A pair of new sesquiterpene isomers containing spiro heterocyclic skeleton from plant-derived fungus Botryosphaeria dothidea

A pair of new sesquiterpene isomers containing a spiro heterocyclic skeleton, dothimes A (1) and B (2), together with six known compounds, quindoline (3), (S)-3-(3-indolyl)lactic acid methyl ester (4), dankasterone B (5), dibutyl phthalate (6), (1S,3R,4R,7S)-3,4-dihydroxy-α-bisabolol (7), and p-hydroxybenzaldehyde (8), were isolated from the plant-derived fungus Botryosphaeria dothidea. The structures of all isolated compounds were determined based on extensive spectroscopic analyses, including 1D/2D nuclear magnetic resonance (NMR), and high resolution electrospray ionization mass spectrometry (HRESIMS) data, as well as by comparison with literature reports. Compounds 1 and 2 exhibited inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production with IC₅₀ values of 63.66 and 58.29 μM, respectively.     

Three new koninginins from Trichoderma neokongii 8722

Three new fungal metabolites, named koninginins I (1), J (2) and K (3) together with four known koninginins A (4), B (5), D (6) and E (7), were isolated from solid fermentation products of Trichoderma neokongii 8722. Three new structures were elucidated by extensive spectroscopic methods, including 1D NMR and 2D NMR, and HR-ESI–MS experiments.     

Three new flavonoids from Millettia pachyloba

Two new prenylated isoflavones, pachyloisoflavone A (1), pachyloisoflavone B (2), and a new pterocarpan, pachylobin A (3), together with ten known flavonoids (4–13), were isolated from the vine stems and leaves of Millettia pachyloba. The structures of new compounds were elucidated on the basis of extensive spectroscopic data interpretation, including 1D, 2D NMR and HREIMS. The absolute configuration of 2 was established by the comparison of experimental and calculated electronic circular dichroism (ECD) spectra.     

Cytotoxic triterpene diglycosides from the sea cucumber Stichopus horrens

Using various chromatographic separation techniques, eight triterpene diglycosides (1–8), including four new compounds namely stichorrenosides A–D (1–4), were isolated from a methanol extract of the Vietnamese sea cucumber S. horrens. Their structures were elucidated based on spectroscopic analyses, including HR ESI MS, 1D and 2D NMR. Their in vitro cytotoxic activity against five human cancer cell lines, Hep-G2 (hepatoma cancer), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma), was evaluated using SRB methods. Stichorrenoside D (4), stichoposide A (5), and 3β-O-[β-d-xylopyranosyl-(1→2)-β-d-xylopyranosyl]-23S-acetoxyholost-7-ene (7) showed strong cytotoxicity on all five tested cancer cell lines, whereas significant effect was observed for stichorrenoside C (3) and stichoposide B (6).     

Melanogenesis inhibitory daphnane diterpenoids from the flower buds of Daphne genkwa

Two new daphnane-type diterpene esters, daphneresiniferins A (1) and B (2), along with seven known diterpenes, yuanhuacine (3), yuanhuadine (4), yuanhuahine (5), genkwadaphnin (6), genkwanine A (7), genkwanine F (8), and genkwanine H (9), were isolated from the methanol extract of the flower buds of Daphne genkwa. Their structures were elucidated on the basis of spectroscopic methods, especially 2D NMR spectra such as HMQC, HMBC, and NOESY. All the isolates were evaluated for their inhibitory effects of the melanogenesis against α-melanocyte stimulating hormone (α-MSH)-activated B16 melanoma cells.     

Phenolic compounds from the leaves and stem bark of Pseudospondias microcarpa (A. Rich.) Engl. (Anacardiaceae)

Phytochemical study of the leaves and the stem bark of Pseudospondias microcarpa (A. Rich.) Engl. afforded eight phenolic compounds: scopoletin (1), ferulic acid (2), isovitexin (3), rhoifolin (4), quercetin 3-O-α-L-rhamnopyranoside (5), justicialoside A (6), granduloside A (7) and pithecellobiumol B (8). The structures of the isolated compounds were elucidated by spectroscopic means including 1D and 2D NMR and MS, and by comparison with previously reported data. This is the first report on the isolation of these compounds from the genus Pseudospondias. The chemotaxonomic significance of the isolated compounds within the family Anacardiaceae is discussed.     

Two new flavonol glycosides from the leaves of Cleome viscosa L.

