EXHIBIT 10.2
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                          REGISTRATION RIGHTS AGREEMENT


           AGREEMENT dated as of May 9, 2001 by and between DynaGen, Inc., a
Delaware corporation (the "Company"), and the Purchaser listed on the execution
page of this Agreement.

                                    ARTICLE I
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                          GRANT OF REGISTRATION RIGHTS
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           1.01. Investment Documents. Pursuant to the Subscription Agreement
dated as of May 9, 2001 (herein, as amended from time to time, called the
"Subscription Agreement"), DynaGen, Inc., a Delaware corporation (the
"Company"), grants to the Purchaser (as defined therein) who is a party thereto,
the registration rights contained in Article II of this Agreement.

           1.02. Definitions. For all purposes of this Agreement, all of the
words and expressions used herein which are not defined herein, but which are
defined in the Subscription Agreement, shall have the same respective meanings
herein as the meanings specified therein.

                                   ARTICLE II

                               REGISTRATION RIGHTS

           2. Registration Rights.

           2.01. Definitions. As used in this Agreement:

           (a) the term "Commission" shall mean the Securities and Exchange
Commission;

           (b) the term "Common Stock" shall mean the Common Stock, par value
$0.01 per share, of the Company or any other security into which the Preferred
Stock may, by its terms, be converted;

           (c) the term "Exchange Act" shall mean the Securities Exchange Act of
1934, as amended, or any federal statute or code which is a successor thereto;

           (d) the term "Form S-3" shall mean the form so designated,
promulgated by the Commission for registration of securities under the
Securities Act, and any forms succeeding to the functions of such form, whether
or not bearing the same designation;

           (e) the term "Holder" shall mean the original Purchaser, and any
person to whom the Preferred Stock is transferred pursuant to the terms of the
Subscription Agreement;

           (f) the terms "register", "registered" and "registration" shall refer
to a registration effected by preparing and filing a registration statement in
compliance with the Securities Act
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and the declaration or ordering by the Commission of effectiveness of such
registration statement;

           (g) the term "Registrable Securities" shall mean, in relation to the
Holder at any particular time: (i) all shares of Common Stock issuable upon
conversion of the Preferred Stock held of record by the Holder at such time;
(ii) all shares of Common Stock held of record at such time by Holder as a
result of such conversion or exercise; and (iii) no other shares of capital
stock of the Company without the consent of the Holder.

           (h) the term "Rule 144" shall mean Rule 144 issued by the Commission
under the Securities Act, or any subsequent rule pertaining to the disposition
of securities without registration;

           (i) the term "Securities Act" shall mean the Securities Act of 1933,
as amended, or any federal statute or code which is a successor thereto;

           (j) the term "Preferred Stock" shall mean the shares of Series P
Convertible Preferred Stock, par value $0.01 per share, of the Company issued to
the original Purchaser pursuant to the Subscription Agreement and any other
Preferred Stock issued to other purchasers;

           (k) the Holder shall, for all purposes of this Agreement, unless the
context shall otherwise require, be deemed to hold, at any particular time, all
shares of Common Stock issuable upon conversion of the Preferred Stock held of
record by the Holder at such time.

           2.02. Registration on Form S-3. The Company will use its best efforts
in good faith to register the Registrable Securities on Form S-3 by February 9,
2002 (regardless of the number of times transfer of such shares is made on the
stock transfer books maintained by or for the Company, and regardless of the
number of certificates which may be issued to evidence such shares, and
irrespective of any subsequent transfer of or the disposition of such shares to
any other holder) (the "Registration Period"). To the extent not unlawful, the
Company will pay all Registration Expenses of each registration of Registrable
Securities pursuant to this Section 2.02. If the Company has not registered the
Registrable Securities by the end of the Registration Period or if the
Registration Statement is not effective at the end of the Permitted Suspension
Period (as hereinafter defined), the Company shall pay to the Holder one percent
(1.0%) of the aggregate purchase price paid by such Holder for the Preferred
Stock for each month that the Registrable Securities are not registered, which
amount shall be pro-rated for partial months, until the earlier of the
registration of the Registrable Securities and the date the Registrable
Securities are eligible for sale under Rule 144, provided, however, the Company
shall not be required to make such payment if the Company's failure to register
the Registrable Securities is due, in whole or in part, to the Holder's failure
to comply with Section 2.04 hereof.

