87691-88-1,With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.87691-88-1,3-Piperazinobenzisothiazole hydrochloride,as a common compound, the synthetic route is as follows.
A round bottomed flask was charged with 5 g (22.8 mmol) of 3- (1- piperazinyl)-1, 2-benzisothiazole and 20 mL dimethylformamide dimethylacetal. The solution was heated to 90 C for 20 h and then concentrated in vacuo. The resulting yellow solid was treated with 3.76 g (2, 6-dimethyl-3-nitropyridine in 22 mL DMF and heated to 100 C for 48 h. The reaction was then cooled and concentrated in vacuo. This crude reaction product was dissolved in 90 mL dichloroethane and 1.9 mL (33 MMOL) HOAc, cooled to 0 C, and treated with 9.4 g (44 MMOL) NaBH (OAC) 3. The reaction was allowed to warm to rt overnight and then stirred for 90 h. The reaction was quenched with 200 mL K2CO3 and 100 mL CH2C12. The organic extracts were dried over MGS04, filtered, and concentrated in vacuo to give 15.5 g of a red liquid. This red liquid was crudely purified by filtration chromatography to give 5.3 g of a crude mixture of the desired nitro compounds as an approximate 1: 1 mixture. This crude mixture was hydrogenated (50 psi) for-65 h in 100 mL THF : TRIETHYLAMINE (19: 1) using RaNi catalyst. The reaction was filtered and concentrated to give 5 g of crude material which was purified BY SI02 chromatography using a gradient of EtOAc to 10% MeOH/EtOAc. This purification gave 0.30 G of isomer A and 0.46 g of isomer B, both as orange oils. Additionally, 1.1 g of a fraction containing both isomers was isolated. Isomer A : MS (APCI) : 354 [M+H] +. Isomer B: MS (APCI) : 354 [M+H]+.
The synthetic route of 87691-88-1 has been constantly updated, and we look forward to future research findings.
Reference£º
Patent; WARNER-LAMBERT COMPANY LLC; WO2004/41793; (2004); A1;,
Isothiazole – Wikipedia
Isothiazole – ScienceDirect.com