MASTER LEASE AGREEMENT (QUASI) DATED AS OF NOVEMBER 10, 2004 ("AGREEMENT")

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Exhibit 10.19

MASTER LEASE AGREEMENT

(QUASI)

DATED AS OF NOVEMBER 10, 2004 ("AGREEMENT")

THIS AGREEMENT is between General Electric Capital Corporation (together with

its successors and assigns, if any, "Lessor") and Synta Pharmaceuticals Corp.

("Lessee"). Lessor has an office at 83 WOOSTER HEIGHTS ROAD, DANBURY, CT 06810.

Lessee is a corporation organized and existing under the laws of state of

Delaware. Lessee's mailing address and chief place of business is 45 HARTWELL

AVENUE, LEXINGTON, MA 02421. This Agreement contains the general terms that

apply to the leasing of Equipment from Lessor to Lessee. Additional terms that

apply the Equipment (term, rent, options, etc.) shall be contained on a schedule

("Schedule").

1. LEASING:

(a) Lessor agrees to lease to Lessee, and Lessee agrees to lease from Lessor,

the equipment and other property ("EQUIPMENT") described in any Schedule signed

by both parties.

(b) Lessor shall purchase Equipment from the manufacturer or supplier

("SUPPLIER") and lease it to Lessee if on or before the Last Delivery Date

(specified in the Schedule) Lessor receives (i) a Schedule for the Equipment,

(ii) evidence of insurance which complies with the requirements of Section 8,

and (iii) such other documents as Lessor may reasonably request. Each of the

documents required above must be in form and substance satisfactory to Lessor.

Lessor hereby appoints Lessee its agent for inspection and acceptance of the

Equipment from the Supplier. Once the Schedule is signed, the Lessee may not

cancel the Schedule.

2. TERM, RENT AND PAYMENT:

(a) The rent payable for the Equipment and Lessee's right to use the Equipment

shall begin on the earlier of (i) the date when the Lessee signs the Schedule

and accepts the Equipment or (ii) when Lessee has accepted the Equipment under a

Certificate of Acceptance ("LEASE COMMENCEMENT DATE"). The term of this

Agreement shall be the period specified in the applicable Schedule. The word

"term" shall include all basic and any renewal terms.

(b) Lessee shall pay rent to Lessor at its address stated above, except as

otherwise directed by Lessor. Rent payments shall be in the amount set forth in,

and due as stated in the applicable Schedule. If any Advance Rent (as stated in

the Schedule) is payable, it shall be due when the Lessee signs the Schedule.

Advance Rent shall be applied to the first rent payment. In no event shall any

Advance Rent or any other rent payments be refunded to Lessee. If rent is not

paid within ten (10) days of its due date, Lessee agrees to pay a late charge of

five cents ($.05) per dollar on, and in addition to, the amount of such rent but

not exceeding the lawful maximum, if any.

3. TAXES:

(a) If permitted by law, Lessee shall report and pay promptly all taxes, fees

and assessments due, imposed, assessed or levied against Lessor or Lessee on

account of any Equipment (or purchase, ownership, delivery, leasing, possession,

use or operation thereof) by any

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governmental entity or taxing authority during or related to the term of this

Agreement, including, without limitation, all license and registration fees, and

all sales, use, personal property, excise, franchise, stamp or other taxes,

imposts, duties and charges, together with any penalties, fines or interest

thereon(collectively "TAXES"). Lessee shall have no liability for Taxes imposed

by the United States of America or any State or political subdivision thereof or

any foreign jurisdiction which are on or measured by the net income of Lessor,

and any such Taxes are excluded from "Taxes" as such term is used throughout

this Agreement. Lessee shall promptly reimburse Lessor (on an after tax basis)

for any Taxes charged to or assessed against Lessor. Lessee shall send Lessor a

copy of each report or return and evidence of Lessees payment of Taxes upon

request.

(b) Lessee's obligations, and Lessor's rights and privileges, contained in this

Section 3 shall survive the expiration or other termination of this Agreement.

4. REPORTS:

(a) If any tax or other lien shall attach to any Equipment, Lessee will notify

Lessor in writing, within ten (10) days after Lessee becomes aware of the tax or

lien. The notice shall include the full particulars of the tax or lien and the

location of such Equipment on the date of the notice.

(b) Lessee will deliver to Lessor financial statements as follows: If Lessee is

a privately held company, then Lessee agrees to provide quarterly financial

statements, certified by Lessee's president or chief financial officer including

a balance sheet, statement of operations and cash flow statement within 30 days

of each quarter end and its complete audited annual financial statements,

certified by a reorganized firm of certified public accountants, within 120 days

of fiscal year end or at such time as Lessee's Board of Directors receives the

audit. If Lessee is a publicly held company, then Lessee agrees to provide

quarterly unaudited statements and annual audited statements, certified by a

recognized firm of certified public accountants, within 10 days after the

statements are provided to the Securities and Exchange Commission ("SEC") or

make such statements available on its website. All such statements are to be

prepared using generally accepted accounting principles ("GAAP") and, if Lessee

is a publicly held company, are to be in compliance with SEC requirements.

