Design of substrate-site-directed irreversible inhibitors of adenosine 5'-phosphate aminohydrolase. Effect of substrate substituents on affinity for the substrate site.
Derivatives of adenosine 5'-phosphate (AMP) have been synthesized in which the phosphoester (POCH2) grouping of AMP is replaced by PCH(R)CH2 where R is OC(O)Me, CH2NHCOMe, CH2NHCOEt, and CH2NHCOOR' (R' = Me, Et, and Pr). The 2',3'-O-isopropylidene and 2', 3'-di-O-acetyl derivatives of AMP were also prepared. All compounds were competitive inhibitors of rabbit muscle AMP aminohydrolase with enzyme-inhibitor dissociation constants (Ki values) of 330, 20, 17, 19, 16, 14, 260, and 105 muM, respectively. All compounds were substrates except those in which R was CH2NHCOEt and CH2NHCOOR' (R'=Me, Et, and Pr). The previously described allo and talo epimers of 5'-C-acetylaminomethyl-AMP and the allo epimer of 5'-C-propionylaminomethyl-AMP were substrates and competitive inhibitors with Ki values of 18, 47, and 42 muM, respectively. The talo epimer of 5'-C-propionylaminomethyl-AMP was not a substrate and was a noncompetitive inhibitor, Ki
D000659:AMP Deaminase / Q000037:antagonists & inhibitors*; D000249:Adenosine Monophosphate / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D000818:Animals; D001665:Binding Sites; D002854:Chromatography, Paper; D004590:Electrophoresis, Paper; D066298:In Vitro Techniques; D007700:Kinetics; D009709:Nucleotide Deaminases / Q000037:antagonists & inhibitors*; D011817:Rabbits; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship
D000249:Adenosine Monophosphate; D009709:Nucleotide Deaminases; D000659:AMP Deaminase