SAR and X-ray. A new approach combining fragment-based screening and rational drug design: application to the discovery of nanomolar inhibitors of Src SH2.

Article Details

Citation

Lesuisse D, Lange G, Deprez P, Benard D, Schoot B, Delettre G, Marquette JP, Broto P, Jean-Baptiste V, Bichet P, Sarubbi E, Mandine E

SAR and X-ray. A new approach combining fragment-based screening and rational drug design: application to the discovery of nanomolar inhibitors of Src SH2.

J Med Chem. 2002 Jun 6;45(12):2379-87.

PubMed ID
12036348 [ View in PubMed
]
Abstract

(pp60)Src is a protein involved in signal transduction and is mainly expressed in neurones, platelets, and osteoclasts. Its precise biological role was recently discovered with the KO experiments by Soriano that gave rise to no other apparent phenotype than osteopetrosis, a disease resulting in excedent bone formation. The SH2 domain of the Src family specifically recognizes a sequence of tetrapeptide featuring a phosphotyrosine and a lipophilic aminoacid at the +1 and +3 positions. Recently we engaged in the search for SH2 ligands via modular peptidomimicry of this tetrapetide. This gave rise to several families of nanomolar inhibitors; the best one incorporated a caprolactam scaffold, a biphenyl moiety, and a phosphotyrosine. However, these inhibitors still incorporated the phosphate group that confers good binding affinity to the protein. Phosphates have undesirable features for drug candidates, namely, high rate of hydrolysis of the phosphate group by phosphatases and high charge content precluding cell penetration. Therefore, while searching for optimal non-peptide ligands for Src SH2, we looked for phosphate replacements. For this, we have designed an SAR by fragment crystallography approach. The start of this work resulted from two experimental observations. First, the fact that phenyl phosphate itself displayed detectable binding affinity for Src SH2 permitted us to perform a screening of small aromatic compounds as phenyl phosphate surrogates. Second, the obtention of large Src SH2 crystals displaying a channel large enough for soaking purposes allowed structure determination of over 40 of these small aromatic compounds bound in the phosphotyrosine binding pocket. This search and the way it gave rise to low nanomolar range Src SH2 inhibitors devoid of phosphate groups will be the subject of the present paper.

DrugBank Data that Cites this Article

Binding Properties
DrugTargetPropertyMeasurementpHTemperature (°C)
Paratoulene phosphateProto-oncogene tyrosine-protein kinase SrcIC 50 (nM)9000N/AN/ADetails
PhenylphosphateProto-oncogene tyrosine-protein kinase SrcIC 50 (nM)5000000N/AN/ADetails
PhenylphosphateProto-oncogene tyrosine-protein kinase SrcIC 50 (nM)300000N/AN/ADetails
RU78191Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)2530000N/AN/ADetails
RU78191Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)200000N/AN/ADetails
RU78262Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)80000N/AN/ADetails
RU78262Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)300000N/AN/ADetails
RU78299Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)39000N/AN/ADetails
RU78299Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)500000N/AN/ADetails
RU78300Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)900000N/AN/ADetails
RU78300Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)95000N/AN/ADetails
RU79256Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)3230000N/AN/ADetails
RU79256Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)192000N/AN/ADetails
RU84687Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)0.25N/AN/ADetails
RU85053Proto-oncogene tyrosine-protein kinase SrcIC 50 (nM)450N/AN/ADetails