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Synthesis of Spiropyrimidodiazepines and Spirodiazepinopurines by Tandem Nitroso-ene/Diels–Alder Reactions

✍ Scribed by Fang-Li Zhang; Andrea Vasella

Publisher: John Wiley and Sons
Year: 2007
Tongue: German
Weight: 389 KB
Volume: 90
Category: Article
ISSN: 0018-019X
DOI: 10.1002/hlca.200790238

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✦ Synopsis

Abstract

New spirocyclic heterocycles 8, 16, 19/20, 25, 27, and 30 derived from pyrimido[4,5‐b][1,4]diazepin]‐8′(9′H)‐one were synthesised by a tandem nitroso‐ene/Diels–Alder reaction of 4‐(alkenoylamino)‐5‐nitrosopyrimides. The crystal structure of 16 was established by X‐ray analysis. It is characterised by four pairs of intermolecular H‐bonds linking every two molecules in the unit cell. Sequential imine reduction and intramolecular condensation of the C(4′)‐(acylamino)‐pyrimido[4,5‐b][1,4]diazepines 27 and 30 led to the [1,4]diazepino[1,2,3‐gh]purines 28/29 and 31, respectively.

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