Linked Life Data

9397172

Source:http://linkedlifedata.com/resource/pubmed/id/9397172

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1998-1-12
pubmed:abstractText
The general class of 4-(phenylamino)quinazolines are potent (some members with IC50 values << 1 nM) and selective inhibitors of the tyrosine kinase activity of the epidermal growth factor receptor (EGFR), via competitive binding at the ATP site of the enzyme, but many of the early analogues had poor aqueous solubility (<< 1 mM). A series of 7-substituted 4-[(3-bromophenyl)-amino]pyrido[4,3-d]pyrimidines, together with selected (3-methylphenyl)amino analogues, were prepared by reaction of the analogous 7-fluoro derivatives with appropriate amine nucleophiles in 2-BuOH or aqueous 1-PrOH. All of the compounds were evaluated for their ability to inhibit the tyrosine-phosphorylating action of EGF-stimulated full-length EGFR enzyme. Selected analogues were also evaluated for their inhibition of autophosphorylation of the EGF receptor in A431 human epidermoid carcinoma cells in culture and against A431 tumor xenografts in mice. Analogues bearing a wide variety of polyol, cationic, and anionic solubilizing substituents retained activity, but the most effective in terms of both increased aqueous solubility (> 40 mM) and retention of overall inhibitory activity (IC50's of 0.5-10 nM against isolated enzyme and 8-40 nM for inhibition of EGFR autophosphorylation in A431 cells) were weakly basic amine derivatives. These results are broadly consistent with a proposed model for the binding of these compounds to EGFR, in which the 6- and 7-positions of the pyridopyrimidine ring are in a largely hydrophobic binding region of considerable steric freedom, at the entrance of the adenine binding cleft. The most active cationic analogues have a weakly basic side chain where the amine moiety is three or more carbon atoms away from the nucleus. Two of the compounds (bearing weakly basic morpholinopropyl and strongly basic (dimethylamino)butyl solubilizing groups) produced in vivo tumor growth delays of 13-21 days against advanced stage A431 epidermoid xenografts in nude mice, when administered i.p. twice per day on days 7-21 posttumor implant. Treated tumors did not increase in size during therapy and resumed growth at the termination of therapy, indicating an apparent cytostatic effect for these compounds under these treatment conditions. The data suggest that continuous long-term therapy with these compounds may result in substantial tumor growth inhibition.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3915-25
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Tyrosine kinase inhibitors. 13. Structure-activity relationships for soluble 7-substituted 4-[(3-bromophenyl)amino]pyrido[4,3-d]pyrimidines designed as inhibitors of the tyrosine kinase activity of the epidermal growth factor receptor.
pubmed:affiliation
Cancer Society Research Laboratory, Faculty of Medicine and Health Science, University of Auckland, New Zealand.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't