With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.3663-80-7,2,3-Dihydrobenzo[b][1,4]dioxine-2-carboxylic acid,as a common compound, the synthetic route is as follows.,3663-80-7
EXAMPLE 26 Preparation of (-)-N-[[3-[4-[4-[(2,3-Dihydro-1,4-benzodioxin-2-yl)carbonyl]-1-piperazinyl]-3,5-difluorophenyl]-4,5-dihydro-5-isoxazolyl]methyl]acetamide. To a flame dried flask containing (-)-N-[[4,5-dihydro-3-[3,5-difluoro-4-(1-piperazinyl)phenyl]-5-isoxazolyl]methyl]acetamide (see Example 25) (175 mg), 1,4-benzodioxan-2-carboxylic acid (112 mg, 0.0.62 mmol), DMAP (7 mg) in pyridine (~5 mL) is added EDC (119 mg) at ambient temperature and stirred for 3 days. The reaction is diluted with CH2Cl2 (25 mL) and washed with H2O (2 X 50 mL) and saline (50 mL). The organic phase is dried over sodium sulfate, filtered and concentrated in vacuo and chromatographed on silica gel (230-400 mesh, 100 mL), eluding with chloroform/methanol. The appropriate fractions are combined and concentrated to give the title compound, mp 158-159 ¡ãC, [alpha]25D -41 (CHCl3).
As the paragraph descriping shows that 3663-80-7 is playing an increasingly important role.
Reference£º
Patent; PHARMACIA & UPJOHN COMPANY; EP1054874; (2002); B1;,
Benzodioxan
1,4-Benzodioxane | C8H8O2 – PubChem