Experimental antiulcer drugs. 1. Indole-1-alkanamides and pyrrole-1-alkanamides

Synthesis of Novel Aryl (4-Aryl-1H-Pyrrol-3-yl) (Thiophen-2-yl) Methanone Derivatives: Molecular Modelling, In Silico ADMET, Anti-Inflammatory and Anti-Ulcer Activities

BACKGROUND

Due to the presence of both five-membered heterocyclics like pyrrole and thiophene in one molecule considerable attention was made for their enormous pharmacological activities out of which include anti-inflammatory and anti-ulcer activities.

OBJECTIVE

Chalcones with toluenesulfonylmethyl isocyanide (TosMIC) undergo synthesis to form some new aryl (4-aryl-1H-pyrrol-3-yl) (thiophen-2-yl) methanone derivatives. Molecular docking of synthesized compounds with protein receptors of anti-inflammatory COX-1(3N8Y), COX-2 (1PXX) along with anti-ulcer H+/K+ATPase enzyme (2XZB) followed with drug-likeness, and in silico ADMET properties.

MATERIALS AND METHODS

The multicomponent reaction was carried out by the intermediate formation of α, β-unsaturated ketone from carbonyl compounds which on sequential addition undergoes [3+2] cycloaddition reaction in same medium affords aryl (4-aryl-1H-pyrrol-3-yl) (thiophen-2-yl) methanone derivatives by addition of TosMIC in basic medium had resulted in series of compounds PY1 to PY12. All the new synthesized compounds were screened for their in-vitro anti-inflammatory activity by bovine serum albumin method followe with COX assay, and in-vivo by using carrageenan-induced rat paw edema method of the selected compounds PY1, PY5 and PY12 which is also screened for anti-ulcer activity by pylorus ligation method, respectively. Molecular docking was performed using autodock tools, drug-likeness by OSIRIS property explorer and admetSAR properties.

RESULTS AND DISCUSSION

From the synthesized compounds of aryl (4-aryl-1H-pyrrol-3-yl) (thiophen- 2-yl) methanone derivatives PY5 showed decent in-vitro and in-vivo anti-inflammatory along selectivity index of 6.2 for COX-1 with IC50(μM) value of 9.54 over diclofenac with 8.74 and PY1 showed decent in-vivo anti-ulcer activities along with drug-likeness and in silico ADMET predictions revealed that all the synthesized compounds have minimal toxic effects with good absorption as well as solubility characteristics. The selected compounds may serve as potential lead compounds for developing new anti-inflammatory and anti-ulcer drugs.

CONCLUSION

From the newly synthesized molecules PY5 was found to be effective for anti-inflammatory and PY1 was found to be effective for anti-ulcer activities further derivitization and designed of modification to achieve more compounds with potent anti-inflammatory and anti-ulcer activities.

Cytoprotective effect of benzyl N'-(5-chloro-indol-3-yl-methylidene)-hydrazinecarbodithioate against ethanol-induced gastric mucosal injury in rats

Indolic compounds have attracted a lot of attention due to their interesting biological properties. The present study was performed to evaluate the subacute toxicity and anti-ulcer activity of BClHC against ethanol-induced gastric ulcers. Experimental animal groups were orally pre-treated with different doses of BClHC (50, 100, 200 and 400 mg/kg) in 10% Tween 20 solution (vehicle). Blank and ulcer control groups were pre-treated with vehicle. The positive group was orally pretreated with 20 mg/kg omeprazole. After one hour, all groups received absolute ethanol (5 mL/kg) to generate gastric mucosal injury except the blank control group which was administered the vehicle solution. After an additional hour, all rats were sacrificed, and the ulcer areas of the gastric walls determined. Grossly, the ulcer control group exhibited severe mucosal injury, whereas pre-treatment with either derivative or omeprazole resulted in significant protection of gastric mucosal injury. Flattening of gastric mucosal folds was also observed in rats pretreated with BClHC. Histological studies of the gastric wall of ulcer control group revealed severe damage of gastric mucosa, along with edema and leucocytes infiltration of the submucosal layer compared to rats pre-treated with either BClHC or omeprazole where there were marked gastric protection along with reduction or absence of edema and leucocytes infiltration of the submucosal layer. Subacute toxicity study with a higher dose of derivative (5 g/kg) did not manifest any toxicological signs in rats. In conclusions, the present finding suggests that benzyl N'-(5-chloroindol-3-ylmethylidene)hydrazinecarbodithioate promotes ulcer protection as ascertained by the comparative decreases in ulcer areas, reduction of edema and leucocytes infiltration of the submucosal layer.