We reported a facile synthesis of (-)-isochrysanthenone(2) from (-)-α-pinene in a high yield. When (-)-α-pinene reacted with O 2 in the presence of Co[4-Me(C 5H 4N) 2]Br 2 used as a catalyst, the crude product of (-...We reported a facile synthesis of (-)-isochrysanthenone(2) from (-)-α-pinene in a high yield. When (-)-α-pinene reacted with O 2 in the presence of Co[4-Me(C 5H 4N) 2]Br 2 used as a catalyst, the crude product of (-)-verbenone(1) was formed, and the crude product 1 was directly irradiated with ultraviolet light and converted into the (-)-isochrysanthenone(2). The structure of compound 2 was converted to a cyclic ester(4) by Baeyer-Villiger oxidation, the compound 4 was hydrolyzed to form a crystal 2,2,4-trimethyl-5-oxy-3-cyclohexenyl carboxylic acid 5. Compound 5 was confirmed by IR, 1H NMR and X-ray crystal analysis. In summary, we found that under the condition of photochemical rearrangement of (-)-verbenone and (+)-verbenone, different compounds were obtained, they are not enantiomers.展开更多
Essential oils chemical composition of,4rtemisia sieberi leaves/stems and flowers/fruits （F/F） growing wild in Kashan, central Iran, have been analyzed using GC-MS technique. This study was conducted in order to ide...Essential oils chemical composition of,4rtemisia sieberi leaves/stems and flowers/fruits （F/F） growing wild in Kashan, central Iran, have been analyzed using GC-MS technique. This study was conducted in order to identify and compare essential oil compounds in different aerial parts of Artemisia sieberi. Plants sampled at random in full flowering stage in a CR （completely randomized） design with three replications. Analysis on leaves/stems revealed 55 identified compounds, representing 97.66% of the oil with a-pinene being the main component （34.33%）; other significant components in the leaves/stems include： α-amorphene, β-pinene, δ-cadinene, α-cadinene, methyl cyclopentan. For flowers/fruits （F/F） 29 compounds were identified, representing 96.96% of the oil with the main component being α-amorphene （15.86%） and α-pinene （12.34%） being the second main component. A number of other significant components found in fiowers/fruits were α-campholene aldehyde, isopinocarveol, β-caryophylene, calarene, δ-cadinene. Several compounds （some with significant compositions） were found in this variety ofA. sieberi which are not reported in the previous literature.展开更多
文摘We reported a facile synthesis of (-)-isochrysanthenone(2) from (-)-α-pinene in a high yield. When (-)-α-pinene reacted with O 2 in the presence of Co[4-Me(C 5H 4N) 2]Br 2 used as a catalyst, the crude product of (-)-verbenone(1) was formed, and the crude product 1 was directly irradiated with ultraviolet light and converted into the (-)-isochrysanthenone(2). The structure of compound 2 was converted to a cyclic ester(4) by Baeyer-Villiger oxidation, the compound 4 was hydrolyzed to form a crystal 2,2,4-trimethyl-5-oxy-3-cyclohexenyl carboxylic acid 5. Compound 5 was confirmed by IR, 1H NMR and X-ray crystal analysis. In summary, we found that under the condition of photochemical rearrangement of (-)-verbenone and (+)-verbenone, different compounds were obtained, they are not enantiomers.
文摘Essential oils chemical composition of,4rtemisia sieberi leaves/stems and flowers/fruits （F/F） growing wild in Kashan, central Iran, have been analyzed using GC-MS technique. This study was conducted in order to identify and compare essential oil compounds in different aerial parts of Artemisia sieberi. Plants sampled at random in full flowering stage in a CR （completely randomized） design with three replications. Analysis on leaves/stems revealed 55 identified compounds, representing 97.66% of the oil with a-pinene being the main component （34.33%）; other significant components in the leaves/stems include： α-amorphene, β-pinene, δ-cadinene, α-cadinene, methyl cyclopentan. For flowers/fruits （F/F） 29 compounds were identified, representing 96.96% of the oil with the main component being α-amorphene （15.86%） and α-pinene （12.34%） being the second main component. A number of other significant components found in fiowers/fruits were α-campholene aldehyde, isopinocarveol, β-caryophylene, calarene, δ-cadinene. Several compounds （some with significant compositions） were found in this variety ofA. sieberi which are not reported in the previous literature.