           2.03. Registration Procedures. When the Company undertakes to effect
a registration pursuant to Section 2.02 hereof of the Registrable Securities,
the Company will use its best efforts in good faith to effect promptly the
registration of such Registrable Securities under the Securities Act and to
permit the public offering and sale of such Registrable Securities in

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accordance with the intended method of disposition thereof, and, in connection
therewith, the Company, as expeditiously as shall be reasonably possible, will:

           (a) prepare and file with the Commission a registration statement
with respect to such Registrable Securities, and use its best efforts in good
faith to cause such registration statement to become and remain effective as
provided herein;

           (b) prepare and file with the Commission such amendments and
supplements to such registration statement and the prospectus included in such
registration statement as may be necessary or advisable to comply in all
material respects with the provisions of the Securities Act with respect to the
disposition of all securities covered by such registration statement or as may
be necessary to keep such registration statement effective and current, but for
no longer than one (1) year subsequent to the effective date of such
registration;

           (c) furnish to each seller of Registrable Securities such number of
copies of such registration statement, each amendment and supplement thereto (in
each case including all exhibits thereto), the prospectus included in such
registration statement (including each preliminary prospectus), and such other
documents as any such seller may reasonably request in order to facilitate the
disposition of the Registrable Securities held by such seller;

           (d) enter into such customary agreements and take all such other
customary action in connection therewith in order to expedite or facilitate the
disposition of such Registrable Securities; and

           (e) use its best efforts in good faith to register and qualify the
Registrable Securities covered by such registration statement under such
securities or Blue Sky laws of such jurisdictions as any seller shall reasonably
request and do any and all such other acts and things as may be reasonably
necessary or advisable to enable such seller to consummate the disposition in
such jurisdictions of the Registrable Securities held by such seller; provided,
however that the Company shall not be required in connection therewith to
qualify to do business or file a general consent to service of process in any
such jurisdiction.

           (f) notwithstanding the foregoing, if at any time or from time to
time after the date of effectiveness of the registration statement, the Company
notifies the Holder in writing of the existence of a Potential Material Event,
the Holder shall not offer or sell any Registrable Securities, or engage in any
other transaction involving or relating to the Registrable Securities, from the
time of the giving of notice with respect to a Potential Material Event until
such Holder receives written notice from the Company that such Potential
Material Event either has been disclosed to the public or no longer constitutes
a Potential Material Event; provided, however, that the Company may not so
suspend the right to such Holder of Registrable Securities for more than twenty
(20) business day periods in the aggregate during any 12-month period with at
least a ten (10) business day interval between such periods, during the periods
the registration statement is required to be in effect ("Permitted Suspension
Period");

           "Potential Material Event" shall mean any of the following: (i) the
possession by the Company of material information not ripe for disclosure in a
registration statement, which shall

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be evidenced by determination in good faith by the Board of Directors of the
Company that disclosure of such information in the registration statement would
be detrimental to the business and affairs of the Company; or (ii) any material
engagement or activity by the Company which would, in the good faith
determination of the Board of Directors of the Company, be adversely affected by
disclosure in a registration statement at such time, which determination shall
be accompanied by a good faith determination by the Board of Directors of the
Company that the registration statement would be materially misleading absent
the inclusion of such information.

           2.04. Cooperation by Prospective Sellers, etc.

           (a) The Holder will furnish to the Company in writing such
information as the Company may reasonably require from the Holder or as required
by the Commission, and otherwise reasonably cooperate with the Company in
connection with any registration statement with respect to such Registrable
Securities.

           (b) The Holder of Registrable Securities included in any registration
statement will not (until further notice) effect sales thereof after receipt of
telegraphic or written notice from the Company to suspend sales to permit the
Company to correct or update such registration statement or prospectus.

