during the
           past three (3) years.
5.10.      Leases. Schedule 5.10 to this Agreement lists all leases for real
           estate and personal property to which the Company is a party
           ("Leases"). The Seller has delivered to the Buyer a true and complete
           copy of each Lease. All the Leases are valid and binding obligations
           of the parties thereto and no event of default exists under any Lease
           nor does any condition exist which after the passage of time or
           otherwise would allow any party to any Lease to declare an event of
           default thereunder.
5.11.      Intellectual Property. Schedule 5.11 to this Agreement lists all of
           the Company's intellectual property, software programs, including
           without limitation, the software programs known as "Estech Nasdas"
           and "Estech Ride", trademarks, service marks, copyrights and patents
           ("Intellectual Property"). Except as otherwise indicated on said
           Schedule 5.11, the Company is the sole and exclusive owner of all
           Intellectual Property, including without limitation, all rights to
           the source code and the object code of all software listed on said
           Schedule. There have been no claims and to the knowledge of Seller,
           there is no basis for any claim, challenging the scope, validity,
           ownership or enforceability of any of the Intellectual Property. To
           the best of the Seller's knowledge, no claim has been made that the
           Intellectual Property or any activity of the Company infringes upon
           the proprietary rights of any third party or that any activity of any
           third party infringes upon the Intellectual Property of the Company.
5.12.      Agreements and Contracts. Schedule 5.12 to this Agreement lists all
           of the current agreements, contracts, licenses, arrangements,
           understandings and commitments, written or otherwise, to which the
           Company is a party or as to which the Company has any liabilities or
           obligations providing for payments to or liabilities of the Company,
           including any agreement(s) between the Company and Nissan and between
           the Company and SDRC (collectively, the "Material Contracts"). With
           respect to the Material Contracts:
           (a)   all of the Material Contracts are valid and binding obligations
                 of the parties thereto in accordance with their respective
                 terms and there has occurred no event which would constitute a
                 breach of or default by the Material Company or any other party
                 under any of such Material Contracts; and
           (b)   each Material Contract will remain in full force and effect,
                 without any restriction, limitation, cost, penalty or consent,
                 notwithstanding the acquisition of the Shares by Buyer
                 hereunder; and
           (c)   Seller has heretofore delivered to Buyer true and complete
                 copies of each written Material Contract.

                                       10

<PAGE>   7

5.13.      Employees; Employee Benefits. The Seller has delivered, or has caused
           the Company to deliver, to the Buyer true and complete list
           concerning all of the employees of the Company ("Employees") as of
           the date of this Agreement with specific description of all Seconded
           Employees. Said list also includes the age, date of hire, position,
           total amount of salary and bonus which has been actually paid during
           the period from April 2000 through October 2000 of each such
           Employee. No Employee of the Company has any employment agreement or
           other arrangement with the Company except as disclosed in said list.
           All accrued Employee benefits and liabilities are shown on the
           Initial Balance Sheet and will be shown on the Closing Balance Sheet
           in accordance with generally accepted Japanese accounting principles
           consistently applied.
5.14.      Insurance. Schedule 5.14 to this Agreement contains a true and
           complete list of all insurance policies owned or held by the Company
           ("Policies") and sets forth the type and extent of coverage for each
           such Policy. All Policies are in full force and effect. All premiums
           with respect thereto covering all periods up to and including the
           Closing Date have been paid and no notice of cancellation or
           termination has been received by the Company with respect to any
           Policy. Such Policies are sufficient for compliance with all
           requirements of law and all agreements to which the Company is a
           party, are valid and enforceable and will remain in full force and
           effect through the Closing Date without the payment of additional
           premiums. No claims under any current or former insurance policy are
           currently pending.
 5.15.     Undisclosed Liabilities. As of the date of the Initial Balance Sheet,
           there were, and as of the date of the Closing Balance Sheet, there
           will be no liabilities or obligations of the Company of any kind or
           nature whatsoever which have not been adequately reflected and/or
           disclosed on such Balance Sheets. Since the date of the Closing
           Balance Sheet, there will have been no liabilities or obligations
           incurred outside of the usual and ordinary course of business of the
           Company. The Company has not guaranteed any debt or obligation of any
           third party. The Company does not currently engage in "design
           activities" and has not in the past engaged in such "design
           activities" for Nissan or any other customer which could give rise to
           a claim that the Company has partial design responsibility for any
           product.
 5.16.     Taxes. The Company has prepared and timely filed all tax returns and
           reports required by law and all taxes shown thereon to be due have
           been timely paid in full.
 5.17.     Accounts Receivable. The amounts shown as accounts receivable on the
           Closing Balance Sheet will be accurate in all respects and determined
           in accordance with generally accepted Japanese accounting principals
           consistently applied. To the best of the Seller's knowledge, all of
           such accounts receivable will have arisen in the ordinary course of
           the Company's business and are valid and collectible in the ordinary
           course and not subject to any counter claims or set offs.
 5.18.     Compliance With Law. The Company has complied, in all material
           respects, with all applicable laws, regulations, orders and other
           requirements of governmental authorities and the Company has not
           received any notice of violation of any applicable law or regulation
           relating to its assets or Business. Further, the Company is currently
           in compliance, in all material respects, with all applicable
           environmental laws and has never violated any applicable
           environmental law and has not received any notice of noncompliance
           with any environmental law in connection with the operation of its
           Business.
 5.19.     Bank Accounts. Schedule 5.19 to this Agreement sets forth a full and
           complete list of all of the Company's bank accounts and the names of
           the persons authorized to draw thereon.
 5.20.     Absence of Changes or Events. Subsequent to March 31, 2000, and to
           the Closing Date:
           (a)   There have not been any material adverse changes, either
                 individually or in the business, properties or results of
                 operations of the Company;
           (b)   The business affairs of the Company have been conducted in the
                 same manner as theretofore conducted and in the usual and
                 ordinary course;
           (c)   No transaction or material contract has been entered into by
                 the Company, other than in the usual and ordinary course of
                 business;
           (d)   There has been no casualty affecting the Company or loss,
                 damage or destruction to any of its properties, whether or not
                 covered by or compensated under any insurance policy of the
                 Company;
           (e)   The Company has not declared or paid any dividend or other
                 distribution in respect to the capital stock of the Company;
           (f)   The Company has not created, incurred or assumed, or committed
                 to create, incur or assume, any indebtedness or other
                 liability, except for accounts payable or other current
                 liabilities which (i) are not for borrowed money, (ii) were
                 incurred in the usual and ordinary course of business, and
                 (iii) have not been and will not be adverse to the business,
                 properties or results of operations of the Company;

