SU1455610A1 - Method of producing 6-aryl-5-oxy-2,3-dihydropypiridazine-3-ons - Google Patents

Abstract

The invention relates to heterocyclic compounds, in particular to the preparation of 4-hydroxy-6- (4-methylphenyl) -2,3-dihydropyridazin-3-one and 4-hydroxy-6-phenyl-2,3-dihydropyridazin-3-one which can be used as biologically active compounds. The goal is to get new connections in a new way. Obtaining the target compounds are from 2-benzoylmethylidenehydrazone 5- (4-methylphenyl) - or 5-phenyl-2,3-dihydrofuran-2,3-dione by recycling under the action of hydrochloric acid in dioxane, at 40-50 ° C, OVER 20-24 Ch. BRUTTO FOR-LA

OUTPUT %

M.P., ° C. FOR CONNECTION 1 C ₁₁ H ₁₀ N ₂ O ₂

63

276-277

FOR CONNECTION 2 C ₁₀ H ₈ N ₂ O ₂

58

268-269.

Description

The invention relates to a new method for producing new b-aryl-4-oxy-2, 3-digIdropyridazin-3-ones of the general formula I

where R = H, CH ₃ ). which may find application as biologically active soybeans. movements, in particular anticonvulsants.

The aim of the invention is a new method for producing new b-aryl-4-oxy-2, 3-dihydropyridazin-3-ones.

The goal is achieved by recycling

5-aryl-2,3-dihydrofurac-2,3-dione 2-benzoylmethylidenehydrozone in aqueous dioxane under the action of chloro. • 2 hydrogen acid for 20-24 '.h at 40-50 ° C. · -,

Example 1. Getting 4-hydroxy. -6- (4 ^< -methylphenyl) -2,3-dihydropyridazin-3-one (1a).

A mixture of 3.18 g (0.01 mol) of 2-benzo-ylmethylidenehydrazone 5- (4-methylphenyl.. Nyl) -2,3-dihydrofuran-2., 3-dione, 50 ml of dioxane and -10 ml of 15% hydrochloric acid is heated with stirring at a temperature of 50 ° C /. for 20 hours. The reaction mixture was evaporated, the residue was recrystallized from acetone. Yield 1.27 g (63Z), mp 276-277 ° C.

Found, 2g C 65.5C H 5.17 _έ 'N14.03.

C p N

Calculated,%: C 65.34; H 4.98

N, 13.85.

, SU „„ 1455616 A1

IR spectrum, new paste); 1615 (C = N),

Spectrum ΠΜΡ, ό, M.D. (DsC), SO: 2.32 (s, 3H, CH4 7.13 (s, 1H, CH) 7.48. (Q, 4H, C ₄ H ₄ ), 7.88 (s, 1H, NH), 12.98; (broad, s, 1H, OH).

Example 2. Preparation of 4-hydroxy-6-phenyl-2, 3-dihydropyridazin-3- * she (16).

A mixture of 3.04 g (0.01 mol) of 5-phenyl-2,3-> dihydrofuran-2,3-dione 2-benzofchethenylidenehydrozone, 50 ml of diocane and .10 ml of 10% hydrogen chloride is heated with stirring at a temperature of 40 ° C for 24 hours. The reaction mixture was evaporated, the residue was crystallized from acetone. Yield 1.09 g (58%); mp. 268-9 ° C.

Found,% ί

15.09.

With ₁₀ HgNjO ^.

Calculated, 14.89.

IR, paste): 3340 (C = N).

. PIR spectrum, ppm, in (D ₃ C) xS0: |, 25 (s, 1H, CH); 7.60 (m, 6P, C ₅ H _b A NH.); 13.14 (br., S., 1H, OH).

Carrying out the reaction at lower temperatures lengthens the reaction time, and increasing the temperature leads to: Reduces the yield of the target products.

Example 3. Synthesis of 4-ox.i-b * (4-methylphenyl) -2, 3-Digi ^ ropyridazin 3-Z-one (1a).

The synthesis is carried out in the same amount of reagents, but at 25 ° C. After: 20 h, the yield of the product is .0.65 G (32%). An increase in the reaction time to 70 h allows 1.11 g (55%) of the substance to be isolated.

Pramer .4, Synthesis of 4-hydroxy-b “(4-methinphenyl)“ 2 ₉ 3-dihydropyridazin-3-one (1a). . ,

The synthesis is carried out in the same amount of reagents, but the reaction mixture is heated at 70 ° C for

J, cm ' ¹ , (in vasel 3332 (ΝΗ); 1678 (С = 0), s <

ri:

C 64.01; Η 4.13;

%: C 63.83; Η 4.29;

Y, cm ' ⁵ (in vaseline (ΝΗ), 1680 (C = 0), 1625

Editor L. Gerasimova is completing. Education yield 0.91 g (45%). reactions are fixed by

h. Synthesis of the product, Finishing data thin-layer chromatography ·.

Thus, the temperature regime and the time interval selected for the synthesis is optimal.

The synthesized compounds have an anticonvulsant effect according to the maximum electroshock test when administered intraperitoneally to white mice. Thus, compound 16 provides protection for 16% of mice against electroshock at doses of 10-30 mg / kg. Its acute toxicity is 200 mg / kg.

The inventive method for producing 6-aryl ~ 4-hydroxy-2,3-dihydropyridazine “Z-ones can be preparative find application in · organic chemistry.

Claims (1)

Claim The method of obtaining b-aryl-4-hydroxy-2, 3-dihydrop11ridazin-3-ones of the general formula OH in that where R = H, CH is distinguished by the fact that 2-benzenemethylidenhydrazone 5-aryl-2,3-dihydrofuran-2., 3-dione of the general formula where R has the above meaning,. subjected to recycling under the action of hydrochloric acid in dioxane at a temperature of 4050 ° C for 20-24 hours, followed by isolation of the target product by known methods.