Heterocyclic analogs of xanthones

Novel fluoro-substituted benzo- and benzothieno fused pyrano[2,3-c]pyrazol-4(1H)-ones

“…Full and unambiguous assignment of all 1 H, 13 [27]. The latter experiments were indispensable for the unambiguous mapping of some long-range 13 C, 1 H coupling constants.…”

“…In compounds A one benzene system of the parent xanthone is replaced by a pyrazole system whereas ring H is a heteroaromatic moiety or a benzene ring. Some representatives of the latter chromeno [2,3-c]pyrazol-4(1H)-ones (H = benzene) are already known and have been primarily described by Sarenko et al [13]. Type A compounds are interesting for medicinal chemists, as an example the A 2 -subtype specific adenosine receptor antagonist Bcontaining a substituted pyrazole system -may serve ( Fig.…”

“…Moreover, extensive NMR spectroscopic studies ( 1 H, 13 C, 15 N, 19 F) with the title compounds are showcased as well as their potential to act as precursors for the synthesis of higher condensed systems of biological interest.…”

“…Treatment of 5-fluorochromeno [2,3-c]pyrazol-4(1H)-ones with methylhydrazine afforded novel tetracyclic ring systems such as 2-methyl-7-phenyl-2,7-dihydropyrazolo[4 0 ,3 0 :5,6]pyrano [4,3,2-cd]indazole. Detailed NMR spectroscopic investigations ( 1 H, 13 C, 15 N, 19 F) with the obtained compounds were undertaken.…”

The Structure of 4‐Benzoyl‐5‐methyl‐2‐phenylpyrazol‐3‐one Oxime and Its Methyl Derivatives

“…Compounds 2 [11,12] and 3 [12,13] are known, but a more convenient synthesis of 2 was possible by reacting 1 with methyl 4-toluenesulfonate (TosOMe). The synthesis of oximes 4,…”