                                       11

<PAGE>   8

           (g)   The Company has not mortgaged, pledged or otherwise encumbered
                 any of its assets;
           (h)   The Company has not varied insurance coverage;
           (i)   The Company has not altered or amended its Articles of
                 Incorporation or Bylaws; and
           (j)   No changes have been made to the accounting practices used by
                 the Company, except for changes required under the generally
                 accepted Japanese accounting principles.

ARTICLE 6. REPRESENTATIONS AND WARRANTIES OF THE BUYER.

The Buyer hereby represents and warrants to each of the Seller as set forth in
this Article 6. Each such representation and warranty is true as of the date of
this Agreement, and shall be true in all material respects as of the Closing
Date with the same effect as though such representations and warranties had been
made on and as of the Closing Date (except that representations and warranties
that are made as of specific date need to be true only as of such date).
6.1.       Buyer's Organization and Standing. The Buyer is a corporation duly
           organized and validly existing under the laws of the State of
           Michigan, U.S.A.
6.2.       Authority and Binding Effect. The Buyer has full corporate power and
           authority to execute, deliver and perform this Agreement and has
           taken all actions necessary to secure all approvals required in
           connection therewith. The execution, delivery and performance of this
           Agreement by the Buyer has been duly authorized by all necessary
           corporation action. Each person signing this Agreement on behalf of
           the Buyer has been duly authorized to do so by all necessary
           corporate action and has the power and authority to execute this
           Agreement on behalf of the Buyer. This Agreement constitutes the
           legal, valid and binding obligation of the Buyer, enforceable against
           it in accordance with its terms, except that the enforcement thereof
           may be limited by bankruptcy, insolvency, reorganization or other
           similar laws affecting the enforcement of creditors' rights
           generally.
6.3.       Validity of Contemplated Transactions. Neither the execution and
           delivery of this Agreement by the Buyer nor the consummation of the
           transactions contemplated hereby by the Buyer will contravene or
           violate any Regulation or Court Order which is applicable to the
           Buyer, or the articles of incorporation or by-laws of the Buyer, or
           will result in a Default under, or require the consent or approval of
           any party to, any Contract to which the Buyer is a party or by which
           it is otherwise bound or affected, or require the Buyer to notify or
           obtain a License from any court or governmental or regulatory body
           except that for violations or conflicts which give no material
           influence or cannot give any material influence or violations or
           conflicts which do not substantially deprive the Buyer of its ability
           to perform its obligation hereunder.
6.4.       Due Diligence Investigation. As of the date of this Agreement, the
           Buyer has conducted and completed its due diligence investigation on
           the Company and the Business, except that Buyer will conduct
           additional interviews with the employees of the Company as it deems
           necessary.
6.5.       No Knowledge of Default. As of the date of this Agreement, the Buyer
           has no knowledge of any default by Seller.

ARTICLE 7. SELLER'S COVENANTS.

7.1.       Covenants. From the date hereof until the Closing Date, except as may
           be approved by the Buyer or as  otherwise expressly provided
           in this Agreement, the Seller shall cause the Company to:
           (a)   operate the Business only in the ordinary course and in
                 substantially the same manner as it has been operated in the
                 past and not sell any of its material assets except for sales
                 from inventory in the ordinary course of business;
           (b)   not issue, repurchase or redeem or commit to issue, repurchase
                 or redeem, any shares of its capital stock, any options or
                 other rights to acquire such stock or any securities
                 convertible into or exchangeable for such stock;
           (c)   not declare or pay any dividend on, or make any other
                 distribution with respect to, the Shares; and
           (d)   not (i) incur any amount of long or short-term debt for money
                 borrowed, (ii) guarantee or agree to guarantee the obligations
                 of others, (iii) indemnify or agree to indemnify others or (iv)
                 incur any other Liabilities other than those incurred in the
                 ordinary course of business consistent with past practice.

                                       12

<PAGE>   9

7.2.       Other Agreements. At or prior to the Closing, Nissan and SDRC agree
           to terminate the Joint Venture Agreement dated March 18, 1994,
           between them and to certify such termination to Buyer at Closing.

ARTICLE 8. BUYER'S COVENANTS.

