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In this study, analysis of the chemical constituents and bioactivities of the unpolar fractions [petroleum ether (PE) and chloroform (C)] of fruits and leaves of Alpinia oxyphylla Miq. were carried out, as well as the bioactivities of the main compounds nootkatone and valencene. From PE and C fractions of the fruits, and PE fraction of the leaves, 95.80%, 59.30%, and 82.11% of the chemical constituents respectively were identified by GC-MS. Among these identified compounds, nootkatone was the main compound in all of three fractions, while valencene was the second main compound in the PE fractions of the fruits and leaves. The bioactivities results showed that all of the fractions and the major compound nootkatone showed tyrosinase inhibitory, as well as inhibitory effect on NO production in LPS-stimulated RAW264.7 cells. While valencene only presented inhibitory activity on NO production in RAW264.7 cells. The critical genes involved in nootkatone biosynthesis in A. oxyphylla were identified from the public transcriptome datasets, and protein sequences were preliminarily analyzed. Our studies develop the usage of the unpolar fractions of A. oxyphylla, especially its leaves as the waste during its production, and meanwhile provide the gene resources for nootkatone biosynthesis. [ABSTRACT FROM AUTHOR]

Three new 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones and one new dimeric 2-(2-phenylethyl)chromone were isolated from the agarwood of Aquilaria crassna Pierre ex Lecomte in Laos. The structures of the isolates were elucidated by spectroscopic methods, and their configurations were determined via ROESY correlations, 3JH-H coupling constants analyses, comparisons of chemical shifts and specific rotations with known compounds, and ECD calculation in the case of 1. Compounds 1–4 were evaluated for their cytotoxicity. Compounds 1 and 2 exhibited weak cytotoxicity toward HeLa cell line (IC50: 49.8 ± 1.2 μM) and K562 cell line (IC50: 42.66 ± 0.47 μM), respectively. [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids (1 and 2), together with two known sesquiterpenoids (3 and 4), were isolated from agarwood originated from Aquilaria sp. Their structures were elucidated by extensive spectroscopic methods including 1D and 2D NMR, IR, HRESIMS, and comparison with the literatures. All compounds were evaluated for cytotoxicity against five human cancer cell lines, but none of them displayed significant activity. [ABSTRACT FROM AUTHOR]

• A phytochemical investigation on the agarwood of Aquilaria crassna was performed. • Three new 2-(2-phenylethyl)chromones were isolated and identified. • Compound 2 exhibited inhibitory potency on tyrosinase. • None of the isolates displayed remarkable cytotoxicity. In our ongoing effort to study the metabolites from agarwood of Aquilaria crassna Pierre ex Lecomte (Thymelaeaceae) produced in Laos, three new 2-(2-phenylethyl)chromone derivatives (1 − 3) were isolated. Their structures were elucidated by comprehensive spectroscopic analyses, predominantly by 1D and 2D NMR spectroscopic methods, and by comparison with the reported data. Compound 2 exhibited tyrosinase inhibitory activity with IC 50 value of 172.6 ± 1.7 μM (kojic acid as the positive control, 46.1 ± 1.3 μM) and its inhibition mode was clarified by molecular modelling study. None of the isolates showed significant cytotoxicity towards tested cancer cell lines. [ABSTRACT FROM AUTHOR]

Three new flavanoids, (2R)-7,4'-dihydroxy-8-methylflavan (1), (2R)-7,4'- dihydroxy-6-methylflavan (2), and (3R)-7,3',4'-trihydroxyhomoisoflavan (3), together with seven known compounds (4-10), were isolated from artificially induced dragon's blood of Dracaena cambodiana, and their structures were determined based on HR-ESI-MS and extensive spectroscopic techniques (UV, IR, 1D-, and 2D-NMR). Compound 2 exhibited weak cytotoxicity against BEL-7402 cells line with the IC50 value of 39.2 µM. In addition, compound 3 showed significant acetylcholinesterase (AChE) inhibitory activity. [ABSTRACT FROM AUTHOR]

