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Journal of Thermal Analysis and Calorimetry
Authors:
Barbara Barszcz
,
Joanna Masternak
,
Maciej Hodorowicz
, and
Agnieszka Jabłońska-Wawrzycka

crystallize at room temperature. After 3 days, the colorless crystals were collected by vacuum filtration, washed with mother liquid and dried in a vacuum box. The products were collected in 53 and 86% yield, respectively. Anal. Calc. for: C 10 H 6 N 4 O 4

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.2 O6–H6O…N4 vi 0.93 1.95 2.859(3) 164.0 O21–H21O…N12 0.90 2

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d h 6.00 ± 0.00 4.00 ± 0.00 K e e ng/mL 0.12 ± 0

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Acta Chromatographica
Authors:
Yuping Shen
,
Minhui Xu
,
Peipei Deng
,
Qinying Gu
,
Huawu Yin
,
Guohua Xia
,
Xiaobin Jia
,
Huan Yang
, and
James Tam

prepared sample solution was injected immediately and then loaded after being stored at room temperature under shade for 2 h, 4 h, 6 h, 8 h, 24 h, 36 h, and 48 h. Then, the RSDs of their peak areas of were calculated

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-NMR (500 MHz, CDCl 3 ) δ 8.43 (d, J = 8.0 Hz, 1H, 5-H), 7.64 (t, J = 7.7 Hz, 1H, 7-H), 7.49 (d, J = 8.6 Hz, 1H, 8-H), 7.36 (t, J = 7.4 Hz, 1H, 6-H), 6.21 (s, 1H, 3-H), 5.42–5.26 (m, 4H, 6′, 7′, 9′ 10′-H), 3.72 (s, 3H, N-CH 3 ), 2.76 (t, J = 5

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region at δ H 6.75 ppm (1H, br s, H-7), δ H 7.06 ppm (1H, br s, H-2), δ H 7.36 ppm (1H, d, J = 2.5 Hz, H-5), and δ H 7.66 ppm ( 1H, d, J = 2.5 Hz, H-4), it also showed two singlets at δ H 2.46 ppm (3H, s, Me) and δ H 3.84 ppm (3H, s, O

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) Error (ppm) Formula 1 2.92 169.01425 169.01499 4.4 C 7 H 6 O 5

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Hz, H-9), 6.65–6.78 (3H, m, H-2’, H-5’, H-6’), 5.94 (2H, s, –O–CH 2 –O–); 13 C-NMR (CDCl 3 , 400 MHz): δ 197.20 (C-4), 191.12 (CHO-6), 168.28 (C-10), 167.17 (C-5), 164.80 (C-7), 148.05 (C-4’), 146.63 (C-3’), 130.87 (C-1’), 122.13 (C-6’), 109.42 (C-2

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] + ; 1 H-NMR (600 MHz, CDCl 3 ) δ : 7.48 (brs, 1 H), 7.34 (d, J = 8.79 Hz, 1 H), 7.32 (s, 2H), 6.85 (d, J = 2.05 Hz, 1 H), 6.78 (dd, J = 8.64, 2.20 Hz, 1 H), 5.06 (ddd, J = 11.64, 9.45, 4.98 Hz, 1H), 4.48 (br. s., 1H), 3.92 (s, 9 H), 3.91 (m, 1H

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