8.1.       Covenants. The Buyer covenants with and undertakes to the Seller as
           follows:
           (a)   The Buyer shall, within one (1) month from the date of its
                 receipt of all the resignation documents as referred to in
                 Section 3.2(b) above, elect new directors and statutory
                 auditors of the Company, with whom such personnel to be
                 resigned as referred to in Section 3.2(b) shall be replaced,
                 and register thereof with the local Legal Affairs Bureau;
           (b)   Provided that the full liability for such payments (except for
                 the meritorious service reward) is reflected on the Closing
                 Balance Sheet, the Buyer shall cause the Company to pay to the
                 directors and statutory auditors of the Company to be resigned
                 as referred to in Section 3.2(b) above, upon his or her
                 resignation from the Company, one hundred percent (100%) of the
                 applicable retirement allowance under the rules of the Company
                 as of the date of this Agreement; and
           (c)   The Buyer shall not hire or otherwise solicit any of the
                 Company's former employees who quit or resigned the Company
                 within six (6) months prior to the Closing Date.

ARTICLE 9. SURVIVAL OF REPRESENTATION AND WARRANTIES.

All of the representations, warranties, covenants and agreements made by each
party under this Agreement or in any attachment, certificate, document or list
delivered by any such party pursuant hereto or in connection with the
Acquisition shall survive one (1) year from the Closing Date and each party
hereto shall be entitled to rely upon the representations and warranties of the
other party set forth in this Agreement.

ARTICLE 10. INDEMNIFICATION.

10.1.      Indemnification Obligations.  SDRC and/or Nissan (i) proportionally
           in 30% (for SDRC): 70% (for Nissan) basis, not jointly and severally
           to the extent they each are responsible, and (ii) SDRC or Nissan to
           the extent only one shall have committed an indemnifiable event set
           forth in (i) - (iii) below (one or two "indemnifying party") shall
           indemnify and hold harmless the Buyer, and the Buyer (another
           "indemnifying party") shall indemnify and hold harmless the Seller,
           from, against and in respect of any and all material damages, losses,
           deficiencies, liabilities, costs and expenses resulting from,
           relating to or arising out of any (i) material misrepresentation,
           (ii) material breach of warranty, or (iii) non-fulfillment of any
           material agreement or covenant on the part of such indemnifying party
           or parties hereunder. For purposes of this Section 10.1, the term
           "material" shall mean any matter subject to this Article 10 involving
           Yen 2,700,000 or more.
10.2.      Method of Asserting Claims.  All claims for indemnification under
           this Article 10 shall be asserted and resolved as follows:
          (a)    In the event that any claim or demand for which an indemnifying
                 party would be liable to the indemnified party under Section
                 10.1 above is asserted against or sought to be collected by a
                 third party, the indemnified party shall promptly provide the
                 indemnifying party with notice of such claim or demand (the
                 "Claim Notice"), specifying the nature of such claim or demand
                 and the amount or the estimated amount thereof to the extent
                 then feasible (which estimate shall not be conclusive of the
                 final amount of such claim or demand). The indemnifying party
                 shall have one (1) month from its receipt of the Claim Notice
                 (the "Notice Period") to notify the indemnified party (i)
                 whether or not the indemnifying party disputes all or part of
                 its liability to the indemnified party hereunder with respect
                 to such claim or demand and (ii) whether or not it desires, at
                 its sole cost and expense, to defend the indemnified party
                 against such claim or demand; provided, however, that the
                 indemnified party is hereby authorized prior to and during the
                 Notice Period to file any motion, answer or other pleading
                 necessary or appropriate to protect its interests. If and to
                 the extent that the indemnifying party notifies the indemnified
                 party within the Notice Period that it does not dispute such
                 indemnification liability, all or such part of the
                 indemnification liability shall

