Studies On The Chemical Constituents And Bioactivities Of Calophyllum Inophyllum Linn And Stephania Succifera Lo Et Y.Tsoong

Calophyllum inophyllum Linn. belongs to the genus Calophyllum of family Clusiaceae (or Guttiferae), which distributed in Yunnan, Guangxi, Hainan and Taiwan provinces of China. C. inophyllum is used in traditional Chinese folk medicine for the treatment of wounds, inflammations, rheumatisms and eye diseases etc.To search for new bioactive constituents, especially the antitumor bioactive components from C. inophyllum of Hainan, a systematic investigation on the chemical constituents of C. inophyllum was undertaken.Eighteen compounds were isolated from C. inophyllum by chromatographic methods. With the extensive spectroscopic technology including 1D NMR (¹H-NMR, ¹³C-NMR, DEPT), 2D NMR (¹H-¹H COSY, HMQC, HMBC, ROESY), HRESI-MS, FAB-MS, UV, IR et.al, the compounds were unambiguously elucidated as: Caloxanthone Q (1), 6-hydroxy-2,3-dimethoxyxanthone (2), Caloxanthone T (3), Caloxanthone O (4), 2-deprenyl-rheediaxanthone B (5), Jacareubin (6), 6-Deoxyjacareubin (7), 1,3,7-trihydroxyxanthone (8), 1,3,7-trihydroxy-8-methoxyxan -thone (9), 7-hydroxy-1,3-dimethoxyxanthone (10), 2-hydroxy-1-methoxyxanthone (11), 1,3,6-trihydroxy-5,7-dimethoxyxanthone (12), 2-hydroxy-1,8-dimethoxyxantho- ne (13), 1,3,5-trihydroxy-2-methoxyxanthone (14), 4-hydroxyxanthone (15), 1,3,5-tri -hydroxyxanthone (16), pseudo taraxasterol (17), Daucosterol (18). Among them, compound 1 was new, compound 2 was a new natural product, compounds 8 13 and 17 were isolated from this plant for the first time, compounds 8 10 and compound 17 were isolated from the plants of the genus Calophyllum for the first time. The cytotoxic activities of the 16 xanthones were tested by MTT assay.Compounds 4 and 14 showed cytotoxic activities against human gastric carcinoma (SGC-7901) cell lines, with IC₅₀ values of 53.9μg·mL^-1 and 5.0μg·mL^-1 either. The antimicrobial activities against Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus (MRSA) of the xanthones were measured using paper disco diffusion method. Among them, compounds 3 and 6 exhibited antimicrobial activities towards the two pathogenic bacteria in different degrees.Stephania succifera Lo et Y. Tsoong (Menispermaceae) is a species of the genus Stephania. Phytochemical studies on the plants of this genus indicated that the main chemical constituents were isoquinoline alkaloids, which show several pharmacological activities such as antitumor, antimalarial, antihypertensive, et.al. In view of the important medicinal value as a traditional folk medicine, the tuber of S. succifera was studied under bioassay guidance of antitumor and antimicrobial for the purpose of getting more bioactive compounds and providing scientific evidence for better exploiting this plant.Eight compounds were isolated from the ethanol extract of the tubers of S. succifera by chromatographic methods, and their structures were indentified by physicochemical properties and spectral data (UV, IR, MS, 1D and 2D NMR) as N-formyl-asimilobine-2-O-β-D-glucoside (1), Stephiferine A -2-O-β-D-glucoside (2), (–)-1-O-β-D-glucoside-8-oxotetrahy-dropalmatine (3), Stephiferine B -2-O-β-D-glu- coside (4), 1-N-monomethyl-carbamate-argentinine-3-O-β-D-glucoside (5), Dehydro- corydalmine (6), Palmatine (7), Crebanine N-oxide (8). Among them, compounds 1-5 were new glycoalkaloids.The cytotoxic activities of the 8 alkaloids were tested by MTT assay, and none of them exhibited cytotoxic activities against chronic myelogenous leukemia (K562), human gastric carcinoma (SGC-7901) and human hepatoma (SMMC-7721) cell lines.The antimicrobial activities of all the compounds were examined by the filter paper disc agar diffusion method, compound 2 showed inhibitory activity towards methicillin-resistant Staphylococcus aureus (MRSA), compound 3 exhibited inhibitory activity towards Staphylococcus aureus (MRSA) and compounds 5-8 exhibited antimicrobial activities towards the two pathogenic bacteria.