Linked Life Data

1479588

Source:http://linkedlifedata.com/resource/pubmed/id/1479588

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
1993-2-8
pubmed:abstractText
Certain phosphonocarboxylate analogues of phosphate are known to inhibit Na(+)-phosphate (Pi) cotransport in renal brush border membrane (BBM), but previously tested potential inhibitors incorporating structurally versatile aryl functionality were inactive. In this work, a series of novel alpha-halogenated [(phenylphosphinyl)methyl]phosphonates [PhpXYMP: X, Y = H, F (2); F, F (3); H, Cl (6); Cl, Cl (4); H, Br (7); Br, Br (5); and Cl, Br (8)] were prepared via synthesis of the corresponding triethyl esters, acid hydrolysis, and isolation as pyridine salts. The compounds were evaluated as inhibitors of Na(+)-gradient-dependent 32Pi uptake by rat renal cortex BBM vesicles (BBMV) in vitro. The PhpFMP racemate 2 had higher activity (-49% delta inhibition) than other members of the series (-22 to -39% delta inhibition). pKa values of 1.5-2.0, 2.7, and 7.1 were estimated for 2 using a 31P delta vs pH plot, indicating that in the activity assays it exists as both dianion and trianion, with the latter form predominant. PhpFMP had no significant inhibitory effect on Na(+)-gradient-dependent uptake of D-glucose or L-proline in the same BBMV, and did not inhibit BBM alkaline phosphatase. Kinetic analysis showed that PhpFMP acts as a strictly competitive inhibitor of Na(+)-Pi cotransport with Ki = 0.358 +/- 0.021 mM (n = 3). The racemate 2 was resolved as its (-)-quinine salt into enantiopure (+)-2 [Na+ salt, [alpha]25D = +6 degrees (aqueous MeOH)] and a Na+ salt of 2 enriched in (-)-2. The two compounds did not differ significantly as inhibitors of Na(+)-gradient dependent 32Pi uptake by rat renal cortex BBM vesicles (BBMV) in vitro. The results are discussed in terms of structural requirements for inhibition.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4885-92
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Alpha-halo [(phenylphosphinyl)methyl]phosphonates as specific inhibitors of Na(+)-gradient-dependent Na(+)-phosphate cotransport across renal brush border membrane.
pubmed:affiliation
Department of Chemistry, University of Southern California, Los Angeles 90089-0744.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't