A facile synthesis and heteroannulation of thiazolopyrimidine and related heterocyclic systems

Abstract

Reaction of pyrimidinylacetic acid 2 with different electrophilic and nucleophilic reagents gave annulated pyrimidine derivatives 3‐11, respectively. Compound 3 was transformed to pyrimidinylacetyl azide 12, which upon heterocyclization with active methylene compounds, acidic and basic reagents furnished functionally substituted heteroaromatic compounds 13‐21, respectively. The antimicrobial activity of some synthesized compounds was investigated. The structures of the synthesized derivatives were elucidated by elemental and spectral analyses.

Behaviour of 4,6-Diaryl-2(1H) pyrimidine-2-thiones Towards Some Electrophiles and Nucleophiles

“…Treatment of compounds 3a, 3b with glacial acetic acid conc. HCl mixture affected cyclization to the corresponding 6,8-diaryl-3,4-dihydro-2H,6Hpyrimido[2,1-b][1,3]-thiazin-2-ones 9a,9b, this is in agreement with the previous findings of Aly, et al (18) , respectively. This was confirmed by elemental analysis (Table 1) and spectral data (Table 2).…”

Synthesis of Some Novel Thiazolo[3,2‐a]pyrimidine and Pyrimido[2,1‐b][1,3]thiazine Derivatives and their Antimicrobial Evaluation

“…Condensation of the latter with benzaldehyde and sodium acetate resulted in the formation of 2-(2benzylidene-3-oxo-7-(4-phenoxyphenyl)-5-(thiophen-2-yl)-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidin-6-yl) acetic acid (4), which in turn reacted with hydroxylamine hydrochloride in pyridine to give thiazolo[3,2-a]pyrimidine 5 [31] (Scheme 2). IR spectrum exhibited absorption bands at 1690, 3415-3225, and 1690 cm À1 corresponding to NH, OH, and CO groups, respectively.…”

Synthesis of New Peptidyl- and Glycosylpyrimidine Derivatives

“…Refluxing of compound 6 with thionyl chloride on a water bath for 2h gave pyrimidinyloxyacetyl chloride 7a, which was in situ treated with sodium azide 28 to yield the corresponding pyrimidinyloxyacetyl azide 7b. Recently, there has been a growing interest in the synthesis of peptides for medicinal applications.…”