Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-1-23
pubmed:abstractText
The mechanisms that trigger the phototoxic response to 2-chlorophenothiazine derivatives are still unknown. To better understand the relationship between the molecular structure of halogenated phenothiazines and their phototoxic activity, their photophysics and photochemistry were studied in several alcohols. The photodestruction quantum yields were determined under anaerobic conditions using monochromatic light (313 nm). Absorption- and emission-spectroscopy, (1)H- and (13)C-NMR and GC-MS were used to characterize the photoproducts and reference compounds. An electron transfer mechanism had been previously proposed by Bunce et al. (J. Med. Chem. 22, 202-204) to explain the large difference between the photodestruction quantum yield of 2-chlorpromazine (phi = 0.46) and 2-chlorphenothiazine (phi = 0.20). According to these authors, the alkylamino chain transfers an electron to the phenothiazine moiety. Our results demonstrate that this mechanism is incorrect, because the photodestruction quantum yields of all chlorinated derivatives of this study are the same under the same conditions of solvent and irradiation wavelength. The quantum yield has no dependence on the 10-substituent, but it depends on the solvent. The percentage of each photoproduct, on the other hand, strongly depends on that substituent, but not very much on the solvent. Finally, it is demonstrated that the phototoxic effect of chlorinated phenothiazines is not related to the photodechlorination, although both processes share the same transient.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-11456671, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-11837323, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-14209473, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-16833671, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-3018805, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-3018808, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-3241834, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-3306725, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-366639, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-423200, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-4399487, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-5425066, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-5676687, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-6103931, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-6454898, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-6844420, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-7462668, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-858946, http://linkedlifedata.com/resource/pubmed/commentcorrection/18673321-9825699
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0031-8655
pubmed:author
pubmed:issnType
Print
pubmed:volume
85
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
160-70
pubmed:dateRevised
2010-9-21
pubmed:meshHeading
pubmed:articleTitle
Photodegradation of 2-chloro substituted phenothiazines in alcohols.
pubmed:affiliation
Department of Chemistry, Humacao Campus, University of Puerto Rico, Humacao, Puerto Rico. carmelo.garcia@upr.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural