AGREEMENT OF MERGER

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Exhibit 10.10

AGREEMENT OF MERGER

This Agreement of Merger (this "Agreement") is made and entered into as of

December 27, 2002 by and among Synta Pharmaceuticals Corp., a Delaware

corporation ("Synta"), DGN Genetics Acquisition Corp., a Delaware corporation

(the "Merger Sub", and together with Synta, the "Buyers"), Diagon Genetics,

Inc., a Delaware corporation ("Diagon"), and Dr. Safi R. Bahcall, Dr. Lan Bo

Chen and Lin-Huey Chen and Lynn T. Lee, Trustees for the Lan Bo Chen and

Lin-Huey Chen Irrevocable Trust dtd 12/19/95 (each a "Stockholder" and

collectively, the "Stockholders").

W I T N E S S E T H:

WHEREAS, the Stockholders collectively own all of the issued and

outstanding shares of the capital stock (the "Stock") of Diagon as set forth in

EXHIBIT A hereto;

WHEREAS, the respective boards of directors of Synta, the Merger Sub and

Diagon have approved the merger of Diagon with and into the Merger Sub (the

"Merger"), pursuant to and subject to the conditions set forth herein and in

accordance with the laws of the State of Delaware;

WHEREAS, subsequent to the Merger and prior to January 1, 2003, Synta

intends to merge the Merger Sub with and into Synta in accordance with the laws

of the State of Delaware; and

WHEREAS, Synta, the Merger Sub, Diagon and the Stockholders desire to make

certain representations, warranties and agreements in connection with the

Merger;

NOW, THEREFORE, in consideration of the mutual covenants and agreements set

forth in this Agreement and for other good and valuable consideration, the

receipt and sufficiency of which are hereby acknowledged, the parties hereto

agree as follows:

ARTICLE I

THE MERGER

Section 1.1 THE MERGER. At the Effective Time (as defined in

Section 1.2), Diagon shall be merged with and into the Merger Sub (Diagon

together with Merger Sub, the "Constituent Corporations") in accordance with the

applicable provisions of the Delaware General Corporation Law ("DGCL"), and the

separate existence of Diagon shall thereupon cease; and the Merger Sub, as the

surviving corporation in the Merger (the "Surviving Corporation"), shall

continue its corporate existence in accordance with the DGCL.

Section 1.2 EFFECTIVE TIME OF THE MERGER. At the Closing, the

Merger Sub shall cause the Merger to be consummated by filing with the Secretary

of State of Delaware an appropriate Certificate of Merger (the "Certificate of

Merger") duly executed in accordance with this Agreement and the DGCL. The date

and time at which the Certificate of Merger is filed is referred to herein as

the "Effective Time"

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Section 1.3 CERTIFICATE OF INCORPORATION. The Certificate of

Incorporation of the Merger Sub as in effect at the Effective Time shall be the

Certificate of Incorporation of the Surviving Corporation; PROVIDED, HOWEVER,

that Article 1 of the Certificate of Incorporation shall be amended to read as

follows: "The name of the corporation is Diagon Genetics, Inc."

Section 1.4 BY-LAWS. The by-laws of Merger Sub as in effect at the

Effective Time shall be the by-laws of the Surviving Corporation.

Section 1.5 DIRECTORS AND OFFICERS. The directors and officers of

the Surviving Corporation at the Effective Time shall be the directors and

officers of Merger Sub in office immediately prior to the Effective Time, each

to serve in accordance with the by-laws of the Surviving Corporation.

Section 1.6 RIGHTS AND LIABILITIES OF SURVIVING CORPORATION. At the

Effective Time, the Surviving Corporation shall succeed to all the properties

and assets of the Constituent Corporations and to all debts, choses in action

and other interests due or belonging to the Constituent Corporations and shall

be subject to and responsible for all the debts, liabilities and duties of the

Constituent Corporations in accordance with Section 259 of the DGCL.

Section 1.7 CONVERSION OF SHARES. At the Effective Time, by virtue

of the Merger and without any action on the part of the holder of any securities

of the Constituent Corporations:

(a) each share of Stock then outstanding, and all rights with respect

thereto, shall be converted into and represent the right to receive the Merger

Consideration as defined in Section 2.2;

(b) each share of Stock, if any, held in Diagon's treasury shall be

canceled and retired without payment of any consideration therefor; and

(c) each outstanding stock option, warrant or other right, if any, to

purchase shares of the capital stock of Diagon, whether or not then exercisable

or vested, shall be canceled and no cash or other consideration shall be paid or

delivered in exchange therefor.