                                       13

<PAGE>   10

                 be conclusively deemed to be a liability of the indemnifying
                 party hereunder. If the indemnifying party notifies the
                 indemnified party within the Notice Period that it desires to
                 defend the indemnified party against such claim or demand, it
                 may participate in the defense thereof, at its sole cost and
                 expense. If the indemnifying party participates in the defense
                 of any such claim or demand, the indemnified party shall
                 cooperate in the defense. Irrespective of whether the
                 indemnifying party has participated in the defense or
                 settlement of any such claim or demand as to which it has
                 disputed such indemnification liability, any amount which must
                 be paid as a result of such claim or demand shall, subject to a
                 determination that the disputed liability is covered by these
                 indemnification provisions, be a liability of the indemnifying
                 party hereunder. Neither party shall settle, compromise or
                 discharge any third party claim or demand for which indemnity
                 is required hereunder without the consent of the other such
                 party, which consent shall not be unreasonably withheld.
           (b)   In the event that the indemnified party should have a claim
                 against the indemnifying party hereunder which does not involve
                 a claim or demand being asserted against or sought to be
                 collected from it by a third party, the indemnified party shall
                 promptly send a Claim Notice with respect to such claim to the
                 indemnifying party. If the indemnifying party does not notify
                 the indemnified party within the Notice Period that it disputes
                 such claim, the amount of such claim shall be conclusively
                 deemed a liability of the indemnifying party hereunder.
           (c)   Nothing herein shall be deemed to prevent any indemnified party
                 from making a claim hereunder for potential or contingent
                 claims or demands provided the Claim Notice sets forth the
                 specific basis for any such potential or contingent claim or
                 demand and the estimated amount thereof to the extent then
                 feasible and the indemnified party has reasonable grounds to
                 believe that such a claim or demand will be made.
10.3.      Payment.
           (a)   In the event that any party is required to make any payment
                 under this Article 10, such party shall promptly pay the
                 indemnified party the amount so required. If there should be a
                 dispute as to the amount or manner of determination of any
                 indemnity obligation owed under this Article 10, the party from
                 which indemnification is due shall nevertheless pay when due
                 such portion, if any, of the obligation as shall not be subject
                 to dispute. The difference, if any, between the amount of the
                 obligation ultimately determined as properly payable under this
                 Article 10 and the portion, if any, theretofore paid shall bear
                 interest as provided in Section 10.3(c) below. Upon the payment
                 in full of any claim, either by setoff or otherwise, the party
                 making payment shall be subrogated to the rights of the
                 indemnified party against any person, firm, corporation or
                 other entity with respect to the subject matter of such claim.
           (b)   Each indemnifying party shall make full and immediate payment
                 to the indemnified party of any items as to which the
                 indemnified party is entitled to payment under this Article 10.
           (c)   If all or part of any indemnification obligation under this
                 Agreement is not paid when due, then the indemnifying party
                 shall pay the indemnified party or parties interest on the
                 unpaid amount of the obligation for each day from the date the
                 amount became due until payment in full at the fluctuating rate
                 per annum which at all times shall be the rate of interest with
                 respect to Yen generally charged from time to time by a leading
                 Japanese bank and publicly announced by such bank as its
                 so-called "prime rate."
10.4.      Limitation.  The aggregate maximum amount of indemnification by the
           Seller to the Buyer under this Article 10 and any other
           responsibilities under this Agreement shall be the amount equivalent
           to thirty percent (30%) of the Purchase Price. Seller shall have no
           indemnification obligation except and only to the extent the
           aggregate indemnity obligation under this Article 10 and any other
           responsibilities under this Agreement exceeds Yen 2,700,000.

ARTICLE 11.  CONDITIONS PRECEDENT TO OBLIGATIONS OF THE BUYER.

The obligations of the Buyer under this Agreement to be performed by it in
connection with the Closing are subject to the fulfillment prior to or at the
Closing of each of the following conditions:
11.1.      Nissan's and SDRC's Representations True at Closing.   The
           representations and warranties of Nissan and SDRC contained in this
           Agreement and otherwise made by Nissan and SDRC pursuant to this
           Agreement shall be true and correct as of the Closing Date with the
           same effect as though made as of such time.

                                       14

<PAGE>   11

11.2.      Performance by the Seller. The Seller shall have performed and
           satisfied all agreements, covenants and conditions which it is
           required by this Agreement to perform or satisfy prior to or on the
           Closing Date.
11.3.      Litigation Affecting Closing. No Court Order shall have been issued
           or entered which would be violated by the completion of the
           Acquisition. No person who or which is not a party to this Agreement
           shall have commenced or threatened to commence any Litigation seeking
           to restrain or prohibit, or to obtain substantial damages in
           connection with, this Agreement or the transactions contemplated by
           this Agreement and no Litigation shall be pending or threatened
           against the Company.
11.4.      Material Adverse Changes. From the date hereof to the Closing Date,
           neither the Company not the Business shall have been materially
           adversely affected in any way. There shall be no conditions existing
           or threatened with respect to the Company or the Business that might
           be expected to have a material adverse effect on any of them. The
           Closing Balance Sheet shall confirm the foregoing.
11.5.      Officer's Certificate. The Buyer shall have received a certificate
           from an appropriate officer of the Seller dated the Closing Date
           certifying in such detail as the Buyer may request that each of the
           conditions described in Sections 11.1 through 11.4 has been
           fulfilled.
11.6.      Certified Corporate Documents. The Buyer shall have received copies
           of (a) the Articles of Incorporation and Bylaws of the Company, and
           (b) minutes of a meeting of the Board of Directors of the Company in
           which a resolution is adopted by the Board approving the transfer of
           the Shares from Seller to Buyer in accordance with this Agreement,
           all of which documents shall be certified to be true, accurate and
           complete by the Company as of the Closing Date.
11.7.      Incumbency Certificate. The Buyer shall have received a certificate
           from an appropriate officer of the Seller dated the Closing Date
           certifying to the incumbency of the officers of the Seller signing
           for this Agreement and as to the authenticity of their signatures.
11.8.      Noncompetition Agreement. The Buyer shall have received a
           noncompetition agreement executed by the appropriate officers of both
           Nissan and SDRC, confirming Seller's agreement not to compete with
           Estech, in the form attached hereto as Exhibit B.
11.9.      Other Agreements. Buyer shall have received written confirmation from
           SDRC, signed by an appropriate officer, confirming that the Master
           Software License and Service Agreement dated in 1989 between the
           Company and SDRC remains in full force and effect at the Closing
           Date.
11.10.     Form and Content of Documents. The form and content of all documents,
           certificates and other instruments to be delivered by the Seller
           shall be satisfactory to the Buyer.
11.11.     Completion of Due Diligence. The Buyer shall have been completed and
           to be satisfied with its due diligence prior to the Closing Date.
11.12.     Consents. The Seller or the Company shall have delivered to the Buyer
           all consents required to be obtained in connection with the
           Acquisition in order to avoid a Default under any Contract to or by
           which the Company is a party or may be bound. Each of the foregoing
           must be free from burdensome restrictions and conditions not
           applicable to the Company prior to the date of this Agreement.