From the leaves of Cleome viscosa L., two new flavonol glycosides, named visconoside A (1) and visconoside B (2), together with six known flavonol glycosides, vincetoxicoside A (3), vincetoxicoside B (4), kaempferitrin (5), kaempferide 3-O-β-d-glucopyranoside 7-O-α-l-rhamnopyranoside (6), kaempferol 3-O-β-d-glucopyranoside 7-O-α-l-rhamnopyranoside (7), and isorhamnetin 3-O-β-d-glucopyranoside (8) were isolated by various chromatography methods. Its chemical structure was elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and compared with literatures.     

Unusual C19-diterpenoid alkaloids from Aconitum vilmorinianum var. patentipilum

Three new C₁₉-diterpenoid alkaloids vilmotenitines A-C (1-3), together with seven known ones, vilmorine D (4), talatizidine (5), isotalatizidine (6), vilmorrianine B (7), vilmorrianine D (8), talatizamine (9), 8-deacetyl-yunaconitine (10), were isolated from Aconitum vilmorinianum var. patentipilum. Vilmotenitines A (1) and B (2) are the second natural occurrences of C₁₉-diterpenoid alkaloids with a unique rearranged six-membered B ring formed by the C₍₈₎–C₍₁₀₎ linkage.     

Ximaosteroids A–D,new steroids from the Hainan soft coral Scleronephthya sp.

One novel uncommon steroid, ximaosteroid A (1), possessing an unusual tetrahydrofuran moiety and three new pregnane steroids, ximaosteroids B–D (2–4), were isolated from the Hainan soft coral Scleronephthya sp. Their structures were elucidated on the basis of detailed spectroscopic (IR, MS, and 2D NMR) analysis and by comparison with those reported in the literature.     

Illigerones A and B,two new long-chain secobutanolides from Illigera henryi W. W. Sm.

Two new long-chain secobutanolides, illigerones A (1) and B (2), together with five known compounds, actinodaphnine (3), cryptodorine (4), β-sitosterol (5), daucosterol (6), and stigmasterol (7) were isolated from Illigera henryi W. W. Sm. The structures of 1 and 2 were identified by HRESIMS, EIMS, 1D/2D NMR, and electronic circular dichroism (ECD) spectra. Compound 1 exhibited the moderate cytotoxic activities against five tumour cells. This is the first report of secobutanolides isolated from plants of Hernandiaceae.     

Steroids from Dysoxylum grande (Meliaceae) leaves

Seven new 23-oxo-cholestane derivatives named as grandol A (1), B (2), C (3), D (4), E (5), F (6), and G (7) were isolated from Dysoxylum grande leaves alongside with a new 3,4-secodammar-4(28)-en-3-oic acid derivative (8). The structures of the compounds were elucidated based on the interpretation of spectroscopic data, and their relative configurations were established by NOESY 2D NMR data. All of the isolates were tested for anti-acetylcholinesterase activity using thin layer chromatography (TLC)-bioautography with fast blue B salt. Only grandol A (1) and B (2) showed positive results, with clear discoloration at a concentration of 12.5 ppm. However, the obtained IC₅₀ values for grandol A and B, when using Ellman’s method, were not significant (>200 μg/ml).     

Phenolic acid glycosides from Parmentiera cereifera Seem. (Candle tree)

Two new phenolic acid glycosides, parmentins A (1) and B (2) were isolated from the methanolic extract of the leaves and stems of candle tree (Parmentiera cereifera Seem). These compounds were accompanied by a mixture of β-sitosterol and stigmasterol (3), β-sitosterol glucoside (4), isovanillic acid (5), vanillic acid (6), and p-hydroxybenzoic acid (7). The structures of the isolated compounds were determined on the basis of physical and spectroscopic analyses, including 1D and 2D NMR (¹H, ¹³C, COSY, HSQC and HMBC) and mass spectrometry (HR-ESI-MS).     

Two new hemiterpene glycosides and one new phenolic glycoside from the roots of Securidaca inappendiculata Hassk

Two new hemiterpene glycosides, named as securiterpenoside B (1), and securiterpenoside C (2), and one new phenolic glycoside, named as securiphenoside A (3) were isolated from the roots of Securidaca inappendiculata Hassk. Their structures were elucidated on the basis of 1D and 2D NMR data and HRESIMS and comparisons with published data. Moreover, compounds 1–3 were evaluated for cytotoxicities against A549 (Lewis lung cancer), Hela (human cervical cancer) and MCF-7 (human breast cancer) cell lines.     

New labdane diterpenoids from Leonurus japonicus and their anti-inflammatory activity

Two new, 16-oxo-leoheteronone A (1) and 15-methoxyleoheteronin B (2), and four known, 8,9-secohispanolone (3), galeopsin (4), hispanone (5), and leoheteronin B (6), labdane diterpenoids were isolated from the aerial parts of Leonurus japonicus. Compound 3 was isolated for the first time as a naturally occurring compound. Structures of the two compounds were determined on the basis of extensive spectroscopic techniques, including 1D, 2D NMR, and HREIMS. In addition, compounds 1–3, 5 and 6 were examined for inhibition of superoxide anion generation and elastase release, and the results suggested that compound 5 possesses anti-inflammatory activity.     

