Synthesis of N-[1-(2-nitrophenyl) 3-Cyano -4,5-diphenyl-1H-pyrrol-2-yl)-acetamides.(A):

The appropriate aminopyrrole, 1a (3.35 g, 0.01 mol), in acetic anhydride (40 mL) was refluxed for 5 h, cooled, poured onto ice-water, neutralized with ammonia to give compound N-[1-(2-nitrophenyl) 3-Cyano -4,5-diphenyl-1H-pyrrol-2-yl)-acetamides, respectively in the form of precipitates which were filtered off, dried, and recrystallized from methanol.

Synthesis of N-[1-(4-nitrophenyl) 3-Cyano -4,5-diphenyl-1H-pyrrol-2-yl)-acetamides.(B):

The appropriate aminopyrrole, 1b (3.20 g, 0.01 mol), in acetic anhydride (40 mL) was refluxed for 5 h, cooled, poured onto ice-water, neutralized with ammonia to give compound N-[1-(4-nitrophenyl) 3-Cyano -4,5-diphenyl-1H-pyrrol-2-yl)-acetamides, respectively in the form of precipitates which were filtered off, dried, and recrystallized from methanol.

Synthesis of 3-[2-amino-1- (p- nitro phenyl)-4,5-diphenyl-1H-pyrrole)amidoximes (C):

The appropriate cyanopyrrole 1a(3.49 g, 0.01 mol) , hydroxyl amine hydrochloride (0.33 g, 0.01 mol) and anhydrous sodium carbonate (5.3 g, 0.05 mol) in absolute ethanol (40 mL) was refluxed for 4 h, filtered while hot and the residue was washed with hot ethanol. The collected filtrate was cooled, poured onto ice-water to yield precipitates, which were filtered, dried, and recrystallized from methanol, to give compound.

Synthesis of 2-amino-1-(o-nitrophenyl)-4,5-diphenyl-3-tetrazolo-1H-pyrroles.(D):

A mixture of the appropriate cyanopyrrole 1b (3.35 g, 0.01 mol), sodium azide (0.65 g, 0.01 mol) and ammonium chloride (1.06 g,0.02 mol) was refluxed in DMF (30 mL) for 4 h, filtered while hot and the residue was washed with hot DMF. The collected filtrate was concentrated, cooled, poured onto ice-water to yield precipitates, which were filtered, dried and recrystallized from methanol, to give compound.

Synthesis of 5,6-diphenyl-7-(p-nitro phenyl)-7H-pyrrolo [2,3-d]pyrimidin-4(3H)-ones (E):

An appropriate aminopyrrole, 1a (3.35 g, 0.01 mol), in formic acid (20 mL, 85%) was heated under reflux for 3 h, cooled, poured onto ice-water to give compounds in the form of precipitates which were filtered off, dried, and recrystallized from ethanol.

MATERIAL AND METHOD:

1) All chemicals and solvents were procured from commercial sources, purified and dried using standard procedures from literature whenever required .the reagents were purchased from Samarth lab ,loba research lab ,raj lab and issued from Rajarambapu College of Pharmacy, Kasegaon.

2) Melting points were determined by open capillary tube method and are uncorrected.

3) Thin layer chromatography was used to assess the course of reaction and the purity of the intermediates and the final compound were confirmed by applying a single spot on TLC plate (silica gel G) using various solvents such as toluene (T), ethyl acetate ( E), water (w) systems .

4) TLC plates were visualized using iodine chamber.

5) IR spectra were recorded using KBR disc on Jasco FTIR-410.H¹NMR spectra were performed in DMSO solution and their chemical shift are reported in δ unit with respect to TMS as internal standard at Shivaji University, Kolhapur. Mass spectra were obtained from Shivaji University, Kolhapur.