(c) Lessor may inspect any Equipment during normal business hours after giving

Lessee reasonable prior notice.

(d) Lessee will keep the Equipment at the Equipment Location (specified in the

applicable Schedule) and will give Lessor prior written notice of any relocation

of Equipment. If Lessor requests, Lessee will promptly notify Lessor in writing

of the location of any Equipment.

(e) If any Equipment is lost or damaged (where the estimated repair costs would

exceed the greater of ten percent (10%) of the original Equipment cost or ten

thousand and 00/100 dollars ($10,000), or is otherwise involved in an accident

causing personal injury or property damage, Lessee will promptly and fully

report the event to Lessor in writing.

(f) If Lessor requests, Lessee will furnish a certificate of an authorized

officer of Lessee stating that he has reviewed the activities of Lessees and

that, to the best of his knowledge, there

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exists no default or event which with notice or lapse of time (or both) would

become such a default within thirty (30) days after any request by Lessor.

(g) Lessee will promptly notify Lessor of any change in Lessee's state of

incorporation or organization.

5. DELIVERY, USE AND OPERATION:

(a) All Equipment shall be shipped directly from the Supplier to Lessee.

(b) Lessee agrees that the Equipment will be used by Lessee solely in the

conduct of its business and in a manner complying with all applicable laws,

regulations and insurance policies.

(c) Lessee will not move any equipment from its leased or owned locations

("LOCATION"), except for purposes of repair, refurbishment or maintenance, and

Lessee will not move any piece of Equipment with an original equipment value of

$25,000 or more from one Location to another Location without written

notification to Lessor.

(d) Lessee will keep the Equipment free and clear of all liens and encumbrances

other than those which result from acts of Lessor.

(e) Lessor shall not disturb Lessees quiet enjoyment of the Equipment during

the term of the Agreement unless a default has occurred and is continuing under

this Agreement.

6. MAINTENANCE:

(a) Lessee will, at its sole expense, maintain each unit of Equipment in good

operating order and repair, normal wear and tear excepted. The Lessee shall also

maintain the Equipment in accordance with manufacturers recommendations. Lessee

shall make all alterations or modifications required to comply with any

applicable law, rule or regulation during the term of this Agreement. If Lessor

requests, Lessee shall affix plates, tags or other identifying labels showing

ownership thereof by Lessee and Lessor's security interest therein. The tags or

labels shall be placed in a prominent position on each unit of Equipment.

(b) Lessee will not attach or install anything on the Equipment that will

impair the originally intended function or use of such Equipment without the

prior written consent of Lessor, which consent may not be withheld, conditioned

or delayed unreasonably. All additions, parts, supplies, accessories, and

equipment ("ADDITIONS") furnished or attached to any Equipment that are not

readily removable shall become subject to the lien or Lessor. All Additions

shall be made only in compliance with applicable law. Lessee will not attach or

install any Equipment to or in any other personal or real property without the

prior written consent of Lessor, which consent may not be withheld, conditioned

or delayed unreasonably.

7. STIPULATED LOSS VALUE: If for any reason any unit of Equipment becomes

lost, stolen, destroyed, irreparably damages or unusable ("CASUALTY

OCCURRENCES") Lessee shall promptly and fully notify Lessor in writing. Lessee

shall pay Lessor the sum of (i) the Stipulated Loss Value (see Schedule) of the

affected unit determined as of the rent payment date prior to the casualty

Occurrence; and (ii) all rent and other amounts which are then due under this

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Agreement on the Payment Date (defined below) for the affected unit. The Payment

Date shall be the next rent payment after the Casualty Occurrence. Upon payment

of all sums due hereunder, the term of this lease as to such unit shall

terminate.

8. INSURANCE:

(a) Lessee shall bear the entire risk of any loss, theft, damage to, or

destruction of, any unit of Equipment from any cause whatsoever from the time

the Equipment is delivered to Lessee and installed (if applicable).

