With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.107869-45-4,(3aR,6S)-8,8-Dimethyl-4,5,6,7-tetrahydro-3H-3a,6-methanobenzo[c]isothiazole 2,2-dioxide,as a common compound, the synthetic route is as follows.
EXAMPLE 1; (1R)-(+)-2,10-Camphor Sultam (Scheme 3, 3-1); To a solution of (-) camphor sulfonic acid (1.45 kg, 6.25 mol) in chloroform (7 L) under reflux condition is added thionyl chloride (0.896 kg, 7.5 mol) over a period of 1 h. The reaction mixture is refluxed for 16 h and then cooled to 4 C. using an ice bath. This cooled reaction mixture is added slowly to conc. NH4OH (15 L) while maintaining the temperature below 15 C. during the addition. After addition, the mixture is stirred for 4 h at room temperature. The organic layer is separated and the aqueous layer is extracted with chloroform (2¡Á2 L). The combined organic extracts are washed with brine (4 L) and dried over MgSO4. After filtration, the filtrate is concentrated under vacuum and dried to give 1.2 kg (83%) of camphor sulfonamide. In one experiment at 145 g scale of camphor sulfonic acid, the use of dichloromethane instead of chloroform for the reaction and extraction gives comparable yields. To a suspension of the camphor sulfonamide (1.2 kg, 5.2 mol) in toluene (15 L) is added Amberlyst H+ resin (150 g), and the mixture is heated at reflux for 4 h with the water formed removed azeotropically using a Dean-Stark water separator. The reaction mixture is filtered hot to remove the resin. The filtrate on cooling gave a white solid which is collected by filtration to give 1.02 kg (92%) of the desired imine. To the above imine (100 g, 0.47 mol) in ethanol (0.75 L) is added Raney Nickel (100 g) and the mixture is hydrogenated at 40 psi for 2 h. The catalyst is removed by filtration and the filtrate concentrated under vacuum to give the product 3-1 as a white solid
107869-45-4 (3aR,6S)-8,8-Dimethyl-4,5,6,7-tetrahydro-3H-3a,6-methanobenzo[c]isothiazole 2,2-dioxide 719800, aisothiazole compound, is more and more widely used in various.
Reference£º
Patent; BioCryst Pharmaceuticals, Inc.; US2006/128789; (2006); A1;,
Isothiazole – Wikipedia
Isothiazole – ScienceDirect.com