Peptide Nanofiber Templated Zinc Oxide Nanostructures as Non-precious Metal Catalyzed…
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Compound 6 (Table 3): δ H NMR (400 MHz, CDCl3) δ
7.99–7.98 (m, 1H), 7.82–7.81 (m, 2H), 7.47 (d, J=8.8, 2H),
2.77 (t, J=7.8 Hz, 2H), 1.34–1.31 (m, 4H), 0.914 (t, J=7.6,
2H). 13C NMR (100 MHz, CDCl3): δ=202.6, 162.4, 152.2,
138.6, 134.9, 128.3, 123.3, 115.0, 40.9, 30.0, 20.2, 13.8.
2.12 General Procedure for the Synthesis
of Quinazoline Tetracyclic Derivatives
A mixture of isatoic anhydride (1 mmol), amine (1 mmol)
and 0.625 mg of catalyst in PEG, was stirred at 100 °C.
After the reaction was completed, ninhydrin (1 mmol) was
added into the resulting mixture. Then the mixture was
heated at 100 °C and the reaction was monitored by TLC
for an appropriate time. After completion, the mixture was
cooled to room temperature and 20 mL of ethyl acetate
was added to the organic phase and washed with water,
dried over anhydrous Na2SO4, and filtered. The residue
was purified by column chromatography (silica gel, hex-
ane/ethyl acetate) to afford the corresponding product.
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Compound 8 (Table 6): H NMR (400 MHz, DMSO) δ
2.51–2.41 (m, 1H), 1.75–1.59 (m, 10H), FT-IR (KBr) νmax
/
cm−1:2927, 2858, 1726, 1655, 1475, 1429, 1374, 1302,
1255, 1185, 1075, 1019, 973, 899, 725, 680.
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Compound 9 (Table 6): H NMR (400 MHz, DMSO) δ
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8.4 (s, 1H), 8.17 (d, J = 8, 1H), 8.17 (d, J = 8, 1H), 7.92
(d, J = 8, 1H), 7.84 (q, J = 4.9, 2H), 7.69–7.63 (m, 1H),
7.55 (t, J = 7.2, 1H), 7.21 (q, J = 8.5, 1H), 3.36–3.32 (m,
1H), 1.48–1.37 (m, 14H). 13C NMR (100 MHz, CDCl3):
δ=186.8, 159.8, 147.8, 146.6, 139.9, 135.2, 134.6, 127.5,
127.4, 126.7, 123.4, 122.8, 121.9, 115.2, 40.6, 39.3, 26.4,
26.3, 25. FT-IR (KBr) νmax/cm−1:3056, 3020, 2923, 2846,
1711, 1656, 1609, 1403, 1153, 1100, 1022, 942, 821, 743,
676, 537, 463.
Compound 1 (Table 2): δ HNMR (CDCl3, 400 MHz):
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Compound 5 (Table 2): δ HNMR (CDCl3, 400 MHz):
(m, 5H), 6.95–6.88 (m, 1H) 6.4 (s, 1H), 4.2 (s, 3H).
Compound 3 (Table 4): 1H NMR (400 MHz, CDCl3) δ 9.9
3H), 7.35 (d, J=8, 1H), 7.03 (d, J=8.8, 1H), 3.69 (s, 2H).
Compound 4 (Table 4): 1H NMR (400 MHz, DMSO) δ 9.90
(s, 1H), 7.9 (s, 1H), 7.43–7.37 (m, 2H), 7.32–7.03 (m, 3H),
6.71–6.56 (m, 3H), 6.48–6.42 (m, 4H), 3.56 (s, 2H).
3 Results and Discussion
A schematic illustration of the preparation strategy of the
PNF) was shown in Scheme 1. Peptide 6 employed in this
report was synthesized by conventional solution phase meth-
odology. The C-terminus of amino acid was protected as
ethyl ester. Couplings were mediated by dicyclohexylcar-
bodiimide-1-hydroxybenzotriazole (DCC-HOBt). The final
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Compound 5 (Table 4): H NMR (400 MHz, DMSO) δ
6.48–6.44 (m, 3H), 3.40 (s, 2H).
Compound 1 (Table 6): 1H NMR (400 MHz, DMSO) δ 8.14
J=8.4, 2H), 7.55 (d, J=8.4, 2H), 7.41 (t, J=4.2, 2H), 4.44
(s, 2H), 13C NMR (100 MHz, CDCl3): δ = 180.8, 178.0,
145.0, 137.4, 137.7, 134.6, 133.6, 133.1, 127.1, 126.6,
126.5, 119.2, 117.6, 114.2, 41.1.
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compounds were purified and fully characterized by H
NMR and 13CNMR spectral studies. In this work, the effect
of phosphate buffer solutions on the structure of peptide
nanofiber was investigated. After the peptides nanofiber was
designed and synthesized Zn(NO3)2·3H2O was immobilized
on the surface of this nanostructural compound (Scheme 1).
The structure of the ZnO nanoparticles product was eluci-
dated on the basis of FT-IR, EDS, SEM, XRD, ICP-OES,
TEM and fluorescence spectroscopy. The FT-IR spectra pro-
vide valuable information regarding the nature of the func-
tional group attached to the metal atom. In order to study the
bending mode of the peptide nanofiber decorated with ZnO,
the IR spectrum of the peptide nanofiber was compared with
the peptide nanofiber decorated with ZnO. Peptide nanofiber
mainly exhibited four characteristic peaks at 1722, 1646,
1177, and 1067 cm−1, corresponding to (C=O), (N–H), and
(C–OH), respectively. However, the corresponding peaks of
peptide nanofiber/ZnO were changed to 1719, 1639, 1179,
and 1057 cm−1. The position and intensity of characteristic
Compound 4 (Table 6): 1H NMR (400 MHz, DMSO) δ 7.93
(q, J = 7.4 3H), 1.5 (t, J = 7.3 3H). 13C NMR (100 MHz,
CDCl3): δ = 188.9, 168.08, 147.0, 144.4, 142.7, 134.3,
131.8, 128.7, 128.6, 126.5, 123.7, 106.7, 28.6, 15.4. FT-IR
(KBr) νmax/cm−1: 3062, 3023, 2926, 2849, 1714, 1652, 1477,
1435, 1408, 1161, 1091, 1019, 726, 680, 527, 462.
Compound 5 (Table 6): 1H NMR (400 MHz, CDCl3) δ 8.17
7.17 (d, J=8, 2H), 2.77 (m, 1H), 1.32 (d, J=8, 6H). FT-IR
(KBr) νmax/cm−1:3024, 2924, 1708, 1630, 1503, 1511, 1408,
1312, 1249, 1033, 951, 901, 819, 737, 662, 540.
1 3