ARTICLE 12. CONDITIONS PRECEDENT TO OBLIGATIONS OF THE SELLER.

The obligations of the Seller under this Agreement to be performed by it in
connection with the Closing are subject to the fulfillment prior to or at the
Closing of each of the following conditions:
12.1.      Buyer Representations True at Closing. The representations and
           warranties of the Buyer contained in this Agreement and otherwise
           made by the Buyer pursuant to this Agreement shall be true and
           correct as of the Closing Date with the same effect as though made as
           of such time.
12.2.      Performance by the Buyer. The Buyer shall have performed and
           satisfied all agreements, covenants and conditions which it is
           required by this Agreement to perform or satisfy prior to or on the
           Closing Date.
12.3.      Continued Employment. The Buyer shall have offered on the continued
           employment contract between the Company and its current Employees
           with the terms and conditions of at least as favorable to such
           Employees as the terms and conditions they presently enjoy.
12.4.      Litigation Affecting Closing. No Court Order shall have been issued
           or entered which would be violated by the completion of the
           Acquisition. No person who or which is not a party to this Agreement
           shall have commenced or threatened to commence any Litigation seeking
           to restrain or prohibit, or to obtain substantial damages in
           connection with, this Agreement or the transactions contemplated by
           this Agreement.

                                       15

<PAGE>   12

12.5.      Officer's Certificate. The Seller shall have received a certificate
           from an appropriate officer of the Buyer dated the Closing Date
           certifying in such detail as the Seller may request that each of the
           conditions described in Sections 12.1 through 12.3 has been
           fulfilled.
12.6.      Incumbency Certificate. The Seller shall have received a certificate
           from an appropriate officer of the Buyer dated the Closing Date
           certifying to the incumbency of the officers of the Buyer signing for
           this Agreement and as to the authenticity of their signatures.
12.7.      Form and Content of Documents. The form and content of all documents,
           certificates and other instruments to be delivered by the Buyer shall
           be satisfactory to the Seller.
12.8.      Regulatory Compliance and Approval. The Seller shall be satisfied
           that all approvals required under any Regulations to carry out the
           Acquisition shall have been obtained and that the parties have
           complied with all Regulations applicable to the Acquisition.

ARTICLE 13. TERMINATION.

13.1.      Termination by Mutual Consent. This Agreement may be terminated at
           any time prior to the Closing by mutual consent of the Seller and the
           Buyer.
13.2.      Termination for Breach. Each party may terminate its obligations
           under this Agreement at any time prior to the Closing if the other
           party shall have breached any of their representations, warranties or
           other obligations under this Agreement in any material respect. Such
           termination may be effected by written notice from either the Seller
           or the Buyer, as appropriate, citing the reasons for termination, and
           shall not subject the terminating party to any liability for any
           valid termination.

ARTICLE 14. CONFIDENTIALITY.

14.1.      Confidentiality. The parties hereto acknowledge the confidential
           nature of the existence and contents of this Agreement and the
           information supplied in entering into this Agreement, including those
           supplied during the negotiations for the execution of this Agreement,
           (hereinafter collectively referred to as "Confidential Information")
           and shall not without the prior written consent of the other party to
           communicate or otherwise disclose any part of such Confidential
           Information to any person except:
           (a)   where such Confidential Information becomes public without the
                 failure of the disclosing party;
           (b)   where such disclosure is required by law, regulations or where
                 such disclosure is required by related authorities; or
           (c)   where such disclosure is made to employees or agents of such
                 party to the extent necessary for such employees or agents to
                 perform the duties assigned to them by such party pursuant to
                 this Agreement, provided that such employee or agent shall have
                 agreed to keep such Confidential Information secret and such
                 party shall take such other precautions as may be necessary or
                 appropriate to preserve the confidential or secret nature of
                 such Confidential Information.
14.2.      Notwithstanding the provision as stated in Section 15.4 hereof, the
           parties hereto agree and confirm that the Confidential Agreement
           shall remain in full force and effect.

ARTICLE 15. MISCELLANEOUS.

15.1.      Contents of Agreement. This Agreement may not be amended except by an
           instrument in writing signed by all the parties hereto, and no
           claimed amendment, modification, termination or waiver shall be
           binding unless in writing and signed by the party against whom or
           which such claimed amendment, modification, termination or waiver is
           sought to be enforced.
15.2.      Waiver. Any term or provision of this Agreement may be waived at any
           time by the party entitled to the benefit thereof by a written
           instrument executed by such party.
15.3.      Remedies Not Exclusive. Nothing in this Agreement shall be deemed to
           limit or restrict in any manner other rights or remedies that any
           party may have against any other party under applicable law.
15.4.      Entire Agreement. This Agreement constitutes the entire agreement and
           supersedes all prior agreements and understanding, both written and
           oral, between the parties hereto with respect to the subject matter
           hereof.

