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芹芹821

木虫 (正式写手)

我叫“费米“！！

应助: 0 (幼儿园)
金币: 2453.4
帖子: 410
在线: 101.8小时
虫号: 495205
注册: 2008-01-14
性别: MM
专业: 合成药物化学

[求助] 寻求一家C18液相制备的外包公司。

虫友们好，最近实验遇到了些问题，需要进行外包，但不知道谁能完成，特此开贴征询答案。你只需把你知道的，可能会做该项工作的机构告诉我即可。如能成，将会追加金币奖励！

具体的实验内容如下：
(6R,7S)-7-[(Z)-2-(2-Amino-4-thiazolyl)-2-(hydroxyimino)acetamido]-8-oxo-3-vinyl-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicAcid (3)
To a suspension of cefdinir (2.5 g) in water (25mL) was added 1 g of sodium bicarbonate to dissolve, 5 mL of 8%NaOH aqueous solution was added, and the mixture was stored at50 °C for 15 min. The mixture (3 mL) was placed on a preparativeODS silica gel column (10 2.0 cm, Octadecyl C18 I-40, 40 ím,Yamazen Co., Ltd., Osaka, Japan) and eluted with citrate-phosphatemonitored by HPLC-3 was collected in a flask containing 40 mL of 7% ammonium bicarbonate aqueous solution and lyophilized. The lyophilized powder was dissolved in water (2 mL) and then submitted to further purification by HPLC employing an LS-410 column (300 8 mm, 10 ím, TOSOH) with 0.5% aqueous acetic acid-acetonitrile
(10:1) as the mobile phase. The desired fraction (Ve 20-22 mL) was lyophilized to obtain a light yellow amorphous powder of 3 (5 mg):IR 3300 (OH, NH), 1760 (â-lactam CO), 1620 (CONH), 1530 (NH), and 990 (NO) cm-1; 1H-NMR (Me2SO-d6, Me4Si) ä 3.60 and 3.74 (ABq,2, J ) 17.6 Hz, SCH2), 4.86 (d, 1, J ) 2.4 Hz, 6-H), 4.90 (dd, 1, J )2.4 and 7.8 Hz, 7-H), 5.19 (d, 1, J ) 11.2 Hz, vinyl), 5.43 (d, 1, J )
17.3 Hz, vinyl), 6.70 (s, 1, Ar), 6.73 (dd, 1, J ) 11.2 and 17.3 Hz, vinyl),7.13 (br s, 2, NH2), 9.48 (d, 1, J ) 7.8 Hz, CONH), and 11.40 ppm (brs, 1, NOH); UV ìmax 230 ( 15 600) and 288 nm (21 900); MS (SI-MS) m/z 396 ([M + H]+); [R]20D (2% aqueous NaHCO3) +47.7°.

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