In the chemical reaction process,reaction time,type of solvent,can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product.An updated downstream synthesis route of 272437-84-0,3-Oxo-3,4-dihydro-2H-1,4-benzothiazine-6-carboxylic acid, as follows.272437-84-0
Preparation of 4-[(3-oxo-3,4-dihydro-2H-benzo[l ,41thiazine-6-carbonyl)-aminol-piperidine- 1-carboxylic acid tert-butyl ester:3-Oxo-3,4-dihydro-2H-benzo[l,4]thiazine-6-carboxylic acid (556 mg, 2.45 mmol, 1.0 eq) is added at room temperature to a stirred solution of 4-amino-piperidine- 1-carboxylic acid tert- butyl ester (500 mg, 2.45 mmol, 1.0 eq) in N,N-dimethylformamide (20 mL), followed by 1- hydroxybenzotriazole (421 mg, 2.69 mmol, 1.1 eq), N-(3-dimethylaminopropyl)-N’- ethylcarbodiimide hydrochloride (550 mg, 2.81 mmol, 1.15 eq) and N,N- diisopropylethylamine (962 L, 5.50 mmol, 2.25 eq). After 15 hours stirring at room temperature, solvent is evaporated and the residue is extracted with dichloromethane (3 x 30 – – mL) and water (30 mL). The combined organic layers are dried over sodium sulfate, filtered and concentrated to give a crude product that is purified by column chromatography (silica gel, eluent: cyclohexane:ethyl acetate :methanol, 1 :3:0 to 0/9/1, v/v/v) to afford 4-[(3-oxo-3,4- dihydro-2H-benzo [ 1 ,4]thiazine-6-carbonyl)-amino ] -piperidine- 1 -carboxylic acid tert-butyl ester as a light yellow solid (621 mg, 62% yield).1H-NMR (400 MHz, DMSO- 6) delta ppm: 10.66 (s, 1H), 8.27 (d, J = 7.8 Hz, 1H), 7.42 (m, 3H), 3.96 (m, 3H), 3.51 (s, 2H), 2.90 (m, 2H), 1.76 (m, 2H), 1.40 (m, 11H).MS m/z (+ESI): 392.3 [M+H]+, 414.3 [M+Na]+.
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 272437-84-0, and friends who are interested can also refer to it.
Reference£º
Patent; BASILEA PHARMACEUTICA AG; GAUCHER, Berangere; DANEL, Franck Hubert; XIE, Tong; XU, Lin; WO2012/171860; (2012); A1;,
Thiazine – an overview | ScienceDirect Topics
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