ARTICLE II

CLOSING; MERGER CONSIDERATION

Section 2.1 CLOSING. The closing of the transactions contemplated

hereby (the "Closing") shall take place at the offices of Nixon Peabody LLP, 101

Federal Street, Boston, MA 02110-1832, or at such other place as may be agreed

to by Stockholders and Synta, at 10:00 AM (Boston time) on or before December

27, 2002, or on such other date as may be agreed upon in writing by Stockholders

and Synta if subsequent to December 27, 2002 (the "Closing Date").

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Section 2.2 MERGER CONSIDERATION. Each Stockholder shall receive

for his Stock the number of shares of Common Stock, $.0001 par value per share,

of Synta ("Synta Shares") and cash payment set forth opposite his name on

EXHIBIT A (the "Merger Consideration"). The cash payment shall be made to each

Stockholder either via wire transfer of immediately available funds to the

account of the Stockholder, if such information has previously been provided to

Synta, or via check made payable to the order of the Stockholder. The method of

payment shall be determined by Synta in its discretion.

ARTICLE III

REPRESENTATIONS AND WARRANTIES OF STOCKHOLDERS

Diagon and each of the Stockholders hereby jointly and severally represent

and warrant to the Buyers as follows:

Section 3.1 TITLE TO SHARES. Each Stockholder owns of record and

beneficially, free and clear of all encumbrances, and has good title to the

number of shares of Stock as set forth on EXHIBIT A attached hereto. No

Stockholder is a party to any agreement, trust or other arrangement that in any

way restricts such Stockholder's ability to perform its obligations under this

Agreement, including, without limitation, voting or transferring such

Stockholder's shares of Stock.

Section 3.2 NO CONFLICT. The execution, delivery and performance of this

Agreement by each Stockholder does not and will not (a) conflict with or violate

any law or governmental order applicable to such Stockholder or any of such

Stockholder's respective assets, properties or businesses or (b) conflict with,

result in any breach of, constitute a default (or event which with the giving of

notice or lapse of time, or both, would become a default) under, require any

consent under, or give to others any rights of termination, amendment,

acceleration, suspension, revocation or cancellation of, or result in the

creation of any encumbrance on any of the shares of Stock owned by such

Stockholder pursuant to, any note, bond, mortgage or indenture, contract,

agreement, lease, sublease, license, permit, franchise or other instrument or

arrangement to which such Stockholder is a party or by which any of the shares

of Stock owned by such Stockholder is bound or affected, which would adversely

affect the ability of such Stockholder to carry out its obligations under, and

to consummate the transactions contemplated by, this Agreement.

Section 3.3 GOVERNMENTAL CONSENTS AND APPROVALS. The execution, delivery

and performance of this Agreement by each Stockholder does not and will not

require any consent, approval, authorization or other order of, action by,

filing with or notification to, any governmental authority.

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Section 3.4 LITIGATION. No action, suit, investigation or proceeding by

or against any Stockholder is pending or, to the knowledge of any Stockholder,

threatened before any court, arbitrator or administrative agency, which could

reasonably be expected to affect the legality, validity or enforceability of

this Agreement or the consummation of the transactions contemplated by this

Agreement.

Section 3.5 SECURITIES ACT. The Synta Shares issued by Synta to each

Stockholder pursuant to this Agreement are being acquired by such Stockholder

for investment only and not with a view to any public distribution thereof, and

such Stockholder will not offer to sell or otherwise dispose of the Synta Shares

so acquired by such Stockholder in violation of any of the registration

requirements of the Securities Act of 1933, as amended, or any applicable state

blue sky laws.

Section 3.6 NO BROKER. No broker, finder or investment banker is

entitled to any brokerage, finders or other fee or commission in connection with

the transactions contemplated by this Agreement based upon arrangements made by

or on behalf of any Stockholder or Diagon.

Section 3.7 ORGANIZATION, GOOD STANDING AND AUTHORITY OF DIAGON.

