Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-3-17
pubmed:abstractText
Nabumetone is a phototoxic nonsteroidal antiinflammatory drug used for the treatment of osteoarthritis. However, nabumetone is considered a prodrug with its metabolite 6-methoxy-2-naphthylacetic acid the active form. Photophysical and photochemical studies on this metabolite have been undertaken. It undergoes photodecarboxylation in aerated aqueous and organic solvents. In addition to the accepted photodegradation pathway for related molecules, a new mechanism that implies generation of the naphthalene radical cation from the excited singlet and addition of O2 prior to the decarboxylation process has been demonstrated. Evidence for the involvement of the excited singlet state in this mechanism have been obtained by steady-state and time-resolved fluorescence experiments. The fluorescence quenching by O2 and the shorter singlet lifetime in aerated solvents support this assignment. Laser flash photolysis also supports this mechanism by showing the noninvolvement of the triplet in the formation of the naphthalene radical cation. Finally, the well-known electron acceptor CCl4 acts as an efficient singlet quencher, enhancing the route leading to the radical cation, preventing intersystem crossing to the triplet and thus resulting in a dramatic increase in the yield of 6-methoxy-2-naphthaldehyde, the major oxidative decarboxylation product; this constitutes unambiguous proof in favor of the new mechanistic proposals.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0031-8655
pubmed:author
pubmed:issnType
Print
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
173-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
A photophysical and photochemical study of 6-methoxy-2-naphthylacetic acid, the major metabolite of the phototoxic nonsteroidal antiinflammatory drug nabumetone.
pubmed:affiliation
Departamento de Química, Universidad Politécnica de Valencia, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't