Studies On The Chemical Constituents Of Toona Ciliata Var. Pubescens

Toona ciliata var. pubescens. belongs to the family Meliaceae which is widely distributed in the tropical areas of Asia such as India, Malaysia, Indonisia, and southern China. The timber is red in colour, easy to work and very highly valued. It was used extensively for furniture, wood panelling and construction, and was considered as "Chinese mahogany".Previous investigations on Meliaceae revealed the presence of coumarin, terpenoids, and campesterol. However, no phytochemical investigations have been reported on this plant.In this study, we investigated the chemical constituents of Toona ciliata var. pubescens. which collected from Xiushui, Jiangxi province. Thirty-nine coumpounds were isolated and their structures were identified by extensive spectroscopic methods including 1D and 2D-NMR experiments or by comparing their spectral data with those published in the literatures. These compounds were identified as follows:TC-1: SiderinTC-2: 4, 6, 7-Trimethoxy-5-methylcoumarinTC-3: IsoscopoletinTC-4: ScopoletinTC-5: 6, 7-DimethoxycoumarinTC-6: 7-Hydroxy-6, 8-dimethoxycoumarinTC-7: Dehydrodiconiferyl alcoholTC-8: (?)-LariciresinolTC-9: Threo-2, 3-bis-(4-hydroxy-3-methoxypheyl)-3-methoxy-propanol*TC-10: (7S, 8S, 7′E)-4, 9-Dihydroxy-3, 7, 3′, 9′-tetramethoxy-8-4′- oxyneolignan -7′-ene *TC-11: (7R, 8S, 7′E)-4, 9-Dihydroxy-3, 7, 3′, 9′-tetramethoxy-8-4′- oxyneolignan -7′-ene*TC-12: (7S, 8S, 7′E)-5, 9-Dihydroxy-3, 7, 3′, 5′, 9′-pentamethoxy-8-4′- oxyneolignan -7′-eneTC-13: CycloeucalenolTC-14: 5α, 6β, 8α, 12α-Tetrahydroxy-28-norisotoonafolinTC-15: 8 (14), 15-Isopimaradiene -2, 3, 19-triolTC-16: 3S, 5R-Dihydroxy-6R, 7-megstigmadien-9-oneTC-17: (?)-LoliolideTC-18: (+)-CatechinTC-19: 3-Hydroxy-1-(4-hydroxy-3-methoxyphenyl)-propan-1-oneTC-20: 2, 3-Dihydroxy-1-(4-hydroxy-3-methoxyphenyl)-propan-1-one*TC-21: Threo-3, 7-dimethoxy-5-hydroxyphenylpropan-8, 9-diolTC-22: Threo-3, 7-dimethoxy-4-hydroxyphenylpropan-8, 9-diolTC-23: Dimethyl malateTC-24: Diisobutyl phthalateTC-25: Dibutyl phthalateTC-26: Syringic acidTC-27: SyringaldehydeTC-28: Vanillic acidTC-29: VanillinTC-30: 3, 4-Dimethoxy-benzoic acidTC-31: 2-(2-Hydroxyethyl)-4-methoxybenzoic acidTC-32: 1, 3, 5-Trimethoxy benzeneTC-33: IsovanillinTC-34: 3, 3′, 5, 5′-Tetra-tert-butyl-2, 2′-dihydroxybiphenylTC-35:β-sitosterolTC-36: DaucosterolTC-37: Palmitic monoglycerol esterTC-38: Tricosanoic acid TC-39: Hexadecanoic acidAll the compounds were isolated from this plant for the first time. TC-10, TC-11, TC-12, TC-21 and TC-22 were new compounds. Among them, TC-10, TC-11, and TC-12 were lignans, TC-21 is phenylpropanoid.Furthermore, we also investigated the anti-proliferative activities against four tumor cells lines of 18 compounds by MTT method (A549, Colo 205, QGY-7703 and LOVO). TC-32 showed moderate anti-proliferative activities against QGY-7703 and LOVO with IC50 values of 36.2 and 11.7μM, respectively.