Protecting groups for biological labeling

Abstract

Alpha-haloketones are useful alkylating agents for coupling to sulfhydryl-containing biomolecules. However, they react spontaneously with water, alkali and organic bases and therefore cannot be stored for extended periods of time in aqueous solutions, particularly in the presence of proteins at physiological pH. The present invention provides novel solutions to these problems, however, as novel compounds and compositions comprising protected haloketones are disclosed herein. Methods of preparing and using protected haloketones which are useful in a variety of applications—e.g., in assays and conjugation reactions—are also disclosed herein.

1 . A composition comprising a protected alkylating reagent wherein deprotection of said reagent is catalyzed by an enzyme.  
     
     
         2 . The composition of  claim 1 , wherein said reagent includes a protecting group selected from the group consisting of a phosphate, an ester, a carbohydrate, a nucleic acid, and a lipid.  
     
     
         3 . The reagent of  claim 1 , wherein said enzyme is selected from the group consisting of glycosidases, nucleases, lipases, esterases, hydroxylases and phosphatases.  
     
     
         4 . The reagent of  claim 3 , wherein said enzyme is a phosphatase.  
     
     
         5 . The reagent of  claim 3 , wherein said enzyme is a glycosidase.  
     
     
         6 . The composition of  claim 1 , wherein said reagent is a 4-halobutadienyl ether or ester.  
     
     
         7 . The composition of  claim 1 , wherein said reagent is a 2-halovinyl ether or ester.  
     
     
         8 . The reagent of  claim 7 , wherein said 2-halovinyl ether or ester is a 2-halovinyl monophosphate.  
     
     
         9 . The reagent of  claim 7 , wherein said vinyl group is substituted with one or two alkyl or aryl groups.  
     
     
         10 . The reagent of  claim 9 , wherein said alkyl or aryl groups are substituted or unsubstituted.  
     
     
         11 . The composition of  claim 1 , wherein said protected alkylating reagent is an α-haloketone.  
     
     
         12 . The composition of  claim 1 , wherein said protected alkylating reagent is α-bromoacetylbenzoic acid (BABA) or α-chloroacetylbenzoic acid (CABA).  
     
     
         13 - 56 . (canceled)