Synthesis and Preliminary Biological Properties Assessment of Novel 2-S-, 4, 5-Substituted and Bicyclic Derivatives of 6-Methylpyrimidine-4-ol

• Published in: Letters in organic chemistry Vol. 17; no. 2; pp. 149 - 156
• Main Authors: Yengoyan, Aleksandr P., Azaryan, Zhermen A., Pivazyan, Vergush A., Ghazaryan, Emma A., Tamazyan, Rafael A., Ayvazyan, Armen G.
• Format: Journal Article
• Language: English
• Published: SHARJAH Bentham Science Publ Ltd 01.01.2020
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; 5-oxypyridazinyl-pyrimidine; plant growth stimulant activity; 2-mercapto-6-methylpyrimidine-4-ole; 2-thiopyrazolylpyrimidines; THIAZOLOPYRIMIDINE; PYRIMIDINE; heterocyclization; 4-triazolylpyrimidines; 4-aminotriazolyl-pyrimidines; thiazolo[3,2,a]pyrimidine
• ISSN: 1570-1786; 1875-6255
• DOI: 10.2174/1570178616666190411110415

A series of novel 2-S-, 4-, 5-substituted and bicyclic 6-methylpyrimidine-4-ol derivatives including pyrazole, 1,2,4-triazole and pyridazine moieties in the molecule were synthesized by accessible and efficient methods. Thiopyrazolyl derivatives were obtained from 2-mercapto-6-methylpyrimidin-4-ol. 4-Triazolyl and 4-aminotriazolylpyrimidines were synthesized from the quaternary ammonium salt of pyrimidine and 4-chloro-substituted 2-thiomethyl-6-methylpyrimidine, respectively. The reaction of potassium salt of 1-methyl-6-oxo-1,6-dihydropyridazin-3-ole with ethyl 2-chloro-3-oxobutanoate and subsequent treatment with thiourea led to 6-((4-hydroxy-2-mercapto-6-methylpyrimidin-5-yl)oxy)-2-methylpyridazin-3 (2H)-one. The reaction product of the latter with 3-chloropentan-2,4-dione was subjected to heterocyclization, which afforded the target bicyclic derivative of pyrimidine. The synthesized compounds showed a pronounced stimulating action on plants growth. Their growth stimulant activities were in the range of 60-93% compared to heteroauxin.