(b) Lessee agrees, at its own expense, to keep all Equipment insured for such

amounts and against such hazards as Lessor may reasonably require. All such

policies shall be with companies, and on terms, reasonably satisfactory to

Lessor. The insurance shall include coverage for damage to or loss of Equipment,

liability for personal injuries, death or property damage. Lessor shall be named

as additional insured with a loss payable clause in favor of Lessor, as its

interest may appear, irrespective of any breach of warranty or other act or

omission of Lessee. The insurance shall provide for liability coverage in any

amount equal to at least ONE MILLION U.S. DOLLARS ($1,000,000.00) total

liability per occurrence, unless otherwise stated in any Schedule. The

casualty/property damage coverage shall be in an amount equal to the higher of

the Stipulated Loss Value or the full replacement cost of the Equipment. No

insurance shall be subject to any co-insurance clause. The insurance policies

shall provide that the insurance may not be altered or canceled by the insurer

until after thirty (30) days written notice to Lessor. Lessee agrees to deliver

to Lessor evidence of insurance reasonable satisfactory to Lessor.

(c) Lessee hereby appoints to Lessor as Lessee's attorney-in-fact to make proof

of loss and claim for insurance, and to make adjustments with insurers and to

receive payment of an execute or endorse all documents, checks or drafts in

connection with insurance payments. Lessor shall not act a Lessees

attorney-in-fact unless Lessee is in default. Lessee shall pay any reasonable

expenses if Lessor in adjusting or collecting insurance. Lessee will not make

adjustments with insurers except with respect to claims for damage to any unit

of Equipment where the repair costs are less than the lesser of ten percent

(10%) of the original Equipment cost or ten thousand and 00/100 dollars

($10,000). Lessor may, at its option, apply proceeds of insurance, in whole or

in part, to (i) repair or replace Equipment or any portion thereof, or (ii)

satisfy any obligation of Lessee to Lessor under this Agreement.

9. RETURN OF EQUIPMENT:

(a) At the expiration or termination of this Agreement or any Schedule, Lessee

shall perform any testing and repairs required to place the units of Equipment

in the same condition and appearance as when received by Lessee (reasonable wear

and tear excepted) and in good working order for the original intended purpose

of the Equipment. If required the units of Equipment shall be deinstalled,

disassembled and crated by an authorized manufacturer's representative or such

other service person as is reasonably satisfactory to Lessor. Lessee shall

remove installed markings that are not necessary for the operation, maintenance

or repair of the Equipment. All Equipment will be cleaned, cosmetically

acceptable, and in such condition as to be immediately installed into use in a

similar environment for which the Equipment was

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originally intended to be used. All waste material and fluid must be removed

from the Equipment and disposed of in accordance with then current waste

disposal laws. Lessee shall return the units of Equipment to a location within

the continental United States as Lessor shall direct. Lessee shall obtain and

pay for a policy of transit insurance for the redelivery period in an amount

equal to the replacement value of the Equipment. The transit insurance must name

Lessor as the loss payee. The Lessee shall pay for all costs to comply with this

section (a).

(b) Until Lessee has fully complied with the requirements of Section 9(a)

above, Lessee's rent payment obligation and all other obligations under this

Agreement shall continue from month to month notwithstanding any expiration or

termination of the lease term. Lessor may not terminate the Lessee's right to

use Equipment, unless Lessee is in default.

(c) Lessee shall provide to Lessor a detailed inventory of all components of

the Equipment including model and serial numbers. Lessee shall also provide an

up-to-date copy of all other documentation pertaining to the Equipment. All

service manuals, blueprints, process flow diagrams, operating manuals, inventory

and maintenance records shall be given to Lessor at least ninety (90) days and

not more than one hundred twenty (120) days prior to lease termination.

(d) Lessee shall make the Equipment available for on-site operational

inspections by potential purchasers at least one hundred twenty (120) days prior

to and continuing up to lease termination. Lessor shall provide Lessee with

reasonable notice prior to any inspection. Lessee shall provide personnel, power

and other requirements necessary to demonstrate electrical, hydraulic and

mechanical systems for each item of Equipment.

10. DEFAULT AND REMEDIES:

(a) Lessor may in writing declare this Agreement in default if: (i) Lessee

breaches its obligation to pay rent or any other sum when due and fails to cure

the breach within ten (10) days; (ii) Lessee breaches any of its insurance

obligations under Section 9; (iii) Lessee breaches any of its other obligations

and fails to cure that breach within thirty (30) days after written notice from

Lessor; (iv) any representation or warranty made by Lessee in connection with

this Agreement shall be false or misleading in any material respect; (v) Lessee

or any guarantor or other obligor for the Lessee's obligations hereunder

("GUARANTOR") becomes insolvent or ceases to do business as a going concern;

(vi) any Equipment is illegally used; (vii) if Lessee or any Guarantor is a

natural person, any death or incompetency of Lessee or such Guarantor; (viii) a

petition is filed by or against Lessee or any Guarantor under any bankruptcy or

insolvency laws and in the event of an involuntary petition, the petition is not

dismissed, within forty-five (45) days of the filing date; (ix) Lessee default

under any other material obligation for (A) borrowed money, (B) the deferred

purchase price of property, or (C) payments due under the lease agreement; (x)

there is any dissolution, termination or existence, merger, consolidation or

change in controlling ownership or Lessee or any Guarantor, but not to include

an initial public offering, or any other stock offering, preferred to common, in

which the primary purpose is to raise cash equity; or (xi) there is a material

adverse change in the Lessee's financial condition. The default declaration

shall apply to all Schedules unless specifically excepted by Lessor.

(b) After a default, at the request of Lessor, Lessee shall comply with the

provisions of Section 9(a) and the following provisions shall apply also. Lessee

hereby authorizes Lessor to

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peacefully enter any premises where any Equipment may be and take possession of

the Equipment. Lessee shall immediately pay to Lessor without further demand as

liquidated damages for loss of a bargain and not as a penalty, the Stipulated

Loss Value of the Equipment (calculated as of the rent payment date prior to the

declaration of default), and all rents and other sums then due under this

Agreement and all Schedules. Lessor may terminate this Agreement as to any or

all of the Equipment. A termination shall occur only upon written notice by

Lessor to Lessee and only as to the units of Equipment specified in any such

notice. Lessor may, but shall not be required to, sell Equipment at private or

public sale, in bulk or in parcels, with or without notice, and without having

the Equipment present at the place of sale. Lessor may also, but shall not be

required to, lease, otherwise dispose of or keep idle all or part of the

Equipment. Lessor may use Lessee's premises for a reasonable period of time for

any or all of the purposes stated above without liability for rent, costs,

damages or otherwise. The proceeds of sale, lease or other disposition, if any,

shall be applied in the following order of priorities: (i) to pay all of

Lessor's costs, charges and expenses incurred in taking, removing, holding,

repairing and selling, leasing or otherwise disposing of Equipment; then (ii) to

the extent not previously paid by Lessee, to pay Lessor all sums due from Lessee

under this Agreement; then (iii) to reimburse to Lessee any sums previously paid

by Lessee as liquidated damages; and then (iv) to Lessee, if there exists any

surplus. Lessee shall immediately pay any deficiency in (i) and (ii) above.

(c) The foregoing remedies are cumulative, and any or all thereof may be

exercised instead of or in addition to each other or any remedies at law, in

equity, or under statute. Lessee waives notice of sale or other disposition (and

the time and place thereof), and the manner and place of any advertising. Lessee

shall pay Lessor's actual attorney's fees incurred in connection with the

enforcement, assertion, defense or preservation of Lessor's rights and remedies

under this Agreement, or if prohibited by law, such lesser sum as may be

permitted. Waiver of any default shall not be a waiver of any other or

subsequent default.

(d) Any default under the terms of this or any other agreement between Lessor

and Lessee may be declared by Lessor a default under this and any such other

agreement.

11. ASSIGNMENT: LESSEE SHALL NOT SELL, TRANSFER, ASSIGN, ENCUMBER OR SUBLET ANY

EQUIPMENT OR THE INTEREST OF LESSEE IN THE EQUIPMENT WITHOUT THE PRIOR WRITTEN

CONSENT OF LESSOR. Lessor may, without the consent of Lessee, assign this

Agreement, any Schedule or the right to enter into a Schedule. Lessee agrees

that is Lessee receives written notice of an assignment from Lessor, Lessee will

pay all rent and all other amounts payable under any assigned Schedule to such

assignee or as instructed by Lessor. Lessee also agrees to confirm in writing

receipt of the notice of assignment as may be reasonably requested by assignee.

Lessee hereby waives and agrees not to assert against any such assignee any

defense, set-off, recoupment claim or counterclaim which Lessee has or may at

any time have against Lessor for any reason whatsoever.

12. NET LEASE: Lessee is unconditionally obligated to pay all rent and other

amounts due for the entire lease term no matter what happens, even if the

Equipment is damaged or destroyed, if it is defective or if Lessee no longer can

use it. Lessee is not entitled to reduce or set-off against rent or other

amounts due to Lessor or to anyone to whom Lessor assigns this Agreement or any

Schedule whether Lessees claim arises out of this Agreement, any Schedule, any

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statement by Lessor, Lessor's liability of any manufacturers liability, strict

liability, negligence or otherwise.

13. INDEMNIFICATION:

(a) Lessee hereby agrees to indemnify Lessor, its agents, employees, successors

and assigns (on an after tax basis) from and against any and all losses,

damages, penalties, injuries, claims, actions and suits, including legal

expenses, of whatsoever kind and nature arising out of or relating to the

Equipment or this Agreement, except to the extent the losses, damages,

penalties, injuries, claims, actions, suits or expenses result from Lessor's

gross negligence or willful misconduct ("CLAIMS"). This indemnity shall include,

but is not limited to, Lessor's strict liability in tort and Claims, arising out

of (i) the selection, manufacture, purchase,