Diagon is a corporation duly organized, validly existing and in corporate good

standing under the laws of the State of Delaware. The execution and delivery of

this Agreement, and the consummation of the transactions contemplated hereby

have been duly authorized by Board of Directors of Diagon and, as set forth in

Section 3.14 hereof, by the Stockholders and no other proceedings or actions on

the part of Diagon is necessary to authorize this Agreement and the transactions

contemplated hereby except as set forth in Section 3.14 hereof. This Agreement

constitutes a valid and binding obligation of Diagon, enforceable in accordance

with its terms.

Section 3.8 CAPITAL STOCK OF DIAGON. The authorized capital stock of

Diagon consists of forty million (40,000,000) shares of Common Stock, $.0001 par

value per share (the "Diagon Common Stock"). As of the date hereof, three

thousand (3,000) shares of Diagon Common Stock are issued and outstanding, all

of which are validly issued, fully paid and nonassessable. None of the issued

and outstanding shares of Diagon Common Stock were issued in violation of any

preemptive rights. There are no options, warrants, convertible securities or

other rights, agreements, arrangements or commitments of any character relating

to the Stock or obligating Diagon to issue, sell or assign the Stock, or any

other interest in, the Stock. There are no outstanding contractual obligations

of Diagon to repurchase, redeem or otherwise acquire any shares of the Stock or

to provide funds to, or make any investment (in the form of a loan, capital

contribution or otherwise) in, any other person.

Section 3.9 FINANCIAL STATEMENTS OF DIAGON. The unaudited balance

sheet of Diagon as of November 30, 2002 and the related statement of income for

the period then ended, complete and correct copies of which have been delivered

to Synta previously, fairly present the financial position of Diagon as at such

date and the results of operations of Diagon for the period then ended, in each

case in accordance with U.S. generally accepted accounting principles

consistently applied for the period covered (subject to the normal year-end

adjustments).

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Section 3.10 NO MATERIAL ADVERSE CHANGE. Since November 30, 2002,

there has been no material adverse change in the properties, business,

prospects, results of operations or financial condition of Diagon.

Section 3.11 NO DEFAULT; NO CONFLICT WITH OTHER INSTRUMENTS. Diagon is

not in default under or in violation of any provision of its charter or by-laws.

Diagon is not in default under or in violation of any material indenture,

mortgage, deed of trust, note, debenture, or any material agreement, lease, or

other instrument or contract to which it is a party or by which it or any of it

properties or assets is bound or any judgment, decree, order, statute, rule or

regulation to which it is subject or by which it or any of its properties or

assets is bound. The performance of this Agreement and the consummation of the

transactions contemplated hereby do not and will not constitute a default under

any material indenture, mortgage, deed of trust, note, debenture, agreement,

lease or other material instrument or material contract or any such judgment,

decree, order, statute, rule or regulation with respect to which Diagon is a

party or subject or result in the creation of any lien, charge or encumbrance on

any of the properties or assets of Diagon.

Section 3.12 SUBSIDIARIES. Diagon has no subsidiaries.

Section 3.13 LITIGATION. There is (a) no action, suit, investigation or

proceeding pending or, to any Stockholder's knowledge, threatened before any

court, arbitrator or administrative agency against or affecting Diagon, (b) no

action, suit, investigation or proceeding pending or, to any Stockholder's

knowledge, threatened before any court, arbitrator or administrative agency

against or affecting Diagon that could have the effect of delaying or hindering

the transactions contemplated in this Agreement and (c) to any Stockholder's

knowledge, no default with respect to any judgment, order, writ, injunction or

decree of any court or any administrative agency against or affecting Diagon

that could have the effect of delaying or hindering the transaction contemplated

in this Agreement.

Section 3.14 REQUIRED CONSENTS AND APPROVALS. The performance of this

Agreement will not require any consent, approval, order, authorization,

registration, qualification or designation from any governmental authority or

pursuant to any agreement or other instrument by which Diagon, or any of its

properties or assets, is bound except (a) for such consents, approvals, orders,

authorizations, registrations, qualifications or designations that have already

been obtained and are in full force and effect on the date hereof, and (b) where

the failure to obtain such consents, approvals, orders, authorizations,

registrations, qualifications or designations would not prevent or delay the

consummation of the transactions contemplated by this Agreement, or otherwise

prevent the Stockholders from performing their obligations under this Agreement.

Each of the Stockholders agrees that the execution and delivery of this

Agreement shall constitute his vote for ado