EXHIBIT 10.85
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                               GUARANTY AGREEMENT
                               ------------------


         THIS GUARANTY AGREEMENT ("Guaranty"), dated as of November 29, 1999, is
made and entered into upon the terms hereinafter set forth by GENERIC
DISTRIBUTORS, INCORPORATED, a Delaware corporation("Guarantor"), in favor of
FINOVA MEZZANINE CAPITAL INC., Tennessee corporation formerly known as SIRROM
CAPITAL CORPORATION ("FMC"), for itself and in its capacity as Collateral Agent
pursuant to that Collateral Agent Agreement dated June 18, 1997, (the "Agency
Agreement") by and between FMC and Argosy Investment Partners, L.P., a
Pennsylvania limited partnership ("Argosy") (FMC and Argosy individually and
collectively referred to herein as "Creditor").


                                    RECITALS:

1. Pursuant to a Loan Agreement dated as of June 18, 1997, by and between
DynaGen, Inc. a Delaware corporation and sole shareholder of Guarantor
("Debtor"), and Creditor (the "Loan Agreement"), Creditor has made loans to
Debtor in the aggregate initial principal amount of $3,000,000 (the "Loans").
The Loans are evidenced by a Secured Promissory Note dated June 18, 1997, in the
original principal amount of $2,000,000 made and executed by Debtor, payable to
the order of FMC ("FMC Note") and a Secured Promissory Note dated June 18, 1997,
in the original principal amount of $1,000,000 made and executed by Debtor,
payable to the order of Argosy ("Argosy Note") (the FMC Note and the Argosy Note
are collectively herein referred to, together with any extensions,
modifications, renewals and/or replacements thereof, including the "Amendment,"
as defined below, as the "Note").

1. Debtor and Creditor desire to enter into that Amendment and Agreement of even
date herewith (the "Amendment") with respect to the Loan and the Loan Agreement.

2. It is a condition of Creditor's execution of the Amendment that Guarantor
execute and deliver this Guaranty to Creditor.

3. Guarantor desires to execute and deliver this Guaranty to Creditor in order
to induce Creditor to enter into the Amendment, which will be to the direct
interest, advantage and benefit of Guarantor.


                                   AGREEMENTS:

         NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged by Guarantor, and to induce Creditor to enter into the Amendment,
Guarantor hereby agrees as follows:

1. Gantor hereby guarantees to Creditor the full and prompt payment and
performance of (a) the indebtedness evidenced by the Note, principal and any and
all interest accrued or to accrue thereon and (b) the obligations of Debtor to
Creditor pursuant to the Note, the Loan Agreement and any and all other
instruments, documents and/or agreements now or hereafter further evidencing,
securing or otherwise related to the indebtedness evidenced by the Note
(collectively, the "Guaranteed Obligations"). Guarantor hereby agrees that if
the Guaranteed Obligations are not timely paid and/or performed, as the case may
be, in accordance with the terms thereof, Guarantor immediately will pay and/or
perform such Guaranteed Obligations. If for any reason any payment or obligation
in respect of the Guaranteed Obligations shall be determined at any time to be a
voidable preference or otherwise shall be set aside or required to be returned
or repaid, this Guaranty nevertheless shall remain in full force and effect and
shall be fully enforceable against Guarantor for the payment or obligation set
aside, returned or repaid, as well as any other Guaranteed Obligations still
outstanding, notwithstanding the fact that this Guaranty may have been canceled,
released and/or returned to Guarantor by Creditor. This Guaranty is irrevocable.
<PAGE>

2. In addition to the obligations of Guarantor to Creditor pursuant to Paragraph
1 hereof, Guarantor further agrees to pay any and all expenses (including
without limitation attorney's fees) reasonably incurred by Creditor in
endeavoring to collect and/or enforce the obligations of Guarantor under this
Guaranty.

3. Guarantor hereby waives notice of any breach or default by Debtor, and hereby
further waives presentment, demand, notice of dishonor and protest with respect
to any instrument now or hereafter evidencing any of the Guaranteed Obligations.

