Linked Life Data

10354403

Source:http://linkedlifedata.com/resource/pubmed/id/10354403

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1999-6-24
pubmed:abstractText
Several A-ring-modified analogues of the DNA-binding antitumor agent DC-81 (5) have been synthesized in order to study structure-reactivity/cytotoxicity relationships. For two molecules (23 and 30) the modifications required the addition of a fourth ring to give the novel dioxolo[4,5-h]- and dioxano[5,6-h]pyrrolo[2,1-c][1, 4]benzodiazepin-11-one (PBD) ring systems, respectively. Another three analogues (34, 38, and 48) have the native benzenoid A-ring replaced with pyridine, diazine, or pyrimidine rings to give the novel pyrrolo[2,1-c][1,4]pyridodiazepine, pyrrolo[2,1-c][1, 4]diazinodiazepine, and pyrrolo[2,1-c][1,4]pyrimidinodiazepine systems, respectively. The other new analogues (16a,b) have extended chains at the C8-position of the DC-81 structure. During the synthesis of these compounds, a novel tin-mediated regiospecific cleavage reaction of the dioxole intermediate 18 was discovered, leading to the previously unknown iso-DC-81 (20). In addition, an unusual simultaneous nitration-oxidation reaction of 4-(3-hydroxypropoxy)-3-methoxybenzoic acid (8) was found to produce 3-(4-carboxy-2-methoxy-5-nitrophenoxy)propanoic acid (9), a key intermediate, in high yield. In general, the results of cytotoxicity and DNA-binding studies indicated that none of the changes made to the A-ring of the PBD system significantly improved either binding affinity or cytotoxicity in comparison to DC-81. This result suggests that the superior potency of natural products such as anthramycin (1), tomaymycin (2), and sibiromycin (3) is due entirely to differences in C-ring structure, and in particular exo or endo unsaturation at the C2-position and C2-substituents containing unsaturation. This study also provided information regarding the influence of A-ring substitution pattern on the relative stability of the interconvertible N10-C11 carbinolamine, carbinolamine methyl ether, and imine forms of PBDs.
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
3
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1951-64
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Effect of A-ring modifications on the DNA-binding behavior and cytotoxicity of pyrrolo[2,1-c][1,4]benzodiazepines.
pubmed:affiliation
CRC Gene Targeted Drug Design Research Group, School of Pharmacy and Biomedical Sciences, University of Portsmouth, St. Michael's Building, White Swan Road, Portsmouth, Hants P01 2DT, U.K. david.thurston@port.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't