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Exhibit 4.2    
    


 
 

UNIT CERTIFICATE    




	[NO. U-            	 	             UNITS]
	

 	
 	

CUSIP                         

SEE REVERSE FOR CERTAIN DEFINITIONS




SYNGENCE CORPORATION  


 Unit Certificate  


 INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE  


EACH UNIT CONSISTING OF ONE SHARE

OF COMMON STOCK, $0.00001 PAR VALUE

AND ONE REDEEMABLE CLASS A WARRANT 


THIS
CERTIFIES THAT 


is
the owner of 


or
registered assigns (the "Registered Holder") is the owner of the number of Units specified above, each of which consists of one share of common stock, $0.00001 par value, of Syngence Corporation
(the "Common Stock"), and one redeemable Class A Warrant to purchase one share of Common Stock (the "Warrant"). On or prior to the Separation Time (as defined herein), the securities evidenced
by this certificate may be combined, exchanged or transferred only as Units, and the Common Stock and Class A Warrants evidenced by this Certificate may not be split up, exchanged or traded
separately. The Units may separate into shares of Common Stock and Class A Warrants as of the close of business on
                        , 2007, thirty calendar days after
the effective date of the public offering of Units (the "Separation Time"). The shares of Common Stock and the Class A Warrants comprising the Units shall be separately tradeable commencing on
the first day after the Separation Time on which the Nasdaq Capital Market is open for trading. The Class A Warrants comprising part of the Units are issued under and pursuant to a certain
Warrant Agreement dated as of                         , 2007 (the "Warrant Agreement"), between Syngence Corporation and
 [                        ], as Warrant Agent (the "Warrant Agent"), and are
subject to the terms and
provisions contained therein and on the face of the certificates covered thereby, to all of which terms and provisions the holder of this Unit Certificate consents by acceptance hereof. The Warrant
Agreement provides for adjustment in the number of shares of Common Stock to be delivered upon the exercise of Class A Warrants evidenced hereby and to the exercise price of such Class A
Warrants in certain events therein set forth. Subject to the foregoing, the number of Class A Warrants and the number of shares of Common Stock comprising the Units are equal. 


Copies
of the Warrant Agreement are available for inspection at the stock transfer office of the Warrant Agent and Registrar or may be obtained upon written request addressed to Syngence Corporation,
5151 Belt Line Road, Suite 1100, Dallas, Texas 75254, Attention: Chief Financial Officer. 



This
Unit Certificate is not valid unless countersigned by the Warrant Agent and Registrar of the Company. 








IN
WITNESS WHEREOF, Syngence Corporation has caused this Unit Certificate to be duly executed manually or in facsimile by two of its officers thereunto duly authorized. 


Dated:




	 	 	 	Syngence Corporation
	

 	

 	
 	

By:	

 
	 	 	 	 	
[President and Chief Executive Officer]
	

 	

 	
 	

Attest:	

 
	 	 	 	 	
 Secretary
	

 Countersigned	
 	

 	

 
	
[Warrant Agent]	
 	

 	

 
	

By:	

 	
 	

 	

 
	 	
 Authorized Signature	 	 	 









 
 

SYNGENCE CORPORATION    



The
Registered Holder hereby is entitled, at any time after the Separation Time (as defined on the face hereof) to exchange the Units represented by this Unit Certificate for Common Stock
Certificate(s) representing one share of Common Stock for each Unit represented by this Unit Certificate and a Class A Warrant Certificate(s) representing one redeemable Class A Warrant
for each Unit represented by this Unit Certificate upon surrender of this Unit Certificate to the Warrant Agent and Registrar together with any documentation required by such agent. 


REFERENCE
IS MADE TO THE WARRANT AGREEMENT REFERRED TO ON THE FACE HEREOF, AND THE PROVISIONS OF SUCH WARRANT AGREEMENT SHALL FOR ALL PURPOSES HAVE THE SAME EFFECT AS THOUGH FULLY SET FORTH ON THE
FACE OF THIS CERTIFICATE. COPIES OF THE WARRANT AGREEMENT MAY BE OBTAINED UPON WRITTEN REQUEST FROM THE WARRANT AGENT AND REGISTRAR,
[                        ] 


The
following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations. 



	TEN COM—	as tenants in common	 	UNIF GIFT MIN ACT—	           	Custodian	                
	TEN ENT—	as tenants by the entireties	 	 	(Cust)	 	(Minor)
	JT TEN—	as joint tenants with rights of	 	under Uniform Gifts to Minors Act	                
	 	survivorship and not as tenants	 	 	 	 	(State)
	 	in common	 	UNIF TRF MIN ACT—	           	Custodian	                
	 	 	 	 	(Cust)	 	(Minor)
	 	 	 	under Uniform Transfers to Minors Act	                
	 	 	 	 	 	 	(State)





Additional abbreviations may also be used though not in the above list. 







FORM OF ASSIGNMENT 


(TO
BE SIGNED ONLY UPON ASSIGNMENT) 



	FOR VALUE RECEIVED,	 
	 	

	

hereby sell(s), assign(s), and transfer(s) unto
	

(PLEASE INSERT SOCIAL SECURITY

OR OTHER IDENTIFYING NUMBER

OF ASSIGNEE)
	

	

 
	

	

 





	

 (PLEASE PRINT NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)





	 	Shares
	
	 
	

	

 
	of the Units represented by the within Certificate, and do(es) hereby irrevocably constitute and appoint
	 	Attorney
	
	 
	to transfer the said Units on the books of the within named Corporation with full power of substitution in the premises.





        Dated: 



	
 (Signature must conform in all respects to the name of Registered Holder as specified on the face of this Warrant Certificate in every particular, without alteration or any change whatsoever, and
the signature must be guaranteed in the usual manner.)	 	 
	

Signatures Guaranteed: Medallion Guarantee Stamp	
 	

 
	

 The signature(s) should be guaranteed by an eligible guarantor institution (banks, stockbrokers, savings and loan association and credit unions) with membership in an approved signature
guarantee medallion program, pursuant to S.E.C. Rule 17Ad-15.	
 	

 













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Exhibit 4.2


UNIT CERTIFICATE

SYNGENCE CORPORATION