With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.108-55-4,Dihydro-2H-pyran-2,6(3H)-dione,as a common compound, the synthetic route is as follows.
EXAMPLE 2; Synthesis of Mono-carbonyl butanoic acid 3; To a solution of 2.01 g (5.46 mmol) of curcumin, 1 12 mg (0.92 mmol) of DMAP, and 0.685 g (6 mmol) glutaric anhydride (95%) in 100 ml THF was added 1.33 ml (9.55 mmol) Et3N. The reaction was stirred at reflux under argon overnight. Purified on column chromatography, eluting with CH2Cl2-CH2Cl2)MeOH, 95:5. Yield 84%. NMR 1H (CDCl3), delta (ppm): compound (3),1.97-2.14 (m, 2H); 2.43-2.79 (m, 4H); 3.87-3.95 (d, 6H); 5.83 (s, 2H); 6.45-6.59 (t, 2H); 6.91-7.18 (m, 6H); 7.57-7.65 (d, 2H). 13C NMR (CDCl3), delta (ppm): 19.98; 32.76; 55.82; 101.61 ; 109.86; 1 1 1.36; 1 15.04; 120.95; 121.54; 123.05; 124.16; 127.35; 133.89; 139.38; 139.99; 141.06; 147.03; 148.22; 151.23; 170.98; 177.374; 181.73; 184.65. MS (ESI) calcd. for C26H26O9: 482.48; found: 483.2 [M+H]+. See Robert E. Gawley; Mykhaylo Dukh; Claudia M. Cardona; Stephan H. Jannach; Denise Greathouse. Org. Lett.., Vol. 7, No. 14, 2005.2953-2956.
As the paragraph descriping shows that 108-55-4 is playing an increasingly important role.
Reference£º
Patent; RESEARCH FOUNDATION OF THE CITY UNIVERSITY OF NEW YORK; WO2008/45534; (2008); A2;,
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