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.

Communication | Special issue | Vol 8, No. 1, 1977, pp.263-268
Published online, 1st January, 1970
DOI: 10.3987/S(S)-1977-01-0263
A Novel Ring Expansion Reaction of 4-Aminoantipyrines to 5-Amino-4(3H)-pyrimidinones

Taisei Ueda,* Noriichi Oda, and Isoo Ito

*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan


4-Amino(or anilino)antipyrines (I, II) were transformed into 5-amino(or anilino)-4(3H)-pyrimidinones (III, IV) in the presence of bases such as sodium hydride, sodium amide, sodium hydroxide, or sodium ethoxide in refluxing xylene. Treatment of III with hydrazine hydrate gave 4-anilino-5-hydroxy-3-methylpyrazole (V). However, the reaction of IV with hydrazine hydrate gave 3,5-diamino-6-methyl-4(3H)-pyrimidinone (VII) and 4-(5-oxo-3-methyl-pyrazolinyliden-4-amino)-5-hydroxy-3-methyl-pyrazole (VIII).