4. Guarantor's guarantee of the Guaranteed Obligations is absolute and
unconditional. The validity of this Guaranty and Guarantor's absolute obligation
to pay hereunder shall not be impaired by any event whatsoever, including, but
not limited to, the financial decline of Debtor; the filing by or against Debtor
of a proceeding under any chapter of the Bankruptcy Code (as used in this
Guaranty, "Debtor" shall include Debtor's reorganizing or liquidating estate in
any bankruptcy proceeding); the merger, consolidation, dissolution, cessation of
business or liquidation of Debtor; the failure of any other party to guarantee
the Guaranteed Obligations or to provide collateral therefor; Creditor's
compromise or settlement with or without release of Debtor or any other party
liable for the Guaranteed Obligations; Creditor's failure to perfect any
security interest in any property now or hereafter intended to secure the
Guaranteed Obligations; Creditor's release of any collateral for the Guaranteed
Obligations; Creditor's failure to file suit against Debtor (regardless of
whether Debtor is becoming insolvent, is believed to be about to leave the
state, or any other circumstance); Creditor's failure to give Guarantor notice
of default by Debtor; the unenforceability of the Guaranteed Obligations against
Debtor, due to bankruptcy discharge, counterclaim or for any other reason;
Creditor's acceleration of the Guaranteed Obligations at any time; the
extension, modification or renewal of the Guaranteed Obligations, with or
without notice to Guarantor; Creditor's failure to undertake or exercise
diligence in collection efforts against any party or property; the termination
of any relationship of Guarantor with Debtor, including, but not limited to, any
relationship of employment, ownership or commerce; Debtor's change of name or
use of any name other than the name used to identify Debtor in this Guaranty;
Debtor's use of the credit extended by Creditor for any purpose whatsoever; or
any other event that might otherwise constitute a legal or equitable discharge
of, or defense available to, a guarantor or surety. All Guaranteed Obligations
arising after the execution hereof shall be deemed incurred by Creditor in
reliance upon the continued operation of this Guaranty and shall constitute
additional consideration for Guarantor's execution of this Guaranty. Guarantor
agrees that this Guaranty shall be valid and binding upon Guarantor upon the
delivery of this executed Guaranty to Creditor by any party whomsoever.

5. Creditor may, in its sole discretion, with or without consideration and with
no impairment of Guarantor's obligations under this Guaranty, release any
collateral securing the Guaranteed Obligations or release any party liable
therefor. Guarantor hereby waives the defenses of impairment of collateral and
impairment of recourse and any requirement of diligence on Creditor's part in
collecting the Guaranteed Obligations.

6. Should the liability of Guarantor hereunder for the entire amount of the
Guaranteed Obligations be subject to avoidance or limitation, notwithstanding
the contrary agreement and intention of Guarantor and Creditor, under any state
or federal fraudulent transfer laws, laws regarding corporate distributions or
other law, then the liability of Guarantor for the Guaranteed Obligations shall
be limited to the maximum amount for which Guarantor may be liable without legal
impairment.

7. Guarantor warrants to Creditor that Guarantor is not insolvent and that
Guarantor's execution hereof does not render Guarantor insolvent for the purpose
of state or federal fraudulent transfer laws or other avoidance laws, laws
regarding corporate distributions or any other law.

8. Guarantor acknowledges and represents that, in connection with Guarantor's
decision to enter into this Guaranty, Guarantor has not relied upon any
financial projection, budget, assessment or other analysis by Creditor or upon
any representation by Creditor as to the risks, benefits or prospects of
Debtor's business activities or present or future capital needs incidental
thereto or the present or future provisions of documents with Debtor that
evidence the Guaranteed Obligations, all such considerations having been
examined fully and independently by Guarantor. Guarantor represents that
Guarantor has made such arrangements as Guarantor desires for the obtaining of
information regarding Debtor, and agrees that Creditor is not obligated to
provide Guarantor with any present or ongoing information about the financial
condition, operations or prospects of Debtor.
<PAGE>

9. If proceedings are instituted by Debtor under any state insolvency law or
under any federal bankruptcy law, or if such proceedings are instituted against
Debtor and are not dismissed within forty-five (45) days, Creditor may, at its
option, without notice and notwithstanding any limitation on Creditor's ability
to use such proceedings as the basis of a default or acceleration against
Debtor, declare all the Guaranteed Obligations presently due and payable by
Guarantor. The term "Debtor," as used in this Guaranty, includes Debtor's estate
in any bankruptcy, reorganization or other debtor relief proceeding.

10. Guarantor's obligation under this Guaranty is independent of any other
obligations among Creditor, Debtor and Guarantor. No setoff, counterclaim,
reduction or diminution of any obligation, or defense of any kind or nature that
Guarantor or Debtor has or may have against Creditor, shall be effective against
Creditor in the enforcement of this Guaranty.