           2.05. Registration Expenses.

           (a) The following costs and expenses incurred or sustained in
connection with or arising out of each registration pursuant to Section 2.02
shall constitute "Registration Expenses": all registration and filing fees, fees
and expenses of compliance with securities or Blue Sky laws, printing expenses,
messenger, telephone and delivery expenses, fees and disbursements of counsel
for the Company, fees and disbursements of all independent certified public
accountants (including the expenses relating to the preparation and delivery of
any special audit or "cold comfort" letters required by or incident to such
registration), and fees and disbursements of underwriters (excluding discounts
and commissions), the reasonable fees and expenses of any special experts
retained by the Company of its own initiative or at the request of the managing
underwriters in connection with such registration, and fees and expenses of all
(if any) other persons retained by the Company. The term "Registration Expenses"
shall not include, however, any legal fees or disbursements of counsel for the
Holder of Registrable Securities.

           (b) To the extent that Registration Expenses incident to any
registration are, under the terms of this Article II, not required to be paid by
the Company, each Holder of Registrable Securities included in such registration
will pay all Registration Expenses which are clearly solely attributable to the
registration of such Holder's Registrable Securities so included in such
registration, and all other Registration Expenses not so attributable to one
Holder will be borne and paid by all sellers of securities included in such
registration in proportion to the number of securities so included by each such
seller.

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           2.06. Indemnification.

           (a) Indemnification by the Company. The Company will indemnify the
Holder, the officers, directors and partners of each such Holder and each person
who controls any thereof (within the meaning of the Securities Act), against any
and all claims, losses, damages and liabilities (or actions in respect thereof)
arising out of or based on any untrue statement (or alleged untrue statement) of
any material fact contained in any prospectus, offering circular or other
document incident to any registration, qualification or compliance (or in any
related registration statement, notification or the like) or any omission (or
alleged omission) to state therein any material fact required to be stated
therein or necessary to make the statements therein not misleading, or any
violation by the Company of any rule or regulation promulgated under the
Securities Act applicable to the Company and relating to any action or inaction
required of the Company in connection with any such registration, qualification
or compliance, and the Company will reimburse each such Holder, officer,
director, partner and controlling person for any legal and any other expenses
reasonably incurred in connection with investigating or defending any such
claim, loss, damage, liability or action; provided, however, that the Company
will not be liable in any such case to the extent that any such claim, loss,
damage or liability arises out of or is based on any untrue statement or
omission based upon written information furnished to the Company in an
instrument duly executed by such Holder, officer, director, partner or
controlling person and stated to be exclusively and specifically for use
therein.

           (b) Indemnification by the Holder. The Holder will indemnify the
Company and its officers and directors and each person, if any, who controls any
thereof (within the meaning of the Securities Act) and, if required by the
underwriter effecting the related registration, such underwriter, and their
respective successors in title and assigns against any and all claims, losses,
damages and liabilities (or actions in respect thereof) arising out of or based
on any untrue statement (or alleged untrue statement) of any material fact
contained in any prospectus, offering circular or other document incident to any
registration, qualification or compliance (or in any related registration
statement, notification or the like) or any omission (or alleged omission) to
state therein any material fact required to be stated therein or necessary to
make the statement therein not misleading, and the Holder will reimburse the
Company and each other person indemnified pursuant to this paragraph (b) for any
legal and any other expenses reasonably incurred in connection with
investigating or defending any such claim, loss, damage, liability or action.

