97693-29-3Relevant academic research and scientific papers
Synthesis and Dimroth rearrangement of 6-cyano-1,2,4-triazolo-[4,3-a]pyrimidin-5- and 7-ones. A novel alkylation with orthoesters and a new participation of the cyano group in the rearrangement
El Ashry,El Kilany,Rashed,Mousaad,Assafir
, p. 1203 - 1212 (2007/10/03)
The cyclization products of 5-cyano-2-hydrazino-6-phenyl-3,4-dihydropyrimidin-4-one (6) with one carbon inserting agents have been confirmed to be of the 1,2,4-triazolo[4,3-a]pyrimidin-5(8H)-ones type and not the respective 7-ones, by comparing their alkylated derivatives 10a, 11a, 27 and 28 with the product from the cyclization of the 3-methyl and 3-benzyl derivatives of 6. A novel alkylation process was found when triethyl orthoformate was used as a cyclizing agent. Dimroth rearrangement of 8, 14, 15, 24, 34 and 36 with 2% ethanolic KOH gave the respective triazolo[1,5-a]pyrimidinone 13, 18, 19, 25, 38 and 40, respectively. Using 10% ethanolic KOH led to a novel participation of the cyano group in the rearrangement whereby 8a gave 7-imino-5-phenyl-1,2,4-triazolo[1,5-a]pyrimidine 22.
NEW PYRIDINE DERIVATIVES: SYNTHESIS AND APPLICATION OF THIAZOLO-TRIAZOLO-PYRIMIDINE AS BACTERICIDES, FUNGICIDES AND BIOREGULATORS
Khalil, Zarif Hallem,Hafez, Ali Ahmed Abdel,Ahmed, Ahmed Abdo
, p. 81 - 94 (2007/10/02)
5-Cyano-4-oxo-6-phenyl-2-thioxo-1,2,3,4-tetrahydro pyrimidine (I) reacts with alkyl or alkaryl halides to give the corresponding 2-alkyl (alkaryl) derivatives (IIa-g); and with chloroacetic acid ethyl chloroacetate to give compounds III and IV respectively further reaction of IV with ammonia and amines yielded 5-cyano-2(glycolamidethio)-6-phenyl pyrimidine-4(3H) one derivatives (Va-g).The parent thiazolopyrimidine (VI) was prepared from compound III by refluxing with acetic anhydride.Also compound I reacted with hydrazine hydrate to give 2-hydrazino derivative IX was converted into a variety of triazolo pyrimidine derivatives.The biological activity of the new compounds was tested as microbicidal and bioregulator agents, the results obtained were correlated with their structure.Key words: Pyrimidinethione; thiazolopyrimidine; triazolopyrimidine; synthesis and reactions; biological activity.
A One-Step Synthesis of 2-Methylthio-6-oxopyrimidine Derivatives: Preparation of Fused Pyrimidinones
Hussain, S. M.,El-Barbary, A. A.,Mansour, S. A.
, p. 169 - 171 (2007/10/02)
Condensation of a ternary mixture of ethyl cyanoacetate, S-methylisothiourea and aromatic aldehydes in pyridine afforded directly the 4-aryl-5-cyano-6-oxopyrimidines IV in good yields.Alkylation of IV with alkyl halides in alkaline medium yielded the 1-al