11. Guarantor acknowledges that the terms and conditions of the extension of
credit from Creditor to Debtor are set forth entirely in agreements between
Creditor and Debtor. It shall not be a defense to Guarantor's liability
hereunder if Creditor fails to extend credit to Debtor or accelerates the
Guaranteed Obligations in accordance with the terms and conditions of the
documents between Creditor and Debtor from time to time.

12. Guarantor acknowledges and agrees that the statute of limitation applicable
to this Guaranty shall begin to run only upon Creditor's accrual of a cause of
action against Guarantor hereunder caused by Guarantor's refusal to honor a
demand for performance hereunder made by Creditor in writing; provided, however,
if, subsequent to the demand upon Guarantor, Creditor reaches an agreement with
Debtor on any terms causing Creditor to forbear in the enforcement of its demand
upon Guarantor, the statute of limitation shall be reinstated for its full
duration until Creditor subsequently again makes written demand upon Guarantor.

13. Until all of the covenants, terms and conditions of Debtor with respect to
the Guaranteed Obligations are fully paid, performed, kept and/or observed,
Guarantor: (a) shall have no rights of reimbursement or subrogation against
Debtor of any of its property by reason of any payment or acts of performance by
Guarantor in compliance with the obligations of Guarantor hereunder, (b) waives
any right to enforce any remedy that Guarantor now or hereafter shall have
against Debtor by reason of any one or more payments or acts of performance in
compliance with the obligations of Guarantor hereunder, and subordinates any
liability or indebtedness of Debtor now or hereafter held by Guarantor to the
obligations of Debtor to Creditor under the Guaranteed Obligations.

14. This is a guaranty of payment and performance and not of collection. The
liability of Guarantor hereunder shall be direct and immediate and not
conditional or contingent upon the pursuit of any remedies against Debtor or any
other person, not against any collateral available to Creditor. Guarantor hereby
waives any right to require that an action be brought against Debtor or any
other person or to require that resort be had to any collateral in favor of
Creditor prior to discharging its obligations hereunder. Guarantor further
waives any right of Guarantor to require that an action be brought against
Debtor under the provisions of Title 47, Chapter 12, Tennessee Code Annotated,
as the same may be amended from time to time.

15. Guarantor hereby consents and agrees that all payments and credits received
from Debtor or Guarantor or realized from any collateral may be applied by
Creditor to the Guaranteed Obligations in such priority as Creditor in its sole
judgment shall see fit.

16. This Guaranty shall be construed in accordance with and governed by the laws
of the State of Tennessee applicable to contracts to be performed within said
state. No amendment or modification hereby shall be effective unless evidenced
by a writing signed by Guarantor and Creditor. When used herein, the singular
shall include the plural, and vice versa, and the use of any gender shall
include all other genders, as appropriate.

17. Guarantor hereby waives notice of acceptance of this Guaranty by Creditors.

18. CREDITOR AND GUARANTOR HEREBY WAIVE TRIAL BY JURY IN ANY ACTIONS,
PROCEEDINGS, CLAIMS OR COUNTER-CLAIMS, WHETHER IN CONTRACT OR TORT, AT LAW OR IN
EQUITY, ARISING OUT OF OR IN ANY WAY RELATING TO THIS AGREEMENT.
<PAGE>

19. Guarantor warrants that it is and shall remain a duly organized corporation
in good standing under the laws of the state of its incorporation, and that
Guarantor is and shall remain duly qualified to do business in each state in
which qualification is necessary. Guarantor warrants that its execution and
delivery of and performance under this Guaranty and all related documents are
permitted under and will not violate any provision of Guarantor's Charter or
By-Laws. Guarantor further warrants that the execution of all necessary
resolutions and other prerequisites of corporate action have been duly performed
so that the individual executing this Guaranty and related documents on behalf
of Guarantor is duly authorized to bind Guarantor by his or her signature.

20. Following the occurrence and during the continuation of an Event of Default
under the Loan Agreement, Guarantor covenants to furnish to Creditor, upon
demand, copies of Guarantor's tax returns and additional financial statements in
form and substance acceptable to Creditor in the same manner and form as
required of Debtor in the Loan Agreement.

21. Guarantor warrants and agrees that the recitals set forth at the beginning
of this Guaranty are true.

22. Guarantor warrants that the execution, delivery and performance of this
Guaranty will not violate any judicial or administrative order or governmental
law or regulation, and that this Guaranty is valid, binding and enforceable in
every respect according to its terms.

23. Guarantor warrants that Guarantor's execution, delivery and performance of
this Guaranty do not require the consent of or the giving of notice to any third
party including, but not limited to, any other Creditor, governmental body or
regulatory authority.