                                       16

<PAGE>   13

 15.5.     Severability. Any provision of this Agreement which is invalid or
           unenforceable in any jurisdiction shall be ineffective to the extent
           of such invalidity or unenforceability without invalidating or
           rendering unenforceable the remaining provisions hereof, and any such
           invalidity or unenforceability in any jurisdiction shall not
           invalidate or render unenforceable such provision in any other
           jurisdiction.
 15.6.     No Benefit to Others. Except as specifically contemplated by this
           Agreement, the representations, warranties, covenants and agreements
           contained in this Agreement are for the sole benefit of the parties
           hereto, the Company and its successors and assigns, and they shall
           not be construed as conferring and are not intended to confer any
           rights on any other persons.
 15.7.     Further Assurances. Subject to the provisions hereof, the parties
           hereto shall use their best efforts to take, or cause to be taken,
           such action, to execute and deliver, or cause to be executed and
           delivered, such additional documents and instruments and to do, or
           cause to be done, all things necessary, proper or advisable under the
           provisions of this Agreement and under applicable Regulation to
           consummate and make effective the transactions contemplated by this
           Agreement. In addition, the Buyer shall make the records of the
           Company available to Seller in the event that Seller has a reasonable
           need for such access.
 15.8.     Assignment and Binding Effect. This Agreement may not be assigned
           prior to the Closing by any party hereto without the prior written
           consent of the other party. Subject to the foregoing, all of the
           terms and provisions of this Agreement shall be binding upon and
           inure to the benefit of and be enforceable by the successors and
           assigns of the Seller and by the successors and assigns of the Buyer.
 15.9.     Cost. Each of the Seller and the Buyer shall pay all legal,
           accounting and other fees and expenses which such party incurs in
           connection with this Agreement and the transactions contemplated
           hereby, and none of the expenses of the Seller shall be paid by the
           Company. However, if this Agreement is terminated pursuant to Section
           13.2 or if the failure to satisfy a condition of Closing arises out
           of the breach of any representation, warranty or other obligation
           contained in, pursuant to or under this Agreement, the party
           terminating this Agreement shall be entitled to receive from the
           breaching party the expenses of the terminating party incurred
           between the date of this Agreement and the date of termination.
15.10.     Notices. Any notice, request, demand, waiver, consent, approval or
           other communication which is required or permitted hereunder shall be
           in writing and shall be deemed given only if delivered personally to
           the address set forth below (to the attention of the person
           identified below) or sent by telegram, facsimile or by registered or
           certified mail, postage prepaid, as follows:

         If to Nissan to:
                               Nissan Motor Co., Ltd.
                               17-1, Ginza 6-chome
                               Chuo-ku, Tokyo 104-8023, Japan
                               Tel: (03) 5565-2140
                               Fax: (03) 5565-4834
                               Attn.:       Koji Honda
                                            General Manager, Administration
                                            Department for Affiliated Companies

         If to SDRC to:
                               Structural Dynamics Research Corporation
                               2000 Eastman Drive
                               Milford, Ohio 45150, USA
                               Tel: (513) 576-2401
                               Fax: (513) 576-5696
                               Attn.:       John A. Mongelluzzo
                                            Vice President, Secretary and
                                            General Counsel

         If to the Buyer to:
                               Mechanical Dynamics, Inc.
                               2301 Commonwealth Blvd.
                               Ann Arbor, Michigan 48105, USA
                               Tel: (734) 994-3800
                               Fax:  (734) 994-6418
                               Attn.:       Michael E. Korybalski
                                            Chairman and CEO

                                       17

<PAGE>   14

           or to such other address as the addressee may have specified in a
           notice duly given to the sender and to counsel as provided herein.
           such notice, request, demand, waiver, consent, approval or other
           communication shall be deemed to have given as of the date so
           delivered or received by telegram or facsimile or, if mailed, five
           Business Days have elapsed in the place of the address after the date
           so mailed.
 15.11.    Governing Law. This Agreement shall be governed by and construed in
           accordance with the laws of Japan.
 15.12.    Arbitration. All disputes, controversies or differences which
           may arise between the parties hereto, out of or in relation to or in
           connection with this Agreement shall be finally settled by
           arbitration in Tokyo, Japan by three (3) arbitrators in accordance
           with the Commercial Arbitration Rules of The Japan Commercial
           Arbitration Association. The award rendered by the arbitrators shall
           be final and binding upon the parties hereto.
 15.13.    Headings. All headings are for convenience only and shall in no way
           modify or restrict any of the terms or provisions hereof. Any
           reference in this Agreement to a Section shall be deemed to be a
           reference to a Section of this Agreement unless the context otherwise
           expressly requires.
 15.14.    Schedules and Exhibits. All attachments, Exhibits and the Schedules
           referred to herein are intended to be and hereby are specifically
           made a part of this Agreement.
 15.15.    Counterparts. This Agreement may be executed in three (3) or more
           counterparts, each of which is an original and all of which together
           shall be deemed to be one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by their duly authorized representatives as of the date first written above.

NISSAN MOTOR CO., LTD.

By:                /S/
         -----------------------------------
           Name:     Kuniaki Sasaki
           Title:    Senior Vice President

STRUCTURAL DYNAMICS RESEARCH CORPORATION

By:                /S/
         -----------------------------------
           Name:     John A. Mongelluzzo
           Title:    Vice President, Secretary and General Counsel

MECHANICAL DYNAMICS, INC.

