Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact:

Price: ¥ 4,400 (Yen only)
Period: This Article can be accessed for 7 days.

Report | Regular issue | Vol 23, No. 5, 1985, pp.1135-1141
Published online, 1st January, 1970
DOI: 10.3987/R-1985-05-1135
New Synthesis of Pyrido[2,3-d]pyrimidines. I. Reaction of 6-Alkoxy-5-cyano-3,4-dihydro-2-pyridones with Guanidine and Cyanamide

Pedro Victory,* Rosa Nomen, Octavio Colomina, Miquel Garriga, and Ana Crespo

*Departmento de Química Orgánica, Instituto Químico de Sarriá, Universitat de Barcelona, 08028 Barcelona, Spain


The first step of a new synthesis of pyrido[2,3-d]pyrimidines, the substitution of the enolic alkoxyl group of 6-alkoxy-5-cyano-3,4-dihydro-2-pyridones (2) by guanidine and cyanamide is described. By this procedure a series of 2,4-diamino-5,6-dihydropyrido[2,3-d]pyrimidin-7(8H)-ones (6) and 6-cyanamino-5-cyano-3,4-dihydro-2-pyridones (3) have been synthesized. Products 3 have been isolated in this work for the first time, and tautomeric equilibrium with the cyanimino form has been detected in every case.