24. Guarantor hereby irrevocably consents to the jurisdiction of the United
States District Court for the Middle District of Tennessee and of all Tennessee
state courts sitting in Davidson County, Tennessee, for the purpose of any
litigation to which Creditor may be a party and which concerns this Guaranty or
the Secured Indebtedness. It is further agreed that venue for any such action
shall lie exclusively with courts sitting in Davidson County, Tennessee, unless
Creditor, in its discretion, elects the venue of another appropriate
jurisdiction.

25. Nothing contained herein or in any related document shall be deemed to
render Creditor a partner of Guarantor for any purpose. This Guaranty has been
executed for the sole benefit of Creditor, and no third party is authorized to
rely upon Creditor's rights hereunder or to rely upon an assumption that
Creditor has or will exercise its rights under this Guaranty or under any
document referred to herein.

26. Any notices concerning this Guaranty shall be addressed as follows: As to
Guarantor:

                  GENERIC DISTRIBUTIONS, INCORPORATED
                  Attn: President
                  99 Erie Street
                  Cambridge, Massachusetts 02139
                  Telecopier: 617/354-3902

                  With a copy to:

                  David A. Broadwin
                  Foley, Hoag & Eliot LLP
                  One Post Office Square
                  Boston, Massachusetts 02109
                  Telecopier: 617/248-7100
<PAGE>

                  As to Creditor:

                  FINOVA MEZZANINE CAPITAL INC.
                  Attn: Tim McCarthy
                  Vice President
                  500 Church Street Suite 200
                  Nashville, TN 37219
                  Telecopier: (615) 726-1208

                  With a copy to:

                  Boult, Cummings, Conners & Berry
                  Attn: Roger G. Jones
                  414 Union Street, Suite 1600
                  P.O. Box 198062
                  Nashville, Tennessee  37219
                  Telecopier: (615) 252-2323


Notices shall only be effective when set forth in writing and delivered (by mail
or otherwise) as indicated above. A party may change that party's address for
receipt of notices by submitting the change in writing in accordance with this
Section.

27. Creditor's indulgence in any departure from the terms of this Guaranty or
any other document shall not prejudice Creditor's rights to make demand and
recover from Guarantor in accordance with this Guaranty, or otherwise demand
strict compliance with this Guaranty.

28. The remedies provided Creditor in this Guaranty are not exclusive of any
other remedies that may be available to Creditor under any other document or at
law or equity.

29. This Guaranty shall be binding upon and inure to the benefit of the
respective heirs, successors and assigns of Guarantor and Creditor, except that
Guarantor shall not assign any rights or delegate any obligations arising
hereunder without the prior written consent of Creditor. Any attempted
assignment or delegation by Guarantor without the required prior consent shall
be void.

30. Should any provision of this Guaranty be invalid or unenforceable for any
reason, the remaining provisions hereof shall remain in full effect.

31. Words used herein indicating gender or number shall be read as context may
require.

32. Captions and headings have been included in this Guaranty for the
convenience of the parties, and shall not be construed as affecting the content
of the respective Sections.

33. GUARANTOR AND CREDITOR HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY
PROCEEDING ARISING FROM OR RELATED TO THIS AGREEMENT, WITH THE EFFECT THAT ANY
SUCH MATTER SHALL BE DETERMINED BY A JUDGE AS TO ISSUES OF LAW AND OF FACT.

34. GUARANTOR ACKNOWLEDGES CREDITOR'S INTENTION TO ENFORCE THIS GUARANTY TO THE
FULLEST EXTENT POSSIBLE AND GUARANTOR ACKNOWLEDGES THAT CREDITOR HAS MADE NO
ORAL STATEMENTS TO GUARANTOR THAT COULD BE CONSTRUED AS A WAIVER OF CREDITOR'S
RIGHT TO ENFORCE THIS GUARANTY BY ALL AVAILABLE LEGAL MEANS.

         IN WITNESS WHEREOF, the undersigned Guarantor has executed this
Guaranty, or has caused this Guaranty to be executed by its duly authorized
representative, as of the date first above written.
<PAGE>


                                GENERIC DISTRIBUTORS, INCORPORATED


                                By: /s/ Dhananjay Wadekar
                                    --------------------------
                                Title: Secretary




                                FINOVA MEZZANINE CAPITAL INC., for itself and in
                                its capacity as Agent under the Agency Agreement


                                By: /s/ Tim McCarthy
                                    --------------------------
                                Title: Vice President