Studies On The Chemical Constituents Isodon Japonica

Background The genus Isodon is a perennial shrub or half shrub of Labiatae, Ninty species and twenty-five varieties of these species can be found in most every region of China, except QingHai province and Inner Mongolia. At present, more than80species of the genus Isodon have been researched and over500diterpenoids have been isolated from this genus. However, Isodon japonica which is from Longkong Mountain in Shanxi Province has not been reported.Objective (1) To study the chemical constituents of the leaves of Isodon japonica (Burm f.) Hara which were picked in Lingkong Mountain Shanxi province.(2) To study the chemical constituents of the whole plant of Isodon japonica (Burm f.) Hara which were picked in Tongbai County Henan province.Methods (1) The air-dried leaves of Isodon japonica which were picked in Lingkong Montain were powdered and extracted three times with Me2CO/HaO (7:3v/v) at room temperature for6days and filtered. The filtrate was concentrated and partitioned with AcOEt. The AcOEt layer was evaporated in under reduced pressure to obtain residue. The chemical constituents were separated by repeated silica gel column chromatography, Sephadex chromatography, PTLC and recrystallization. The structures were determined by spectral analyses (IR, UV,1H-NMR,13C-NMR, HMQC, HMBC,1H-1H NOESY, DEPT, EI-MS, HRESI-MS) and directly comparison with the standard sample.(2) The whole plant of Isodon japonica which were picked in Tongbai Conuty were extracted with Me2CO/H2O (7:3v/v) at room temperature. The chemical constituents were separated by silica gel column chromatography repeated and the structures were determined by spectral analyses.Results (1) Twenty nine compounds were obtained and identified from the extract of Isodon japonica picked in Lingkong Montain. There are two new compounds were isolated and identified as15a,20-dihydroxy-6,7-seco-ent-kaur-16-en-1,7α (6,11a) -diolide(1*)å'Œ6β-butanoxy-3β-hydroxy-6,7-seco-6,20epoxy-1α,7-olide-ent-kaur-16-en-15-one(2*). Among the remaining twenty seven compounds, they were all known diterpenoids including two glycoside.(2) Fithteen compounds were obtained from the whole plant of Isodon japonica picked in Tongbai County and twelve compounds were identified.Conclusion (1) From Isodon japonica (Burm f.) Hara picked in Lingkong Montain, two new compounds were isolated and identified. Six compounds were isolated from Isodon japonica (Burm f.) Hara for the first time..(2) From Isodon japonica picked in Tongbai County, twelve compounds were isolated and identified, one compound was isolated for the first time.