SUBSTITUTED 3-R-7,8-DIHYDRO-2H-PYRROLO[1,2-а][1,2,4]TRIAZINO[2,3-с]QUINAZOLIN-5а-(6H)- ALKYL-CARBOXYLIC ACIDS - PROMISING CLASS OF LOW-TOXIC ANTI-INFLAMMATORY AGENTS

Abstract

The aim of the work. Evaluation of the anti-inflammatory activity and acute toxicity of new 3-R-7,8-dihydro-2H-pyrrolo[1,2-a][1,2,4]triazino[2,3-c]quinazolin-5a (6H)-alkyl-carboxylic acids as potential anti-inflammatory agents.

Materials and Methods. The study of anti-inflammatory activity was conducted on a model of carrageenan-induced paw edema on white male Wistar rats weighing 140- 220 g. The tested compounds were administered orally using an atraumatic probe at a dose of 25 mg/kg, sodium diclofenac was used as reference drug and was administrated in dose 10 mg/kg. The acute toxicity of the studied compounds was predicted by in silico methods (GUSAR and TEST software packages), as well, as evaluated experimentally on outbred white mice of both sexes weighing 16-24 g. The synthesized compounds were administered intraperitoneally in the form of a fine suspension in physiological saline, which was stabilized by Tween 80. Median lethal doses (LD₅₀) were determined by the Prozorovsky method. Statistical processing was conducted by appropriate approaches using the STATISTICA® for Windows 6.0 software (StatSoft Inc, No. AXXR712D833214FAN5).

Results and Discussion. The study of the anti-inflammatory activity of pyrrolo[1,2-a][1,2,4]triazino[2,3-c]quinazolines derivatives showed that the studied compounds are highly active anti-inflammatory agents, that compete or exceed activity of reference drug “Sodium diclofenac”. The most active was 3-(3-methyl-2,8-dioxo-7,8-dihydro-2H-pyrrolo[1,2-a][1,2,4]triazino[2,3-c]quinazolin-5a(6H)-yl)propanoic acid (5) which by the level of pharmacological effect exceeded reference drug by more than 20%. The results of in silico and in vivo study of the pyrrolo[1,2-a][1,2,4]triazino[2,3-c]quinazoline derivatives acute toxicity showed their mutual correlation. Intraperitoneal administration of the studied compounds to white mice at doses of 500 to 1500 mg/kg allowed assign them to toxicity classes IV and V (low-toxic and practically non-toxic compounds, respectively, classification of toxicity with parenteral routes of administration).

Conclusion. The anti-inflammatory activity and acute toxicity of new pyrrolo[1,2-a][1,2,4]triazino[2,3-c]quinazolines were studied. It was found that most of the studied compounds exhibit significant anti-inflammatory activity being low-toxic or practically non-toxic (IV-V class). “Chemical structure – anti-inflammatory activity” relationship analysis showed, that the introduction of propanoic acid moiety in position 5a may be considered as rational approach for search for new anti-inflammatory agents. Described compounds are a promising group for further purposeful synthesis and in-depth pharmacological studies aimed at creating new non-steroidal anti-inflammatory drugs.