Pyrimidine annelated heterocycles - synthesis and cycloaddition of the first pyrimido[1,4]diazepine N-oxides
نویسندگان
چکیده
منابع مشابه
Bridgehead nitrogen heterocycles which contain the quinazoline moiety -- synthesis and cycloaddition of 1,2-dihydroquinazoline 3-oxides.
A novel synthesis of 1,2-disubstituted 1,2-dihydroquinazoline 3-oxides 8 and the first ever examples of 1,3-dipolar trapping of these nitrones to homonuclear dipolarophiles is described. The new dipoles 8 reacted with N-methyl maleimide, generating diastereomeric adducts 14-16. In the reaction between 8 and dimethyl acetylenedicarboxylate, primary cycloadducts 17 and/or stable rearrangement pro...
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Cycloaddition reactions of alkynes are elegant, atom-efficient transformations for the synthesis of carbo- and heterocycles, mostly aromatic, involving the construction of challenging skeletons of complex molecules. Therefore significant efforts have recently been devoted to the development of novel methodologies, efficient strategies and different catalytic systems to broaden the scope of thes...
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Preparation of a series of terminally and internally substituted delta-alkenyl and delta-alkynyl esters 6, 7 and 9, potential precursors to oxazin-2-one nitrones, has been attempted. Condensation between pyruvic or benzoylformic acid and the appropriate alcohol proceeded smoothly in some cases whilst allylic transposition was a major feature in other cases--most especially during reactions with...
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Saturated N-heterocycles are prevalent in biologically active molecules and are increasingly attractive scaffolds in the development of new pharmaceuticals. Unlike their aromatic counterparts, there are limited strategies for facile construction of substituted saturated N-heterocycles by convergent, predictable methods. In this Synopsis, we discuss recent advances in the synthesis of these comp...
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within the components of communicative competence, a special emphasis is put on the “rules of politeness,” specifically the politeness strategies (brown and levinson, 1978) that speakers deploy when performing the request speech act. this is because the degree of imposition that making a request places upon one’s interlocutor(s) has been seen to be influenced by several factors among which, as ...
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ژورنال
عنوان ژورنال: Journal of the Chemical Society, Perkin Transactions 1
سال: 2001
ISSN: 1472-7781,1364-5463
DOI: 10.1039/b007163n