By:                /S/
         -----------------------------------
           Name:     Michael E. Korybalski
           Title:    Chairman and CEO

                                       18

<PAGE>   15

                                    EXHIBIT A
                                       TO
                            SHARE TRANSFER AGREEMENT

                              INITIAL BALANCE SHEET
                                  (SECTION 2.2)

                                       19

<PAGE>   16

                               ESTECH CORPORATION
                                  BALANCE SHEET

<TABLE>
<CAPTION>

                                                      (THOUSANDS OF YEN)
                                                   --------------------------
                                                        March 31, 2000
                                                   --------------------------
<S>                                                <C>

Current Assets
    Cash                                           yen                71,485
    Accounts receivable-trade                                        156,872
    Work in process                                                   25,869
    Supplies                                                             872
    Loans receivable                                                 300,000
    Accounts receivable-other                                          4,407
    Deferred tax assets                                               23,096
    Allowance for doubtful accounts                                   (1,842)
                                                   --------------------------
          Total current assets                                       580,759
Intangibles                                                              655
Investment and Other:
    Long-term prepaid expense                                         10,605
    Deferred tax assets                                               16,946
    Other                                                             59,395
                                                   --------------------------
                                                                      86,946
                                                   --------------------------
                                                   yen               668,360
                                                   ==========================

Current liabilities
    Accrued income tax                             yen                22,942
    Consumption tax payable                                            3,483
    Accrued expense                                                   83,162
    Other current liabilities                                          1,447
                                                   --------------------------
                                                                     111,034
Retirement benefits                                                   32,467
Shareholders' equity
    Common stock                                                     250,000
    Retained earnings                                                274,859
                                                   --------------------------
                                                                     524,859
                                                   --------------------------
                                                   yen               668,360
                                                   ==========================
</TABLE>

                                       20

<PAGE>   17

                                    EXHIBIT B
                                       TO
                            SHARE TRANSFER AGREEMENT

                            NONCOMPETITION AGREEMENT
                                 (SECTION 11.8)

                                       21

<PAGE>   18

                                                        NONCOMPETITION AGREEMENT

I hereby confirm that NISSAN (SDRC) agrees not to establish in Japan, as its
subsidiary company, any legal entities which will have same or similar, in all
material respects, business purpose with the Company as such purpose as of this
date, during the period of three (3) years after the Closing Date.

Date:
           ---------------------

           ---------------------
Name:
Title:
           Nissan Motor Co., Ltd.
           (Structural Dynamics Research Corporation)

                                       22<PAGE>   1
                                                                   EXHIBIT 10.45

LOAN NO. 5200026569

                           SECOND AMENDMENT AGREEMENT
                       AMENDED AND RESTATED LOAN AGREEMENT
                        PROMISSORY NOTE (LINE OF CREDIT)

         This Second Amendment Agreement to Amended and Restated Loan Agreement
and Promissory Note (Line of Credit) ("Amendment") is made this __ day of May,
2000, by and between Standard Federal Bank, a federal savings bank, whose
address is 2600 West Big Beaver Road, Troy, Michigan 48084 (hereinafter referred
to as "Standard Federal"), and McClain Industries, Inc., a Michigan corporation,
McClain E-Z Pack, Inc., a Michigan corporation, McClain Galion, Inc., a Michigan
corporation, Shelby Steel Processing Company, a Michigan corporation, McClain
Tube Company d/b/a Quality Tube, a Michigan corporation, McClain International
FSC, a U.S. Virgin Islands corporation, and McClain Southland Co., a Florida
corporation, each having a mailing address and/or principal office of 6200
Elmridge, Sterling Heights, Michigan 48310 (collectively hereinafter referred to
as "Borrowers").

         WITNESSETH:

         WHEREAS, Borrowers and Standard Federal entered into an Amended and
Restated Loan Agreement dated July 9, 1999, as amended by the First Amendment
Agreement dated February 11, 2000 (the "Loan Agreement");

         WHEREAS, Pursuant to the Loan Agreement, Borrowers executed and
delivered to Standard Federal a Promissory Note (Line of Credit) dated July 9,
1999 in the original principal amount of $35,000,000, as amended by the First
Amendment Agreement dated February 11, 2000 (the "Note");

         WHEREAS, Borrowers and Standard Federal desire to increase the
Revolving Line of Credit from $30,000,000 to $35,000,000 and waive, modify and
amend certain terms, conditions, covenants and obligations contained in the Loan
Agreement and the Note, all effective as of the date hereof unless otherwise
specified to the contrary.

         NOW, THEREFORE, in consideration of the mutual promises, covenants,
modifications and agreements hereinafter made, the parties hereto agree as
follows:

         1.       INCORPORATION BY REFERENCE:

                  All definitions and terms used in the Loan Agreement are
hereby incorporated in this Amendment.

         2.       AMENDMENTS AND MODIFICATIONS TO LOAN AGREEMENT:

                  A.       The first sentence of the definition of "Collateral
Reserve" as defined in Section 1 of

<PAGE>   2

                           the Loan Agreement is hereby deleted in its entirety,
                           and in lieu thereof, the following is inserted:

                           "`Line of Credit Cap' shall mean, initially, Thirty
                           Five Million and 00/100 Dollars ($35,000,000.00). The
                           Line of Credit Cap shall reduce by $714,285.71 on the
                           last day of each month, commencing June 30, 2000 and
                           continuing through December 31, 2000, after which
                           date the Line of Credit Cap shall be Thirty Million
                           and 00/100 Dollars ($30,000,000)."

                  B.       The reference to "3.25" in the second line of Section
10.2.13 on Page 25 of the Loan Agreement is hereby amended to read "3.35."

                  C.       For the financial quarter ending December 31, 1999,
Standard Federal hereby waives the financial covenant stated in Section 10.2.13
on Page 25 of the Loan Agreement.

