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Journal ArticleDOI

Benzopyrans. Part 30. Synthesis of substituted xanthones from 3-acyl-2-methyl-1-benzopyran-4-ones

07 May 1993-Tetrahedron (Pergamon)-Vol. 49, Iss: 19, pp 4127-4134
TL;DR: The xanthone as mentioned in this paper was derived from the base catalysed self-condensation of the chromone and showed that it can be obtained by refluxing with NaOMe in MeOH.
About: This article is published in Tetrahedron.The article was published on 1993-05-07. It has received 19 citations till now. The article focuses on the topics: Chromone & Pyran.
Citations
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Patent
28 Aug 2001
TL;DR: In this article, compounds of Formula (I) that inhibit DNA-dependent protein kinase, compositions comprising the compounds, methods to inhibit the DNA-PK biological activity, and methods to sensitize cells the agents that cause DNA lesions are disclosed.
Abstract: Compounds of Formula (I) that inhibit DNA-dependent protein kinase, compositions comprising the compounds, methods to inhibit the DNA-PK biological activity, methods to sensitize cells the agents that cause DNA lesions, and methods to potentiate cancer treatment are disclosed.

66 citations

Journal ArticleDOI
TL;DR: The chemistry and application of the title aldehyde and some simple derivatives thereof are reviewed in this paper, where the authors propose a simple derivative of the aldehydes, which they call simple aldeheeds.

42 citations

Reference EntryDOI
TL;DR: The Vilsmeier-Haack reagent can be used to form carbon-oxygen or carbon-nitrogen bonds, unless these are accompanied by formation of a carbon-carbon bond as mentioned in this paper.
Abstract: This chapter extends the discussion to reactions between the Vilsmeier-Haack reagent (subsequently referred to as the Vilsmeier reagent for brevity) and any other compounds in which a carbon-carbon bond is formed. The discussion thus excludes reactions in which the Vilsmeier reagent acts as a chlorinating agent (for example in the preparation of acid chlorides), or in which it forms carbon-oxygen or carbon-nitrogen bonds, unless these are accompanied by formation of a carbon-carbon bond. For a discussion of the nature of the reagent and of the mechanism of the reaction, the earlier chapter in vol. 49 should be consulted. There are also a number of reviews that deal at length with mechanisms of reactions involving the Vilsmeier reagent, notably those by Jutz and Marson, and hence this chapter will concentrate on applications, with brief mention of mechanisms when necessary. Wizinger has pointed out that alkenes could react with the Vilsmeier reagent, but his only examples were styrenes where the intermediate carbocation has considerable stability. Hydrolysis gives the cinnamaldehyde. In principle, any alkene which is not too sterically hindered can undergo this reaction, but the Vilsmeier reagent has low reactivity as an electrophile, and in practice activation is often necessary. The addition depends on the HOMO of the alkene, and anything increasing the HOMO energy will aid reaction, as for example further conjugation (dienes, trienes, etc.) or the presence of an electron-donating substituent. Hence aldehydes and ketones are active in their enol forms, and enol ethers and enamines are good substrates. Indeed, all additions covered by this chapter can be regarded as alkene additions, even those on active methyl groups attached to electron-deficient rings. As with any reaction involving carbocation intermediates, rearrangements are possible; the initial products are sometimes enamines, and this can give rise to polysubstitution. The substrates are grouped into eleven major subsections; references to reviews of particular relevance will be found in the appropriate subsection. Keywords: vilsmeier reaction; non-aromatics; alkenes; dienes; polyenes; heteroatoms; substituents; enamines; enamides; alkynes; aldehydes; ketones; imines; hydrazones; semicarbazones; oximes; carboxylic acids; anhydrides; acid chlorides; esters; lactones; amides; lactams; imides; nitriles; methyl groups; methylene groups; adjacent rings; comparison of methods; experimental conditions; experimental procedures; tabular survey

36 citations

Patent
19 Mar 2004
TL;DR: In this article, compositions comprising the compounds, methods of inhibiting the DNA-PK biological activity, and methods of sensitizing cells the agents that cause DNA lesions, and method of potentiating cancer treatment are disclosed.
Abstract: Compound that inhibit DNA-dependent protein kinase, compositions comprising the compounds, methods of inhibiting the DNA-PK biological activity, methods of sensitizing cells the agents that cause DNA lesions, and methods of potentiating cancer treatment are disclosed.

33 citations

References
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Journal ArticleDOI
TL;DR: Syntheses de benzo [b] xanthenes et de benzos as discussed by the authors, a partir de salicyloyl-6 ou 7 tetrahydro-1,2,3,4 naphtalenes
Abstract: Syntheses de benzo [b] xanthenes et de benzo [c] xanthenes a partir de salicyloyl-6 ou 7 tetrahydro-1,2,3,4 naphtalenes

11 citations