Download PDF
Synthesis 1993; 1993(1): 145-148
DOI: 10.1055/s-1993-25819
paper
© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Preparation of Pyrazolo[3′,4′ : 4,5]pyrido[2,3-d]pyrimidines by the Intramolecular Reaction of Azomethine Imines in a 2,4(1H,3H)-Pyrimidinedione System

Michihiko Noguchi* , Kazuo Yamada
  • *Department of Applied Chemistry, Faculty of Engineering, Yamaguchi University, Tokiwadai, Ube 755, Japan
Further Information

Publication History

Publication Date:
17 September 2002 (online)

  PDF Download  Permissions and Reprints All articles of this category

A facile synthetic route to substituted 6,8-dimethyl-3,3a,4, 5-dihydro-2H-pyrazolo[3′,4′:4,5]pyrido[2,3-d]pyrimidine-] 7,9(6H,8H)-di-ones is described based on an intramolecular azomethine imine cyclization followed by dehydrogenation. The azomethine imine intermediates are given by the thermal 1,2-hydrogen shift of the hydrazones, which are formed from the reaction of 6-allylamino-5-formyl-1, 3-dimethyl-2,4(1H,3H)-pyrimidinediones and hydrazines 2.