Bioactive Compounds from Taiwania cryptomerioides

Abstract

Two new sesquiterpenes, 10 alpha-hydroxyamorphan-4-en-3-one (1) and 4 alpha-methylcadinane-4 alpha-methyl-1 alpha,2 alpha,10 alpha-triol (2), together with four known compounds, sesquiterpenes 10 alpha-hydroxycadinan-4-en-3-one (3) and alpha-cadinol (4), diterpene ferruginol and lignan helioxanthin, were isolated from the whole plant of Taiwania cryptomerioides under bioassay-guided fractionations. The structures of 1 and 2 were elucidated mainly by the NMR spectroscopic analyses. Bioactivities of the isolated compounds against brine shrimp, yellow fever mosquito larvae, and human tumor cells are reported; compound 4 was the most bioactive, showing selectivity for the human colon tumor cell line (HT-29).

Xanthone and Sesquiterpene Derivatives from the Fruits of Garcinia scortechinii

“…The coupling constant of 6.3 Hz between H-5 and H-6 provided evidence for the cis-fusion: in trans-fusion, H-5 appeared as a broad singlet, while for cis-fusion, H-5 resonated as a doublet with a coupling constant of 6.5 Hz. 8 Since H-6 appeared as a doublet of doublets of doublets with the large coupling (J ) 10.2 Hz) and the smallest coupling (J ) 5.1 Hz) constants with H-7 and H-1, respectively, H-6 and the 7-isopropyl substituent were located at the -axial and -equatorial positions, respectively. Irradiation of H ax -6 produced signal enhancement of H eq -1 and 10-OMe, supporting the assignment of cis-fusion and also indicating the location of 10-OMe at the -axial position, cis to both H eq -1 and H ax -6.…”

“…9 The 1 H and 13 C NMR and DEPT data revealed that 9 had the skeleton of a cadinane type sesquiterpene. 8,9 Comparison of these data with those of 10R-hydroxyamorphane-4-en-3-one 8,10 indicated that the hydroxyl group of 10R-hydroxyamorphane-4-en-3-one was replaced by an O-methyl group in 9. This demonstrated that the methoxyl group was located at C-10, which was proved by an HMBC correlation between the methoxy protons and C-10.…”

“…12 In 2001, Wu et al proposed a plausible biosynthesis of the gaudispirolactone, the first degraded xanthone isolated from G. gaudichaudii. 13 Isolation of the highly rearranged xanthones (5)(6)(7)(8) might provide insight in the biosynthesis of these molecules.…”

Structure-activity relationships of cadinane-type sesquiterpene derivatives against wood-decay fungi

“…On the other hand, Labbe et al (1993) demonstrated that T-cadinol shows significant toxicity to Artemia salina (brine shrimp bioassay). He et al (1997) reported that a-cadinol showed bioactivity against brine shrimp, yellow fever mosquito (Aedes aegypti) larvae, and human tumor cells . Similarly, in previous studies we found that a-cadinol was moderately active against HT-29, and T-muurolol was modestly active against both the HT-29 and MCF-7 cell lines (Chang et al 2000b).…”

An ethnopharmacological survey conducted in the Bolivian Amazon, and identification of N-alkylamides and lignans from Lepidium meyenii and Heliopsis helianthoides var. scabra with effects on the central nervous system

“…Helioxanthin (10), an arylnaphthalene derivative, was identified earlier from the root of this species 52 and from thirteen other plants. 89,148,[157][158][159][160][161][162][163][164][165][166][167] The dibenzylbutyrolactone helianthoidin was isolated previously 53 …”