                  D.       Section 10.2.18 is hereby added to the Loan Agreement
 as follows:

                           "Maintain total funded TRAC leases plus unfunded
                           availability of TRAC leases of not more than
                           $20,000,000. As used in this Section "TRAC" shall
                           mean terminal residual adjustment clause.

         3.       AMENDMENTS AND MODIFICATIONS TO THE NOTE:

                  The principal amount stated in the Note is increased to the
sum of Thirty Five Million and 00/100 Dollars ($35,000,000). Borrowers hereby
promise to pay to the order of Standard Federal on or before May 1, 2002 the
principal amount of the Note and all accrued interest thereon, as hereby
amended, in accordance with the terms of the Note and the Loan Agreement, as
hereby amended.

         4.       SURVIVAL AND REAFFIRMATION:

                  Each signatory hereto, by execution hereof, respectively
agrees for itself, in all capacities in which each signatory has executed the
Loan Agreement or Note as follows:

                  A.       That, except as herein modified or amended, all
terms, conditions, covenants, representations and warranties contained in the
Loan Agreement shall remain in full force and effect, and that the undersigned
hereby consent to and acknowledge the foregoing Amendment hereinabove set forth.

                  B.       That the liability of the undersigned howsoever
arising or provided for in the Loan Agreement and/or the Note, as hereby
modified or amended, is hereby reaffirmed.

                  C.       That each Borrower is in good standing.

                                       2
<PAGE>   3

                  D.       Borrowers hereby represent and warrant that, after
giving effect to the amendments contained herein, (a) execution, delivery and
performance of this Amendment, and any other documents and instruments required
under this Amendment, or the Loan Agreement are within each Borrower's corporate
powers, have been duly authorized, are not in contravention of law or the terms
of any Borrower's Articles of Organization or Bylaws and do not require the
consent or approval of any governmental body, agency or authority; and this
Amendment and any other documents and instruments required under this Amendment,
the Loan Agreement or the Note will be valid and binding in accordance with
their terms; and (b) no Event of Default, or condition or event which, with the
giving of notice or the running of time, or both, would constitute a Event of
Default under the Note, has occurred and is continuing as of the date hereof.

                  E.       The Assignment of Equipment Leases and Security
Agreement dated July 17, 1996, as amended April 28, 1997 ("Security Agreement"),
is valid and enforceable in accordance with its terms. Standard Federal's
security interests in the collateral described in the Security Agreement are
valid and perfected and Borrowers are not aware of any claims or interest in
such collateral proper or paramount to Standard Federal's.

                  F.       The execution of this Amendment shall not be deemed
to be a waiver of any Event of Default.

                  G.       Each Borrower waives, discharges, and forever
releases Standard Federal, Participants, Standard Federal's and Participants'
employees, officers, directors, attorneys, stockholders, and their successors
and assigns, from and of any and all claims, causes of action, allegations or
assertions that any Borrower has or may have had at any time up through and
including the date of this Amendment, against any or all of the foregoing,
regardless of whether any such claims, causes of action, allegations or
assertions are known to any Borrower or whether any such claims, causes of
action, allegations or assertions arose as result of Standard Federal's actions
or omissions in connection with the Note, or any amendments, extensions or
modifications thereto, or Standard Federal's administration of the debt
evidenced by the Note or otherwise.

         This Amendment may be executed in counterparts, each of which shall
constitute an original and all of which shall together constitute one and the
same Amendment.

         IN WITNESS the due execution hereof as of the day and year first above
written.

BANK:                                       BORROWERS:
----                                        ---------

STANDARD FEDERAL BANK,                      MCCLAIN INDUSTRIES, INC.,
A FEDERAL SAVINGS BANK                      A MICHIGAN CORPORATION

By:                                         By:  /s/ Mark S. Mikelait
   -------------------------                   ---------------------------------
Its:                                        Its: Treasurer
    ------------------------                    --------------------------------

                                       3
<PAGE>   4

                                            MCCLAIN E-Z PACK, INC., A
                                            MICHIGAN CORPORATION

                                            By:   /s/ Mark S. Mikelait
                                               ---------------------------------
                                            Its:  TREASURER
                                                --------------------------------

                                            MCCLAIN GALION, INC., A
                                            MICHIGAN CORPORATION

                                            By:   /s/ Mark S. Mikelait
                                               ---------------------------------
                                            Its:  TREASURER
                                                --------------------------------

                                            SHELBY STEEL PROCESSING
                                            COMPANY, A MICHIGAN CORPORATION

                                            By:   /s/ Mark S. Mikelait
                                               ---------------------------------
                                            Its:  TREASURER
                                                --------------------------------

                                            MCCLAIN TUBE COMPANY D/B/A
                                            QUALITY TUBE, A MICHIGAN CORPORATION

                                            By:   /s/ Mark S. Mikelait
                                               ---------------------------------
                                            Its:  TREASURER
                                                --------------------------------

                                            MCCLAIN INTERNATIONAL FSC, A
                                            US VIRGIN ISLANDS CORPORATION

                                            By:   [SIG.]
                                               ---------------------------------
                                            Its:  PRESIDENT
                                                --------------------------------

                                            MCCLAIN SOUTHLAND CO., A
                                            FLORIDA CORPORATION

                                            By:   /s/ Mark S. Mikelait
                                               ---------------------------------
                                            Its:  TREASURER
                                                --------------------------------

                                       4

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00019-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00019-of-00352.parquet"}]]