3,4-dihydro-2H-chromen-2-ol

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 12-Acetoxycalanolide A (2), [α]D =+20°, gave a parent ion by HREIMS at m/z 412.1825 daltons corresponding to a molecular formula of C24H28O6. Significant fragment ions were observed for M+ --CH3 (m/z 397, 41%), M+ -AcOH (m/z 352, 30%) and M+ -AcOH--CH3 (m/z 337, 100%). The presence of an acetate group was suggested by a sharp 3H singlet in the 1H NMR spectrum at δ 2.10 and 13C NMR resonances at δ 21.2 (3H) and 170.7. The remaining 1H and 13C NMR signals for compound 2 were very similar to those recorded for calanolide A (1), except that the H12 resonance in compound 2 was shifted downfield to δ 5.97. This suggested that compound 2 was the 12-acetoxy derivative of calanolide A (1). The J10-11 (6.5 Hz) and J11-12 (6.0 Hz) couplings in compound 2 supported a pseudoaxial orientation of the chromanol ring protons. The slightly diminished chromanol proton couplings in compound 2 conceivably resulted from a slight twisting of the flexible chromanol ring. Further evidence for the proposed substituent configuration was provided by difference nOe enhancements of 2% measured between H10 and H12.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 12-Acetoxycalanolide A (2), [α]D =+20°, gave a parent ion by HREIMS at m/z 412.1825 daltons corresponding to a molecular formula of C24H28O6. Significant fragment ions were observed for M+ --CH3 (m/z 397, 41%) M+ --AcOH (m/z 352 30%) and M+ --AcOH--CH3 (m/z 337, 100%). The presence of an acetate group was suggested by a sharp 3H singlet in the 1H NMR spectrum at δ 2.10 and 13C NMR resonances at δ 21.2 (3H) and 170.7. The remaining 1H and 13C NMR signals for compound 2 were very similar to those recorded for calanolide A (1), except that the H12 resonance in compound 2 was shifted downfield to δ 5.97. This suggested that compound Z was the 12-acetoxy derivative of calanolide A (1). The J10-11 (6.5 Hz) and J11-12 (6.0 Hz) couplings in compound 2 supported a pseudoaxial orientation of the chromanol ring protons. The slightly diminished chromanol proton couplings in compound 2 conceivably resulted from a slight twisting of the flexible chromanol ring. Further evidence for the proposed substituent configuration was provided by difference nOe enhancements of 2% measured between H10 and H12.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution was prepared by dissolving 10 g (0.0318 mole) of 5-n-octyloxy-1-hydroxy-2-acetonaphthone, 2.77 g (0.0477 mole) of acetone and 1.13 g (0.0159 mole) of pyrrolidine 100 ml of toluene, and the solution was boiled for 10 hours and water was separated. After termination of the reaction, toluene was removed under reduced pressure, and the remaining chromanone compound was dissolved in 100 ml of methanol and sodium boron hydride was gradually added to the solution to form a chromanol compound. Then, 6.0 g of the chromanol compound was heated at 150° C. to 160° C. together with 4.0 g of anhydrous copper sulfate in a carbon dioxide current for 10 minutes. The obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 3.8 g of a chromene compound represented by the following formula: ##STR255## The obtained brown viscous liquid was purified by the chromatography on silica gel

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution was prepared by dissolving 10 g (0.0318 mole) of 5-n-octyloxy-1-hydroxy-2-acetonaphthone, 2.77 g (0.0477 mole) of acetone and 1.13 g (0.0159 mole) of pyrrolidine 100 ml of toluene, and the solution was boiled for 10 hours and water was separated. After termination of the reaction, toluene was removed under reduced pressure, and the remaining chromanone compound was dissolved in 100 ml of methanol and sodium boron hydride was gradually added to the solution to form a chromanol compound. Then, 6.0 g of the chromanol compound was heated at 150° C. to 160° C. together with 4.0 g of anhydrous copper sulfate in a carbon dioxide current for 10 minutes. The obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 3.8 g of a chromene compound represented by the following formula: ##STR255## The obtained brown viscous liquid was purified by the chromatography on silica gel

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In the same manner as described in Example 32, the formed chromanone compound was converted to a chromanol compound, and the dehydration reaction, separation and purification were carried out to obtain 6.58 g of a chromene compound represented by the following formula: ##STR167## the dehydration reaction, separation and purification

