As filed with the Securities and Exchange Commission on April 5, 2007

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-8

REGISTRATION STATEMENT
under the
SECURITIES ACT OF 1933

SYNTA PHARMACEUTICALS CORP.

(Exact Name of Registrant as Specified in Its Charter)

SYNTA PHARMACEUTICALS CORP. 2001 STOCK PLAN

SYNTA PHARMACEUTICALS CORP. 2006 STOCK PLAN

NON-QUALIFIED STOCK OPTION AGREEMENT, DATED MAY 27, 2004

(Full Titles of the Plan)

Safi R. Bahcall, Ph.D.

President and Chief Executive Officer

Synta Pharmaceuticals Corp.

45 Hartwell Avenue

Lexington, Massachusetts 02421

(781) 274-8200

(Name, Address and Telephone Number, Including Area Code, of Agent For Service)

CALCULATION OF REGISTRATION FEE

(1)    The number of shares of common stock, par value $0.0001 per share (“Common Stock”), stated above consists of the aggregate number of shares which may be sold (i) upon the exercise of options which have been granted under the Synta Pharmaceuticals Corp. 2001 Stock Plan (the “2001 Stock Plan”), the Synta Pharmaceuticals Corp. 2006 Stock Plan (the “2006 Stock Plan,” and together with the 2001 Stock Plan, the “Plans”) and a Non-Qualified Stock Option Agreement, dated May 27, 2004, by and between the Registrant and one of its directors (the “Director Agreement”) and (ii) upon the exercise of options or issuances of stock awards which may hereafter be granted under the 2006 Stock Plan.  The maximum number of shares which may be sold upon the exercise of such options or issuance of stock awards granted under the Plans and the Director Agreement is subject to adjustment in accordance with certain anti-dilution and other provisions of the Plans and the Director Agreement, respectively.  Accordingly, pursuant to Rule 416 under the Securities Act of 1933, as amended (the “Securities Act”), this Registration Statement covers, in addition to the number of shares stated above, an indeterminate number of shares which may be subject to grant or otherwise issuable after the operation of any such anti-dilution and other provisions of the Plans and the Director Agreement.

(2)   This calculation is made solely for the purpose of determining the registration fee pursuant to the provisions of Rule 457(c) and (h) under the Securities Act as follows: (i) in the case of shares of Common Stock which may be purchased upon exercise of outstanding options, the fee is calculated on the basis of the price at which the options may be exercised; and (ii) in the case of shares of Common Stock for which options and stock awards have not yet been granted and the option price of which is therefore unknown, the fee is calculated on the basis of the average of the high and low sale prices per share of the Common Stock on The Nasdaq Global Market as of a date (April 3, 2007) within five business days prior to filing this Registration Statement.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1.    Plan Information.

The information required by Item 1 is included in documents sent or given to participants in the Synta Pharmaceuticals Corp. 2001 Stock Plan (the “2001 Stock Plan”), the Synta Pharmaceuticals Corp. 2006 Stock Plan (the “2006 Stock Plan,” and together with the 2001 Stock Plan, the “Plans”) and the Non-Qualified Stock Option Agreement, dated May 27, 2004, by and between the Registrant and one of its directors (the “Director Agreement”) pursuant to Rule 428(b)(1) of the Securities Act of 1933, as amended (the “Securities Act”).

Item 2.    Registrant Information and Employee Plan Annual Information.

The written statement required by Item 2 is included in documents sent or given to participants in the Plans and the Director Agreement pursuant to Rule 428(b)(1) of the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.    Incorporation of Certain Documents by Reference.

The following documents filed by the Registrant with the Commission are incorporated herein by reference:

(a)                                  The Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2006 (File No. 001-33277).

(b)                                 The Registrant’s Current Report on Form 8-K filed with the Commission on March 2, 2007 (File No. 001-33277).

(b)                                 The description of the Registrant’s Common Stock contained in the Registrant’s Registration Statement on Form 8-A (File No. 001-33277) filed with the Commission under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), on January 26, 2007, including any amendment or report filed for the purpose of updating such description.

All reports and other documents filed by the Registrant after the date hereof pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be part hereof from the date of filing of such reports and documents.  Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for the purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

Item 4.    Description of Securities.

Not applicable.

Item 5.    Interests of Named Experts and Counsel.

None.

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Item 6.    Indemnification of Directors and Officers.

