| Clerodendranthus spicatus (Thunb.) C.Y.Wu belongs to Clerodendranthus species in Lamiaceae family. There are about five species of Clerodendranthus in the world, and mainly distributed in tropical regions such as Indonesia, Malaysia, Myanmar, the Philippines and so on. The whole plant is used as medicine with the effect of heat-cleaning,dampness-eliminating and removing urinary calculus, which has the magical effect for the treatment of nephritis, chronic nephritis, cystitis, urinary tract stones, kidney stones,gallstones, rheumatoid arthritis and other diseases. The widely use of Clerodendranthus as medicine led to the increasing market demand, however, because of climate change and the destruction of wild Clerodendranthus, this resource was close to be endangered,which is difficult to meet the large market demand. Luckily,the generalization of cultivated C.spicatus in Hainan recently years fill the market demand to some extent. Previous studies on C. spicatus were mainly focused on their pharmacological activity of crude extracts,however,the specific active ingredient is still not clear. In order to study the chemical composition of this genus and to find out bioactive compounds, the chemical investigations on ethyl acetate partition from ethanol extract of cultivated C. spicatus was carried out,with the further purpose to exploit the cultivated C. spicatus in Hainan.Twenty-six compounds were isolated from the cultivated C.spicatus in Hainan by various chromatographies. Their structures were elucidated by physical and chemical properties, as well as spectral data (NMR, MS, IR, UV), which lead to:6-epi-1-oxo-15-hydroxyverbesindiol (1), vomifoliol (2), (-)-syringaresinol (3), hedyolisol(4), (+)-pinoresinol (5), N-trans-feruloyltyramine (6), 3,3’,5-trihydroxy-7,4’-dimethoxyflavanone (7),5,4’-trihydroxy-7,3’-dimethoxyflavanone (8),5-hydroxy-3’,4’,7-trimethoxyflavanone (9),5,3’-trihydroxy-7,4’-dimethoxyflavanone (10),5,3’-trihydroxy-6,7,4’-dimethoxyflavanone (11),5-hydroxy-6,7, 3’,4’-trimethoxyflavanone (12), 3’-hydroxy-5,7,8,4’-tetramethoxyflavone (13), 3,4-dihydroxyphenylethyl alcoho (14), 6-hydroxy-5,7,4.’-trimethoxyflavone (15), sinesetin (16), 5-hydroxy-6,7,3’,4’-tetramethoxyflavone (17),5,6,7,4’-tetramethoxyflavone (18),3,4-dihydroxyphenylethanol(19), 3,4-a-trihydroxy-mephenylpropionate (20), protocatechuic aldehyde (21), caffeic acid(22),methyl caffeate (23),ethyl caffeate (24),methyl rosmarinate (25),and ursolic acid(26). Compound 1 is a new sesquiterpene,compound 2 is a subtractorpene,compounds 3-5 are lignans, compound 6 is an amide alkaloid, compounds 7-18 are flavonoids (including dihydroflavones: 7-11),compounds 19 and 20 are phenols,compounds 21-25 are phenylpropanoids, and compound 26 is a triterpene. Compounds 5-11, 18, 19, 21 were isolated from C. spicatus for the first time.Compounds 2-4, 6, 8, 10, 11,13,16-25 were submitted to the acetylcholinesterase inhibitory activity assay using the Ellman method for the first time. The results showed that compounds 13,16,18,19,22,24,and 25 presented inhibitory activity against acetylcholinesterase. The determination of a-glucosidase inhibitory activity was carried out using the PNPG method for the above compounds. The results showed that compounds 6,22, and 23 presented strong inhibitory activity against α-glucosidase, while compounds 19,21, and 24 showed weak inhibitory activity.The cytotoxic activity of BEL-7402 and SGC-7901 tumor cell lines were determined by MTT method for compounds 3, 4, 6, 8, 10, 11,13, 18, and 20-25. The results showed that only compounds 23 and 24 presented weak inhibitory activities against both cell lines. |
