3-亚甲基二氢呋喃-2,5-二酮

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: S-trans, trans-Farnesyl-L-cysteine (500 mg, 1.54 mmol) was dissolved in mixture of THF and a first portion of K2CO3 (3 mmol) and the resulting solution was cooled to 5° C. with vigorous stirring. To this stirred solution was added 3-methylenedihydro-2,5-furandione (302 mg, 3.07 mmol) portionwise while maintaining the pH at 9.0-10.0 with another portion of K2CO3 (3 mmol). The mixture was stirred at room temperature for 3 h. HPLC analysis showed completion of the reaction. The pH of the reaction mixture then adjusted to 2.0 by the addition of 2 N HCl solution. The acidic solution was extracted three times with 15 mL of ethyl acetate. The combined organic extract was washed with water, brine and dried over Na2SO4, the solvent was removed under reduced pressure to afford crude Compound F, which was further purified by preparative HPLC (552 mg, 82%) to yield Compound F. 1H-NMR (500 MHz, CDCl3): δ 1.59 (s, 6H), 1.67 (s, 3H), 1.68 (s, 3H), 2.05 (m, 8H), 2.88 (dd, J=6.5, 14.0, 1H), 2.95 (dd, J=6.5, 14.0, 1H), 3.17-3.15 (m, 2H), 3.36 (d, J=14 Hz, 1H), 4.77 (dd, J=6, 12.5 Hz, 1H), 5.09 (bt, 2H), 5.22 (t, J=7.5 Hz, 1H), 5.93 (s, 1H), 6.46 (s, 1H). 13C-NMR (125 MHz, CDCl3): δ 16.0, 16.2, 17.7, 25.7, 26.7, 29.9, 32.8, 39.6, 39.7, 40.2, 52.0, 119.4, 123.7, 131.3, 132.0, 135.4, 140.3, 170.3, 171.5, 176.0; ES-MS: mass calcd for Chemical Formula: C23H35NO5S 437.6. Found (M+Na) m/z 446. completion of the reaction The acidic solution was extracted three times with 15 mL of ethyl acetate The combined organic extract was washed with water, brine dried over Na2SO4 the solvent was removed under reduced pressure to afford crude Compound F, which was further purified by preparative HPLC (552 mg, 82%)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A suspension of 8.0 g of anhydrous aluminum chloride and 3.59 of itaconic acid anhydride in dried tetrachloroethane was stirred for one hour at room temperature. To this solution, 4.39 g of 2-ethylbenzofuran dissolved in 10 ml of tetrachloroethane was added dropwise under cooling by ice-water. And then stirring was continued for 3 hrs. in ice-water and for 12 hrs. at room temperature. The reaction mixture was poured into the mixture of 80 g of ice and 20 ml of conc. HCl, then extracted with ethylacetate (50 ml). After washed with water, the solvent layer was made alkaline with 10% NaCO3 solution. The water layer was acidified with 10% HCl again and then extracted with ethylacetate. The brown viscous residue obtained after washing, drying and removal of ethyl acetate layer, was extracted with ligroin. After standing overnight, the needle-like crystals were obtained. was added dropwise And then stirring was continued for 3 hrs at room temperature extracted with ethylacetate (50 ml) After washed with water extracted with ethylacetate The brown viscous residue obtained after washing drying removal of ethyl acetate layer was extracted with ligroin After standing overnight the needle-like crystals were obtained

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir: