Structurally diverse diterpenoids from Trigonostemon howii.

Phytochemical investigation on the stems and leaves of Trigonostemon howii resulted in the isolation of a new abietane diterpenoid, trigohowimine A (1), along with seven known structurally diverse diterpenoids (2-8). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparison with data reported in the literature. New compound 1 was evaluated for its cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480. Compound 1 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 0.82 to 8.53 µM.

Furanocoumarins with potential antiproliferative activities from Clausena lenis.

A phytochemical investigation on the stems and leaves of Clausena lenis led to the isolation of a new furanocoumarin, clauselenisin A (1), together with five known analogues (2-6). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All known compounds (2-6) were isolated from C. lenis for the first time. All isolated compounds were evaluated for their their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1-6 showed significant antiproliferative effects with IC50 values ranging from 0.36 to 16.48 µM.

Carbazole alkaloids from Clausena emarginata with their potential antiproliferative activities.

A phytochemical investigation on the stems and leaves of Clausena emarginata led to the isolation of a previously undescribed carbazole alkaloid, clausemargine A (1), together with 11 known analogues (2-12). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All known compounds (2-12) were isolated from C. emarginata for the first time. All isolated compounds were evaluated for their their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1-12 showed significant antiproliferative effects with IC50 values ranging from 0.28 to 15.18 µM.

Novel γ-lactone derivatives from Trigonostemon heterophyllus with their potential antiproliferative activities.

Two novel γ-lactone derivatives, trigoheterophines A (1) and B (2), together with four known furan derivatives (3-6), were isolated from the stems and leaves of Trigonostemon heterophyllus. The structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparing with the data reported in literature. Among them, trigoheterophines A (1) and B (2) represent an unusual type of γ-lactone derivatives, possessing 21 carbon atoms on the carbon skeleton, and known compouds (3-6) are rare furan derivatives in the plant kingdom with diverse long-chain hydrocarbyl groups as substituents at C-4. All isolated compounds were evaluated for their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1-6 showed significant antiproliferative effects against various human cancer cell lines with IC50 values ranging from 0.28 to 12.06 µM. These findings suggest that the discoveries of these novel γ-lactone derivatives and furan derivatives with significant antiproliferative activities isolated from T. heterophyllus could be of great importance to the development of new anticancer agents.

A new polyoxygenated cyclohexene derivative from Artabotrys hainanensis.

A new polyoxygenated cyclohexene derivative, artahainanol A (1), together with three known analogues (2-4), was isolated from the stems and leaves of Artabotrys hainanensis. Among them, 1 is an unusual polyoxygenated cyclohexene containing 14 carbon atoms on the carbon skeleton. All known compounds (2-4) were isolated from the genus Artabotrys for the first time. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1-4 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 2.68 to 18.32 µM.

Bioactive polyoxygenated seco-cyclohexenes from Artabotrys hongkongensis.

Six new polyoxygenated seco-cyclohexenes, artahongkongenes A-F (1-6), together with six known analogues (7-12) were isolated from the stems and leaves of Artabotrys hongkongensis. Their structures were elucidated by extensive spectroscopic methods. All new compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. New seco-cyclohexenes 1-6 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 0.26 to 16.58 µM.

A new indole alkaloid with anti-inflammatory activity from Nauclea officinalis.

A new indole alkaloid, 17-O-methyl-19-(Z)-naucline (1), together with seven known alkaloids (2-8), were isolated from the stems and leaves of Nauclea officinalis. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons their data with those reported in the literature. 17-O-methyl-19-(Z)-naucline (1) showed significant inhibitory activity on nitric oxide production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro with an IC50 value of 3.6 µM.

A new monoterpenoid indole alkaloid from Ochrosia elliptica.

A new monoterpenoid indole alkaloid, 10-methoxyakuammidine (1), together with four known alkaloids (2-5), were isolated from the stems and leaves of Ochrosia elliptica. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. New compound 1 was evaluated for its cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. 1 exhibited inhibitory effects with IC50 values comparable to those of cisplatin.