Anti-inflammatory activity⁽⁴⁾

Rat paw edema assay was carried out according to Winter et al. Prepared compounds (equimolar to the reference drug) were dissolved in DMSO and administrated subcutaneously. One hour later, paw edema was induced by subplantar injection of 0.1 mL of 1% carrageenan (Sigma Aldrich, St. Louis, USA) into the right hind paw. Paw volume was measured using a water plethysmometer (Basile, Comerio, Italy). The difference between the right and left paw volume was measured at 1, 2, 3 and 4 h after induction of inflammation. Control group (five rats per group) received DMSO subcutaneously and carrageenan in subplantar region. Results were expressed as percentage inhibition of inflammation. Ibuprofen (70 mg/kg) was used as the reference drug.

RESULTS AND DISCUSSION:

All synthesized compounds were identified by IR and NMR. The synthesized compounds were assessed for their anti-inflammatory activity. As indicated in Table 1and 2. Compounds A, B, C, D, induced a good anti-inflammatory activity, comparable with that of ibuprofen. Their activity profiles were the same as ibuprofen (response increasing by time).Compound E showed the opposite profile. Compound C exerted a stronger anti-inflammatory effect than ibuprofen (69.3% inhibition at 4 h interval post carrageenan). Likewise, compounds A, B and D showed a significantly higher inhibitory action at the 4 h interval, especially, compound B (67.3% inhibition).

Graph of % inhibition of edema-

Table no. 1- Anti-inflammatory activity of synthesized compounds-

Sr.no.	Compound	Mean change in paw volume (ml)±SEM
Sr.no.	Compound	0Hr	1Hr	2Hr	3Hr	4Hr
1	Control	0.053±0.01	0.23±0.03	0.49±0.009	0.41±0.009	0.58±0.046
2	Ibuprofen	0.046±0.01	0.09±0.006	0.14±0.006	0.13±0.01	0.123±0.021
3	A	0.046±0.015	0.156±0.03	0.226±0.009	0.24±0.01	0.333±0.043
4	B	0.05±0.005	0.133±0.009	0.196±0.02	0.226±0.02	0.213±0.020
5	C	0.05±0.005	0.146±0.02	0.203±0.04	0.22±0.04	0.2±0.003
6	D	0.05±0.009	0.173±0.01	0.263±0.003	0.276±0.01	0.23±0.015
7	E	0.046±0.009	0.123±0.02	0.15±0.01	0.206±0.003	0.276±0.01

Table no. 2- % Inhibition of edema-

	% Inhibition of edema
Treatment	0hr	1hr	2hr	3hr	4hr
Ibuprofen	12.5	57.97	65.32	73.37	81.12
A	12.5	31.88	45.16	53.24	48.58
B	7.67	42.02	52.41	57.14	67.34
C	8.46	36.23	50.80	57.14	69.38
D	6.10	24.63	36.29	46.10	64.79
E	12.33	46.37	63.70	59.74	57.65

Table no.3- IR and NMR analysis of synthesized compounds-

Compound

IR Cm^-1

NMR(ppm)

3410 (NH)

2225 (CN)

1712 (C=O)

2.06 (s, 3H, CH3-C=O) ,

6.9–7.9 (m, 14H, Ar-H), 8.1 (s, 1H, NH, D2O

exchangeable

2223 (CN)

3423 (NH)

1717 (C=O)

2.12 (s, 3H, CH3-C=O),

6.9–7.9 (m, 14H, Ar-H), 8.3 (s, 1H, NH, D2O exchangeable

3423 (NH)

2223 (CN)

1717 (C=O)

2.1 (s, 3H, CH3-C=O),

6.8–7.9 (m, 14H, Ar-H), 8.1 (s, 1H, NH, D2O

exchangeable)

3423 broad (O-H)

1446 (C-O)

5.2 (s, 1H, OH, D2O exchangeable),

5.9 (br s, 2H, NH2, D2O exchangeable),

6.7–8.1 (m, 14H, Ar-H), 8.8 (s, 1H, NH, D2O exchangeable),

8.9 (s, 1H, NH, D2O exchangeable)

3382 (N-H)

3526, 3445 (NH2)

1510(C-O)

5.2 (s, 2H, NH2, D2O

exchangeable), 6.7–7.8 (m, 14H, Ar-H),

8.36 s, 1H, NH, D2O exchangeable)