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In 50 cc of anhydrous ether was dissolved 3.06 g (0.01 mole) of the chromanone compound obtained in Example 32, represented by the following formula: ##STR163## and the solution was cooled to 0° C. and Grignard reagent CH3MgI (0.012 mole) newly prepared in 50 cc of anhydrous ether was dropped into the solution over a period of about 1 hour. After termination of the dropwise addition, the mixture was stirred at room temperature for 2 hours and quietly poured into cold water to extract the product with ether. The ether extract was dried on magnesium sulfate to form a chromanol compound from the chromanone compound. Then, the chromanol compound was heated at 200° C. together with anhydrous copper sulfate in a carbon dioxide current for about 10 minutes. The obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 2.47 g of a chromene compound represented by the following formula: ##STR164## The obtained brown viscous liquid was purified by the chromatography on silica gel

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In 50 cc of anhydrous ether was dissolved 3.06 g (0.01 mole) of the chromanone compound obtained in Example 32, represented by the following formula: ##STR163## and the solution was cooled to 0° C. and Grignard reagent CH3MgI (0.012 mole) newly prepared in 50 cc of anhydrous ether was dropped into the solution over a period of about 1 hour. After termination of the dropwise addition, the mixture was stirred at room temperature for 2 hours and quietly poured into cold water to extract the product with ether. The ether extract was dried on magnesium sulfate to form a chromanol compound from the chromanone compound. Then, the chromanol compound was heated at 200° C. together with anhydrous copper sulfate in a carbon dioxide current for about 10 minutes. The obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 2.47 g of a chromene compound represented by the following formula: ##STR164## The obtained brown viscous liquid was purified by the chromatography on silica gel

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution was prepared by dissolving 10 g (0.054 mole) of 1-acetyl-2-naphthol, 8.29 g (0.06 mole) of bicyclo[3,3,1]nonan-9-one and 8.7 g (0.10 mole) of morpholine in 300 cc of toluene, and the solution was boiled for 5 hours and water was separated. After termination of the reaction, toluene was removed under reduced pressure and the remaining chromanone compound was recrystallized from acetone. Then, the chromanone compound was dissolved in 200 cc of methanol and lithium aluminum hydride was added to the solution to form a chromanol compound. Then, 6.49 g of this chromanol compound was heated at 170° C. to 180° C. together with anhydrous copper sulfate in a carbon dioxide current for 10 minutes, and the obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 5.8 g of a chromene compound represented by the following formula: ##STR162## the obtained brown viscous liquid was purified by the chromatography on silica gel

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution was prepared by dissolving 10 g (0.054 mole) of 1-acetyl-2-naphthol, 8.29 g (0.06 mole) of bicyclo[3,3,1]nonan-9-one and 8.7 g (0.10 mole) of morpholine in 300 cc of toluene, and the solution was boiled for 5 hours and water was separated. After termination of the reaction, toluene was removed under reduced pressure and the remaining chromanone compound was recrystallized from acetone. Then, the chromanone compound was dissolved in 200 cc of methanol and lithium aluminum hydride was added to the solution to form a chromanol compound. Then, 6.49 g of this chromanol compound was heated at 170° C. to 180° C. together with anhydrous copper sulfate in a carbon dioxide current for 10 minutes, and the obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 5.8 g of a chromene compound represented by the following formula: ##STR162## A solution was prepared water was separated After termination of the reaction, toluene was removed under reduced pressure the remaining chromanone compound was recrystallized from acetone Then, the chromanone compound was dissolved in 200 cc of methanol lithium aluminum hydride was added to the solution

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution was prepared by dissolving 10 g (0.054 mole) of 1-acetyl-2-naphthol, 8.29 g (0.06 mole) of bicyclo[3,3,1]nonan-9-one and 8.7 g (0.10 mole) of morpholine in 300 cc of toluene, and the solution was boiled for 5 hours and water was separated. After termination of the reaction, toluene was removed under reduced pressure and the remaining chromanone compound was recrystallized from acetone. Then, the chromanone compound was dissolved in 200 cc of methanol and lithium aluminum hydride was added to the solution to form a chromanol compound. Then, 6.49 g of this chromanol compound was heated at 170° C. to 180° C. together with anhydrous copper sulfate in a carbon dioxide current for 10 minutes, and the obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 5.8 g of a chromene compound represented by the following formula: ##STR162## A solution was prepared water was separated After termination of the reaction, toluene was removed under reduced pressure the remaining chromanone compound was recrystallized from acetone Then, the chromanone compound was dissolved in 200 cc of methanol lithium aluminum hydride was added to the solution