Seven new 2-(2-phenylethyl)chromone derivatives ( 1 – 7 ) including a chlorinated one ( 4 ), together with eight known ones ( 8 – 15 ), were isolated from the EtOAc extract of artificial agarwood originating from Aquilaria sinensis (Lour.) Gilg. All structures including the absolute configurations were unambiguously elucidated by spectroscopic (NMR, UV, IR, MS) methods, Mosher's method, and comparison with reported data in the literatures. Among those, compounds 8 , 12 , and 14 exhibited significant inhibition against α -glucosidase in vitro with IC 50 values of 0.15, 0.05, and 0.09 mM, respectively (with acarbose as the positive control; IC 50 : 0.98 mM). In addition, compounds 3 , 9 , 11 , and 14 showed weak inhibitory activity against AChE; and compounds 12 and 13 displayed weak cytotoxicity against human gastric cell line (SGC-7901) among three types of tested human cancer cell lines (BEL-7402, K562, and SGC-7901). [ABSTRACT FROM AUTHOR]

Six new 2-(2-phenylethyl)chromone dimers (1 – 6) were isolated from ethyl ether extract of red soil agarwood of Aquilaria crassna from Vietnam by LC-MS-guided fractionation procedure. Their structures were unambiguously elucidated based on HRESIMS, 1D and 2D NMR spectra. The absolute configuration of 2-(2-phenylethyl)chromone dimers was determined by comparison of the experimental and computed ECD spectra. Compound 6 displayed cytotoxicity against the human myeloid leukemia cell line (K562) with an IC 50 value of 39.49 μM. [Display omitted] • Six new dimeric 2-(2-phenethyl)chromones were identified from red soil agarwood of Aquilaria crassna. • The absolute configuration was determined by comparison of the experimental and computed ECD spectra. • Compounds 6 exhibited cytotoxicity against human myeloid leukemia cell line K562. [ABSTRACT FROM AUTHOR]

Fourteen compounds were isolated from the ethanol extract of Dalbergiae Odoriferae Lignum by various chromatographic techniques, including column chromatographies on silica gel, Sephadex LH-20 and semi-preparative HPLC. Their structures were determined by spectroscopic techniques as S-3'-hydroxy-7,2',4'-trimethoxyisoxane(1), 2-(2',4'-dimethoxyphenyl)-6-hydroxybenzofuran(2), 2-(2'-hydroxy-4'-methoxyphenyl)-6-methoxybenzofuran(3), 7,2',4'-trimethoxydihydroisoflavone(4), sativanone(5), 3,9-dimethoxy-6H-benzofuro[3,2-c]chromen-6-one(6),(6 aS,11 aS)-homopterocarpin(7),(6 aS,11 aS)-8-hydroxy-3,9-dimethoxypterocarpan(8),(6 aS,11 aS)-3,8,9-trimethoxypterocarpan(9), isodalbergin(10), isoliquiritigenin(11), butein(12), butin(13) and 3,7,4'-trihydroxyflavone(14). Among them, compound 1 was a new compound, while 2 and 3 were new natural products, 6, 8, 9 and 14 were isolated for the first time from Dalbergiae Odoriferae Lignum. Compounds 1-14 were tested for their cytotoxic activity against human hepatoma cell line BEL-7402, human gastric cancer cell line SCG-7901, human lung cancer cell line A549, human chronic myeloid leukemia cell line K562 and HeLa human cervical cancer cellline by MTT method. Compound 1 exhibited significant cytotoxicity with IC_(50) values ranging from 2.85 to 11.62 μg·mL~(-1). In addition, 2, 11 and 12 showed weak cytotoxic activities.

Six compounds were isolated from the aerial part of cultivated Clerodendranthus spicatus in Hainan with various chromatographic techniques,and their structures were determined as:1-dehydroxy-1-oxo-rupestrinol(1),N-trans-feruloyltyramine(2),methyl 3,4-dihydroxyphenyllactate(3),caffein acid(4),methyl caffeate(5) and ethyl caffeate(6),via analysis of physicochemical properties and spectroscopic evidence.Compound 1 was a new compound,while compounds 2 and 3 were isolated from C.spicatus for the first time.Biological activity results showed that compounds 2-4 exhibited α-glucosidase inhibitory activity with different inhibition ratio.