Incorporated by reference from Part II, Item 14 “Indemnification of Directors and Officers” of the Registrant’s Registration Statement on Form S-1, as amended (File No. 333-138894).

Item 7.    Exemption from Registration Claimed.

Not applicable.

Item 8.    Exhibits.

The Index of Exhibits immediately following the signatures to this Registration Statement is incorporated herein by reference.

Item 9.    Undertakings.

(a)                                  The undersigned Registrant hereby undertakes:

(1)           To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i)            To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii)           To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement.  Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement.

(iii)          To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in this registration statement.

(2)           That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3)           To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(b)                                 The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by

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                                                reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c)                                  Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable.  In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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SIGNATURES

The Registrant.  Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Lexington, Massachusetts on April 5, 2007.

Each person whose signature appears below constitutes and appoints Safi R. Bahcall, Ph.D. and Keith S. Ehrlich, and each of them singly, his true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them singly, for him and in his name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement of Synta Pharmaceuticals Corp. and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting to the attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in or about the premises, as full to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that the attorneys-in-fact and agents or any of each of them or their substitute may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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INDEX OF EXHIBITS

*                 Filed herewith.

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Exhibit 5.1

April 5, 2007

Synta Pharmaceuticals Corp.

45 Hartwell  Avenue

Lexington, MA 02421

Ladies and Gentlemen:

We have acted as counsel to Synta Pharmaceuticals Corp., a Delaware corporation (the “Company”), in connection with the preparation and filing with the Securities and Exchange Commission (the “Commission”) of a Registration Statement on Form S-8 (the “Registration Statement”), pursuant to which the Company is registering the issuance under the Securities Act of 1933, as amended, of a total of 5,434,970 shares (the “Shares”) of its common stock, $0.0001 par value per share (the “Common Stock”).  This opinion is being rendered in connection with the filing of the Registration Statement with the Commission.  All capitalized terms used herein and not otherwise defined shall have the respective meanings given to them in the Registration Statement.

In connection with this opinion, we have examined the Company’s Restated Certificate of Incorporation and Restated By-Laws, both as currently in effect; such other records of the corporate proceedings of the Company and certificates of the Company’s officers as we have deemed relevant; and the Registration Statement and the exhibits thereto.

In our examination, we have assumed the genuineness of all signatures, the legal capacity of natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as certified or photostatic copies and the authenticity of the originals of such copies.

Based upon the foregoing, we are of the opinion that (i) the Shares have been duly and validly authorized by the Company and (ii) the Shares, when sold, will have been duly and validly issued, fully paid and non assessable shares of Common Stock, free of preemptive rights.

Our opinion is limited to applicable provisions of the Delaware Constitution, the General Corporation Laws of the State of Delaware and the reported judicial decisions interpreting those laws, and we express no opinion with respect to the laws of any other jurisdiction. No opinion is expressed herein with respect to the qualification of the Shares under the securities or blue sky laws of any state or any foreign jurisdiction.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

Boston | Washington | New York | Stamford |  Los Angeles | Palo Alto | San Diego | London

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

Synta Pharmaceuticals Corp.

April 5, 2007

Please note that we are opining only as to the matters expressly set forth herein, and no opinion should be inferred as to any other matters. This opinion is based upon currently existing statutes, rules, regulations and judicial decisions, and we disclaim any obligation to advise you of any change in any of these sources of law or subsequent legal or factual developments which might affect any matters or opinions set forth herein.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement.

EXHIBIT 23.2

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Board of Directors

Synta Pharmaceuticals Corp.

We consent to the incorporation by reference in the registration statement on Form S-8 of Synta Pharmaceuticals Corp. with respect to the consolidated balance sheets of Synta Pharmaceuticals Corp. as of December 31, 2006 and 2005, and the related consolidated statements of operations, stockholders’ equity (deficit) and comprehensive loss, and cash flows for each of the years in the three-year period ended December 31, 2006, and the period from inception (March 10, 2000) to December 31, 2006, which report appears in the December 31, 2006 annual report on Form 10-K of Synta Pharmaceuticals Corp.

Our report includes a paragraph that states that the Company adopted Statement of Financial Accounting Standard (SFAS) No.123R, Share-Based Payment, effective January 1, 2006.

/s/ KPMG LLP

Boston, Massachusetts

April 4, 2007