Synthesis and conversion of 6‐fluoro derivatives of 1,3,4‐thiadiazolo‐[3,2‐a]pyrimidine

Abstract

in Wiley Online Library (wileyonlinelibrary.com).2-Alkyl-, 2-aryl-, and 2-halo-substituted derivatives of 7-methyl-6-fluoro-1,3,4-thiadiazolo[3,2-a]pyrimidin-6-one (3) were prepared by reaction of 2-substituted 5-amino-1,3,4-thiadiazoles (1) and ethyl 2-fluoroacetoacetate (2) in polyphosphoric acid. A convenient procedure was developed for the synthesis of new 2-amino derivatives of 2-R-7-methyl-6-fluoro-1,3,4-thiadiazolo[3,2-a]pyrimidin-6-one (5).

Synthesis of Novel Benzothiazolo[3,2‐a]pyridimidin‐4‐ones with Potential Cytotoxic and Pro‐Apoptotic Potential

“…For our investigation, we chose chloro‐functionalized benzothiazolo[3,2‐ a ]pyrimidin‐4‐one 1 as a readily available starting material . Compound 1 was synthesized by condensation of commercially available 2 ‐ amino ‐ 6 ‐ chlorobenzothiazole with ethyl acetoacetate (Scheme ) …”

“…For our investigation, we chose chloro-functionalized benzothiazolo[3,2-a]pyrimidin-4-one 1 as a readily available starting material. [19][20][21][22][23][24] Compound 1 was synthesized by condensation of commercially available 2-amino-6-chlorobenzothiazole with ethyl acetoacetate (Scheme 1). [19][20][21][22][23][24][25][26][27][28][29][30] We started our investigation by optimizing the conditions of the Suzuki-Miyaura reaction of 1.…”

“…It is important to note that simple nucleophilic aromatic substitution (S N Ar), in the absence of a Pd catalyst, did not give the desired product ( Table 3, entry 8). [21] The preparative scope was next studied. The reaction of 1 with morpholine and various anilines afforded products 3a-e in good yields (Table 4).…”

Synthesis and transformations of hydrazine substituted 6‐fluoro derivatives of 1,3,4‐thiadiazolo[3,2‐a]pyrimidine

“…5 H ‐2‐Bromo‐6‐fluoro‐7‐methyl‐1,3,4‐thiadiazolo[3,2‐ a ]pyrimidin‐5‐one was obtained according to the ref. 15.…”