3-(2'-NAPHTHOYLMETHYLENE)-PIPERAZINONE-2 AND 1-N-PHENYL-3-PHENACYLIDENEPIPERAZINONE-2 SHOWING ANTIINFLAMMATORY ACTIVITY Russian patent published in 1996 - IPC

FIELD: organic chemistry. SUBSTANCE: products: 3-(2'-naphthoylmethylene)-piperazinone-2 (I) and 1-N-phenyl-3-piperazinone-2 (II) of the formula R¹ where: (I) C₆H₅: R - 2-naphthyl; R' - H; (II) R¹: R - C₆H₅.; R' - . Synthesis is carried out by interaction of acylpyruvic acids with ethylenediamine and N-phenylethylenediamine, respectively, at heating in ethanol medium in the presence of catalytic amount of acetic acid by the following scheme: where (I) C₆H₅: R - 2-naphthyl; R' - H; (II) R¹: R - C₆H₅; R' - C₁₆H₁₄N₂O₂.. (I): yield is 78.4%, m. p. is 241-242 C. Found, %: C - 72.32; H - 5.17; N - 10.56; empirical formula is T_пл. Calculated, %: C - 72.17; H - 5.29; N - 10.52. (II) : yield is 68%, m. p. is 140-141 C. Found, %: C - 73.80; H - 5.39; N - 9.72; empirical formula is C₁₈H₁₆N₂O₂.. Calculated, %: C - 73.95; H - 5.52; N - 9.58. Synthesized compounds show antiinflammatory activity: 45% for (I) and 51% for (II) T_пл. Toxicity LD₅₀ is above 1000 mg/kg. EFFECT: improved method of synthesis. 1 tbl