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Md. U. KHAN ET AL.
flash chromatography. IR (KBr, cmꢄ1): 3440 and 3178 (OH and NH), 2968 and 2975
=
=
(aliphatic C-H), 1713 and 1631 (C O), 1548 and 1493 (C C aromatic), 1451
(aliphatic C-H), 1242 (C-N), 1074 (C-O), 772 and 739 (Ar-H out of plane bend).
1H NMR (DMSO-d6, 300 MHz, d ppm): 2.47 (m, 4H, 2CH2), 3.48 (m, 4H, 2CH2),
7.90 (2d, J ¼ 8.8 Hz, 4H), 8.01 (2d, J ¼ 8.8 Hz, 4H), 8.15 (d, J ¼ 2.5 Hz, 1H), 8.51
(d, J ¼ 2.5 Hz, 1H), 8.70 and 8.74 (2 t, J ¼ 5.2 Hz, 2H), 18.89 (brs, 1H). 13C NMR
and DEPT (DMSO-d6, 300 MHz, d ppm): 34.2 (CH2), 35.9 (CH2), 113.7 (CH),
121.2 (C), 121.7 (CH), 122.2 (CH), 128.3 (CH), 128.8 (CH), 135.2 (C), 135.6 (C),
139.5 (C), 142.4 (C), 153.7 (C), 154.0 (C), 165.5 (C), 169.5 (C), 171.2 (C), 173.2 (C).
MS m=z (ESI): 577.2 [(MH)þ], 599.0 [Mþ þ Na].
5-[2-[40,5-bis[(2-Carboxyethyl)carbamoyl]biphenyl-2-yl]diazenyl]-2-
hydroxybenzoic Acid (Biphenyl-Azo Salicylic Acid, 7)
This related substance was prepared in laboratory as described in previous
example. IR (KBr, cmꢄ1): 3446 and 3180 (OH and NH), 2960 and 2971 (aliphatic
=
=
C-H), 1720 and 1635 (C O), 1552 and 1490 (C C aromatic), 1443 (aliphatic C-H),
1248 (C-N), 1076 (C-O), 775 and 731 (Ar-H out of plane bend). 1H NMR (DMSO-d6,
300 MHz, d ppm): 2.54 (m, 4H, 2CH2), 3.49 (m, 4H, 2CH2), 6.70 (d, J ¼ 8.8 Hz, 1H),
7.58 (d, J ¼ 8.5 Hz, 2H), 7.60 (dd, J ¼ 8.8 Hz and 2.5 Hz, 1H), 7.70 (d, J ¼ 8.8 Hz, 1H),
7.93 (d, J ¼ 8.5 Hz, 2H), 7.97 (dd, J ¼ 8.8 Hz and 1.4 Hz, 1H), 8.05 (d, J ¼ 1.4 Hz, 1H),
8.17 (d, J ¼ 2.5 Hz, 1H), 8.64 (t, J ¼ 5.2 Hz, 1H), 8.77 (t, J ¼ 5.2 Hz, 1H), 18.34 (brs,
1H). 13C NMR and DEPT (DMSO-d6, 300 MHz, d ppm): 34.6 (CH2), 36.5 (CH2),
116.9 (CH), 119.2 (CH), 119.9 (C), 126.2 (CH), 127.5 (CH), 128.6 (CH), 129.4
(CH), 130.4 (CH), 131.3 (CH), 134.0 (C), 135.6 (C), 138.7 (C), 141.9 (C), 143.5 (C),
151.8 (C), 166.4 (C), 166.8 (C), 171.1 (C), 173.8 (C). MS m=z (ESI): 549.2 [(MH)þ],
571.0 [Mþ þ Na].
3-[4-[5-[4-(2-Carboxy Ethyl Carbamoyl)phenylazo]-2-hydroxy
Phenylazo]benzoyl Amino] Propionic Acid (Bis-Azo Diacid, 8)
Concentrated hydrochloric acid (5 mL, ꢃ36% w=w) was added to a suspension
of N-(4-aminobenzoyl)-b-alanine (5 g, 0.024 mol) in DM water (75 mL) at 20–25 ꢂC,
and the resulting solution was cooled to 2 to ꢄ2 ꢂC. A solution of sodium nitrite
(1.74 g, 0.025 mol) in DM water (10 mL) was added at 2 to ꢄ2 ꢂC. The resulting
diazotized solution was added to a precooled solution of 4-hydroxybenzoic acid
(1.65 g, 0.012 mole) in DM water (100 mL) containing sodium carbonate (9.1 g) at 2
to ꢄ2 ꢂC, maintaining pH above 8. After completion of the reaction, the reaction mass
was acidified, filtered, washed with DM water, and dried. Thereafter, the obtained
product was suspended in aqueous acetic acid (400 mL) and refluxed for 20 min, then
cooled to 25–30 ꢂC, filtered, and dried to obtain impurity 8 (4.28 g, 32% yield). IR
(KBr, cmꢄ1): 3298 (NH), 3057 (Ar-H), 2921 (aliphatic C-H), 1630 and 1604 (C O),
=
=
1577 and 1538 (C C aromatic), 1430 (C-H), 1214 (C-N), 1085 (C-O), 799 and 772
1
(Ar-H out of plane bend). H NMR (DMSO-d6, 300 MHz, d ppm): 2.57 (m, 4H,
2CH2), 3.52 (m, 4H, 2CH2), 7.32 (d, J ¼ 8.8 Hz, 1H), 7.94 (d, J ¼ 8.2 Hz, 1H),
7.95–8.15 (m, 8H), 8.24 (s, 1H), 8.72 and 8.75 (2t, J ¼ 5.2 Hz, 2H), 11.54 (brs, 1H),
12.27 (brs, 2H). 13C NMR and DEPT (DMSO-d6, 300 MHz, d ppm): 33.7 (CH2),