           (c) Indemnification Proceedings. Each party entitled to
indemnification pursuant to this Section 2.06 (the indemnified party) shall give
notice to the party required to provide indemnification pursuant to this Section
2.06 (the indemnifying party) promptly after such indemnified party acquires
actual knowledge of any claim as to which indemnity may be sought, and shall
permit the indemnifying party (at its expense) to assume the defense of any
claim or any litigation resulting therefrom; provided that counsel for the
indemnifying party, who shall conduct the defense of such claim or litigation,
shall be acceptable to the indemnified party, and the indemnified party may
participate in such defense at such party's expense; and provided, further, that
the failure by any indemnified party to give notice as provided in this
paragraph (c) shall not relieve the indemnifying party of its obligations under
this Section 2.06 except to the extent that the failure results in a failure of
actual notice to the indemnifying party and such

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indemnifying party is damaged solely as a result of the failure to give notice.
No indemnifying party, in the defense of any such claim or litigation, shall,
except with the consent of each indemnified party, consent to entry of any
judgment or enter into any settlement which does not include as an unconditional
term thereof the giving by the claimant or plaintiff to such indemnified party
of a release from all liability in respect to such claim or litigation. The
reimbursement required by this Section 2.06 shall be made by periodic payments
during the course of the investigation or defense, as and when bills are
received or expenses incurred.

           2.07. Rule 144 Requirements. The Company make publicly available and
available to the Holder of Registrable Securities, pursuant to Rule 144 of the
Commission under the Securities Act, such information as shall be necessary to
enable the Holders of Registrable Securities to make sales of Registrable
Securities pursuant to that Rule. The Company will furnish to any Holder of
Registrable Securities, upon request made by such Holder at any time, a written
statement signed by the Company, addressed to such Holder, describing briefly
the action the Company has taken or proposes to take to comply with the current
public information requirements of Rule 144. The Company will, at the request of
any Holder of Registrable Securities, upon receipt from such Holder of a
certificate certifying (i) that such Holder has held such Registrable Securities
for a period of not less than one (1) year, (ii) that such Holder has not been
an affiliate (as defined in Rule 144) of the Company for more than the ninety
(90) preceding days, and (iii) as to such other matters as may be appropriate in
accordance with such Rule, remove from the stock certificates representing such
Registrable Securities that portion of any restrictive legend which relates to
the registration provisions of the Securities Act, provided, however, in the
event that Foley, Hoag & Eliot LLP is no longer counsel to Company, counsel to
Holder may provide such instructions to the transfer agent regarding the removal
of the restrictive legend.

           2.08. Miscellaneous.

           (a) No Inconsistent Agreements. The Company will not, at any time
after the date of the Subscription Agreement, enter into any agreement or
contract (whether written or oral) with respect to any of its securities which
prevents the Company from complying in any respect with the registration rights
granted by the Company to the Holder of Registrable Securities pursuant to
Article II of this Agreement.

           (b) Amendments and Waivers. The provisions of Article II of this
Agreement, including the provisions of this paragraph (b), may not be amended,
modified or supplemented, and any waiver or consent to or any departure from any
of the provisions of Article II of this Agreement may not be given and shall not
become or be effective, unless and until (in each case) the Company shall have
received the prior written consent of the Holder of the Registrable Securities
for any such amendment, modification, supplement, waiver or consent.

           (c) Permitted Transferees.

                     (i) All of the agreements contained in, and all of the
rights granted by the Company pursuant to, Article II of this Agreement shall
inure to the benefit of and be binding upon the Purchaser.

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                     (ii) None of the agreements contained in, and none of the
rights granted by the Company pursuant to, Article II of this Agreement shall be
assignable or transferable (by operation of law or otherwise) by the Purchaser
to any person except pursuant to the terms of the Subscription Agreement.

           (e) Term. The agreements of the Company contained in Article II of
this Agreement shall continue in full force and effect so long as any Holder
holds any Registrable Securities.

           (f) Governing Law. The provisions of this Agreement shall be governed
by and construed in accordance with the laws (other than the choice-of-law
rules) of the State of Delaware.

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           IN WITNESS WHEREOF, the undersigned Purchaser and the Company have
caused this Agreement to be duly executed as of the date first above written.


                                          DYNAGEN, INC.


                                          By: _____________________________
                                          Name:____________________________
                                          Title:___________________________


                                          PURCHASER

                                          [Name]

                                          By: _____________________________
                                          Name:____________________________
                                          Title:___________________________



















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