ABSTRACT
The activity of light-activatable ("caged") compounds can be temporally and spatially controlled, thereby providing a means to interrogate intracellular biochemical pathways as a function of time and space. Nearly all caged peptides contain photocleavable groups positioned on the side chains of key residues. We describe an alternative active site targeted strategy that disrupts the interaction between the protein target (SH2 domain, kinase, and proteinase) and a critical amide NH moiety of the peptide probe.
Subject(s)
Oligonucleotide Probes/chemistry , Binding Sites , Cyclic AMP-Dependent Protein Kinases/chemistry , Cyclic AMP-Dependent Protein Kinases/drug effects , Light , Models, Molecular , Molecular Structure , Oligonucleotide Probes/pharmacology , Oligonucleotide Probes/radiation effects , Peptide Hydrolases/chemistry , Peptide Hydrolases/drug effects , Phosphorylation , Photochemistry , Protein Binding , Sensitivity and Specificity , Structure-Activity Relationship , Time Factors , src Homology Domains/drug effectsABSTRACT
A potent and highly selective inhibitor of protein kinase C alpha has been generated via the combinatorial modification of a consensus sequence peptide. The inhibitor displays a Ki of 800 pM versus variable peptide substrate and good selectivity versus other members of the PKC family, including PKCbeta (385-fold), PKCgamma (580-fold), PKCdelta (2730-fold), PKCepsilon (600-fold), PKCeta (1310-fold), PKCtheta (1210-fold), PKCiota (940-fold), and PKCzeta (640-fold). The parallel synthesis strategy employed is easily automated and straightforward to implement.
Subject(s)
Enzyme Inhibitors/chemical synthesis , Peptides/chemical synthesis , Protein Kinase C/antagonists & inhibitors , Adenosine Triphosphate/chemistry , Adenosine Triphosphate/pharmacology , Binding, Competitive , Combinatorial Chemistry Techniques , Consensus Sequence , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Peptides/chemistry , Peptides/pharmacology , Protein Kinase C-alpha , Structure-Activity Relationship , Substrate SpecificityABSTRACT
The sequential low-temperature addition reaction of an organolithium compound and methyl triflate to (menthyloxy)(3-furyl)carbene complexes of chromium and tungsten proceeded with excellent regioselectivity (1,4-addition) and diastereoselectivity (2,3-trans disposition of the nucleophile and electrophile groups) to afford new 2,3-disubstituted (2,3-dihydro-3-furyl)carbene complexes. In addition, a high degree of diastereofacial selectivity was achieved by employing alkenyllithium compounds. After detachment of both the metal fragment and the chiral auxiliary group, trisubstituted 2,3-dihydrofuran derivatives containing a quaternary stereogenic center at the C3 position were obtained. The characterization, including X-ray crystallography, of a novel type of stable four-membered chelate (eta(2)-alkene)tetracarbonylcarbene complex of chromium is also reported.
