ABSTRACT
The synthesis of a series of bicyclo[4.2.2]octenones and bicyclo[3.2.2]heptenones by 1,3- or 1,2-migration reaction from 2-vinylbicyclo[2.2.2]octenols is reported. These ring-expansion reactions were accomplished under basic or neutral conditions. Whether 1,3- or 1,2-migration takes place depends on endo- or exocyclic olefin displacement in the substrates.
Subject(s)
Bridged Bicyclo Compounds/chemical synthesis , Carbon/chemistry , Furans/chemistry , Octanes/chemistry , Vinyl Compounds/chemical synthesis , Alkenes/chemistry , Anions/chemistry , Bridged Bicyclo Compounds/chemistry , Models, Molecular , Molecular Structure , Vinyl Compounds/chemistryABSTRACT
OBJECTIVE: To provide the foundation for reasonable utilization by analysing the essential oils from Serissa serissoides in different seasons. METHOD: Essential oils were obtained by steam distillation. The chemical components were separated and identified by gas chromatography-mass spectrometer (GC-MS). The relative content of each component was determined by area normalization. RESULT: Forty-three peaks were identified from autumn material, representing 78.91% of the total oil. Main constituents of the essential oil from the autumn material were found to be 1b,5,5,6a-tetramethyl-octahydro-1-oxa-cyclopropa [a] inden-6-one (7.32%); methyl linolenate (4.14%); cubenol (5.97%); 2-methoxy-4-vinylphenol (10.87%); delta-9(10)-tetrahydrocostunolide-1-keto (35.51%). Seventy-two peaks were identified from spring material, representing 79.88% of the total oil. Main constituents of the essential oil from the spring material were found to be caryophyllene (3.315%); ethylbenzene (3.523%); 3-hexen-1-ol (4.537%); 2-methoxy-4-vinylphenol (6.513%); 5-propionyl-2-chlorobenzeneacetic acid, methyl ester (8.541%), germacrene D (12.311%). CONCLUSION: The same compounds in both materials are as follows: 2,2-dimethyl-6-methylene-cyclohexanepropanol; 2-methoxy-4-vinylphenol; 3,7-dimethyl-1,6-octadien-3-ol; cubenol; docosane and eicosane. It seems that they are the diagnostic components in these medicinal materials. Essential substances are different in quantity and quality in different seasons.
