Linked Life Data

8691424

Source:http://linkedlifedata.com/resource/pubmed/id/8691424

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1996-8-23
pubmed:abstractText
A broad screening of phytochemicals has demonstrated that certain flavone and flavonol derivatives have a relatively high affinity at A3 adenosine receptors, with Ki values of > or = 1 microM (Ji et al. J. Med. Chem. 1996, 39, 781-788). We have further modified the flavone structure to achieve a degree of selectivity for cloned human brain A3 receptors, determined in competitive binding assays versus [125I]AB-MECA[N6-(4-amino-3-iodobenzyl)adenosine-5'-(N-methylur onamide)]. Affinity was determined in radioligand binding assays at rat brain A1 and A2a receptors using [3H]-N6-PIA ([3H]-(R)-N6-phenylisopropyladenosine) and [3H]CGS21680 [[3H]-2-[[4-(2-carboxyethyl)phenyl]ethylamino]-5'-(N-ethylcarbamoyl++ +)adenosine], respectively. The triethyl and tripropyl ether derivatives of the flavonol galangin, 4, had Ki values of 0.3 - 0.4 microM at human A3 receptors. The presence of a 5-hydroxyl group increased selectivity of flavonols for human A3 receptors. The 2',3,4',7-tetraethyl ether derivative of the flavonol morin, 7, displayed a Ki value of 4.8 microM at human A3 receptors and was inactive at rat A1/A2a receptors. 3,6-Dichloro-2'-(isopropyloxy)-4'-methylflavone, 11e, was both potent and highly selective (approximately 200-fold) for human A3 receptors (Ki = 0.56 microM). Among dihydroflavonol analogues, the 2-styryl instead of the 2-aryl substituent, in 15, afforded selectivity for human A3 vs rat A1 or A2A receptors. The 2-styryl-6-propoxy derivative, 20, of the furanochromone visnagin was 30-fold selective for human A3 receptors vs either rat A1 or A2A receptors. Several of the more potent derivatives effectively antagonized the effects of an agonist in a functional A3 receptor assay, i.e. inhibition of adenylyl cyclase in CHO cells expressing cloned rat A3 receptors. In conclusion, these series of flavonoids provide leads for the development of novel potent and subtype selective A3 antagonists.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2293-301
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:8691424-Animals, pubmed-meshheading:8691424-Brain Chemistry, pubmed-meshheading:8691424-CHO Cells, pubmed-meshheading:8691424-Cricetinae, pubmed-meshheading:8691424-Drug Design, pubmed-meshheading:8691424-Flavonoids, pubmed-meshheading:8691424-Humans, pubmed-meshheading:8691424-Kinetics, pubmed-meshheading:8691424-Molecular Structure, pubmed-meshheading:8691424-Nerve Tissue Proteins, pubmed-meshheading:8691424-Protein Binding, pubmed-meshheading:8691424-Purinergic P1 Receptor Antagonists, pubmed-meshheading:8691424-Radioligand Assay, pubmed-meshheading:8691424-Rats, pubmed-meshheading:8691424-Receptor, Adenosine A2A, pubmed-meshheading:8691424-Receptors, Purinergic P1, pubmed-meshheading:8691424-Recombinant Fusion Proteins, pubmed-meshheading:8691424-Structure-Activity Relationship
pubmed:year
1996
pubmed:articleTitle
Synthesis and biological activities of flavonoid derivatives as A3 adenosine receptor antagonists.
pubmed:affiliation
Laboratory of Bioorganic Chemistry, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't