Secondary metabolites from the endophytic fungus Biscogniauxia formosana and their antimycobacterial activity

Two new azaphilone derivatives, namely, biscogniazaphilones A (1) and B (2), along with ten known compounds (3–12), were isolated from the n-BuOH-soluble fraction of the 95% EtOH extract of long-grain rice fermented with the endophytic fungus Biscogniauxia formosana BCRC 33718, derived from the bark of medicinal plant Cinnamomum species. Their structures were elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR as well as HRESIMS, ESIMS, UV, and IR, and comparison with literature data. In addition, the isolated compounds (1–12) were evaluated for their antimycobacterial activity. Two new constituents, biscogniazaphilones A (1) and B (2), exhibited the strongest antimycobacterial activities against Mycobacterium tuberculosis strain H₃₇Rv, with MIC values of 5.12 and 2.52 μg/mL, respectively.     

Triterpene saponins and megastigmane glucosides from Camellia bugiamapensis

Two new triterpene saponins, camelliosides I and J (1 and 2), two new megastigmane glycosides, camellistigosides A and B (3 and 4), and two known megastigmane glycosides, icariside B₁ (5) and (6S,9R)-roseoside (6), were isolated from a methanol extract of the Camellia bugiamapensis leaves using various chromatographic separation techniques. Their structures were elucidated based on spectroscopic analyses, including HR ESI MS, CD, 1D and 2D NMR. Their inhibitory effects on LPS-induced NO production in RAW264.7 cells were evaluated. This is the first report of the chemical constituents and biological activity of C. bugiamapensis.     

Secondary metabolites from the stem bark of Juglans mandshurica

A pair of new dibenz[cd,lm]perylene derivatives, juglanperylenone A (1a) and juglanperylenone B (1b), along with ten known compounds, including four anthraquinones (2–5), two coumarins (6–7) and four triterpenoids (8–11), were isolated from the stem bark of Juglans mandshurica Maxim. Their structures were elucidated on the basis of spectroscopic evidence, including 1D and 2D NMR, HR-TOF-MS, and by comparison with literature data. In addition, the chemotaxonomic significance of the isolates was also discussed in this paper.     

Four new lanostane-type triterpenoids from Inonotus obliquus

Four new lanostane-type triterpenoids, inonotsuoxodiol B (1), inonotsuoxodiol C (2), epoxyinonotsudiol (3), and methoxyinonotsutriol (4), were isolated from the sclerotia of Inonotus obliquus. Their structures were determined to be 3β,22R-dihydroxylanosta-9(11),24-dien-7-one (1), 3β,22R-dihydroxylanosta-7,24-dien-11-one (2), 9α,11α-epoxy-lanosta-7,24-diene-3β,22R-diol (3), and 7β-methoxylanosta-8,24-diene-3β,11α,22R-triol (4) on the basis of NMR spectroscopy, including 1D and 2D (¹H–¹H-COSY, NOESY, HMQC, HMBC) NMR spectra, and EIMS.     

Spicachlorantins A and B,new dimeric sesquiterpenes from the roots of Chloranthus spicatus

Two new lindenane sesquiterpene dimers, spicachlorantins A and B (1 and 2), were isolated from the roots of Chloranthus spicatus along with a known related compound, chloramultilide A (3). Their structures and the absolute stereostructures were established by 1D and 2D NMR as well as by CD spectroscopic analyses.     

5-Hydroxyindole-type alkaloids,as Candida albicans isocitrate lyase inhibitors,from the tropical sponge Hyrtios sp.

Chemical investigations of the tropical marine sponge Hyrtios sp. have resulted in the isolation of a new alkaloid, 1-carboxy-6-hydroxy-3,4-dihydro-β-carboline (1) together with the known metabolites, 6-hydroxy-3,4-dihydro-1-oxo-β-carboline (2), 5-hydroxy-1H-indole-3-carboxylic acid methyl ester (3), serotonin (4), hyrtiosin A (5), 5-hydroxyindole-3-carbaldehyde (6), and hyrtiosin B (7). Their structures were elucidated on the basis of mass spectrometry and detailed 2D NMR spectroscopic data. Hyrtiosin B (7) displayed a potent inhibitory activity against isocitrate lyase (ICL) of Candida albicans with an IC₅₀ value of 89.0 μM.