Inhibitory effects of metachromins L–Q and its related analogs against receptor tyrosine kinases EGFR and HER2

Metachromins are a series of sesquiterpenoid quinones isolated from Okinawan marine sponges. Inhibitory effects of metachromins L–Q (1–6), sesquiterpenoid quinones with an amino acid residue, and their related analogs (7–18) prepared from metachromins A (19) and C (20) against receptor tyrosine kinases EGFR and HER2 were investigated. Two analogs 11 and 12 showed relatively stronger inhibitory activity against EGFR, while metachromins L–Q (1-6) and seven analogs (8, 10, 11, and 15–18) showed inhibitory activities against HER2.     

Six kanshone C-derived sesquiterpenoid hybrids nardochalaristolones A–D,nardoflavaristolone A and dinardokanshone F from Nardostachys jatamansi DC.

Four sesquiterpenoid-chalcone hybrids (nardochalaristolones A–D, 1–4), a pair of epimeric sesquiterpenoid-flavonone hybrids ((2′S)- and (2′R)-nardoflavaristolone A, 5 and 6), and a sesquiterpenoid dimer (dinardokanshone F, 7), all sharing a kanshone C-derived sesquiterpenoid unit, were isolated from the underground parts of Nardostachys jatamansi (D.Don) DC. Their structures were elucidated by analysis of the extensive spectroscopic data, and the absolute configurations were established by analysis of 2D NMR spectroscopic data including NOESY data, combined with comparisons of experimental and calculated electronic circular dichroism spectra. Further, the plausible biosynthetic pathways for these compounds were proposed. And the results of SERT activity assay revealed that nardochalaristolones C–D (3 and 4) and nardoflavaristolone A (5 and 6) significantly enhanced SERT activity, while other compounds didn't show any SERT regulatory activities.     

Anti-inflammatory spiroaxane and drimane sesquiterpenoids from Talaromyces minioluteus (Penicillium minioluteum)

A new spiroaxane sesquiterpenoid talaminoid A (1) and two drimane sesquiterpenoid talaminoids B and C (2 and 3), together with four known compounds (4–7), were isolated from the solid culture broth of fungus Talaromyces minioluteum. The structures were determined by extensive 1D and 2D NMR and HRESIMS spectroscopic data analyses, and the absolute configuration of these new compounds were undoubtedly confirmed by X-ray crystal diffrations. Compound 1 is a rare spiroaxane sesquiterpenoid and the absolute configuration of spiroaxane sesquiterpenoid was determined for the first time. Compound 2 is the first drimane-type sesquiterpenoid containing both amino acid residue and butanediol group. Compounds 1, 4, and 5 showed significant suppressive effect on the production of NO on LPS induced BV-2 cells, with IC₅₀ values ranging from 4.97 to 7.81 μM. In addition, 1, 4, and 5 exhibited significant anti-inflammatory activities against the production of TNF-α and IL-6. Further immunofluorescence experiments revealed the mechanism of action to be inhibitory the NF- κB-activated pathway.     

A new secoiridoid glycoside and a new sesquiterpenoid glycoside from Valeriana jatamansi with neuroprotective activity

A new secoiridoid glycoside, isopatrinioside (1) and a new sesquiterpenoid glycoside, valeriananoid F (2), together with nine known compounds, were isolated from the roots of Valeriana jatamansi. Their structures were elucidated on the basis of spectroscopic analysis. Compound 1 was an unusual monocyclic iridoid glycoside ring-opened between C-1 and C-2 produced by the cleavage of the pyran ring. Of the eleven isolates, compounds 1 and 4 exhibited moderate neuroprotective effects against CoCl₂-induced neuronal cell death in PC12 cells.     

Further sesquiterpenoids from the rhizomes of Homalomena occulta and their anti-inflammatory activity

The rhizomes of Homalomena occulta are called Qian-nian-jian in Traditional Chinese Medicine (TCM), which is widely consumed in China owing to its health benefits for the treatment of rheumatoid arthritis and for strengthening tendons and bones. A phytochemical investigation on this famous TCM yielded 19 sesquiterpenoids (1–19) with various carbocyclic skeletons including isodaucane (2, 8, and 9), guaiane (3), eudesmane (4 and 10–15), oppositane (5, 16, and 17), and aromadendrane (18 and 19) types. The structures of new compounds, Homalomenins A-E (1–5), were determined by diverse spectroscopic data. Compound 1 possessed a rare sesquiterpenoid skeleton and compound 5 represented the first example of 1,4-oxa-oppositane sesquiterpenoid. These isolates were evaluated for their inhibitory effects on COX-2 mRNA, COX-2 protein expression, and prostaglandin E2 (PGE2) production in Raw264.7 cells, which demonstrated that compounds 5, 18, 19 showed potent anti-inflammatory activity by suppressing LPS-induced COX-2 expression and PGE2 production in a dose-dependent manner.     

Achyrodimer F,a tyrosyl-DNA phosphodiesterase I inhibitor from an Australian fungus of the family Cortinariaceae

Mass-guided isolation of the dichloromethane/methanol extracts from a specimen of teleomorphic fungus of the family Cortinariaceae resulted in the identification of a new dimeric cyclobutane metabolite, achyrodimer F (1), along with the monomers hispidin (2) and bisnoryangonin (3). Their structures were determined by NMR and MS data analyses. Density Function Theory (DFT) NMR calculations was employed to confirm the chemical structure of achyrodimer F. Compound 1 inhibited tyrosyl-DNA phosphodiesterase I with an IC₅₀ value of 1 μM.     

Pyrinodemins E and F, new 3-alkylpyridine alkaloids from sponge Amphimedon sp

Two new 3-alkylpyridine alkaloids, pyrinodemins E (1) and F (2), were isolated from an Okinawan marine sponge Amphimedon sp. and the structures of 1 and 2 were elucidated on the basis of spectroscopic data. Pyrinodemins E (1) and F (2) were novel 3-alkylpyridine alkaloids possessing a 4-(methoxyamino)piperidinone moiety and an indol-3-glyoxylamide moiety, respectively. Pyrinodemin E (1) showed cytotoxicity against P388 and L1210 murine leukemia cells.     

Paeonidanins F–H: Three new dimeric monoterpene glycosides from Paeonia lactiflora and their anti-inflammatory activity

Three new dimeric monoterpene glycosides, paeonidanins F–H (1–3) were isolated from the roots of Paeonia lactiflora. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. Compounds 1–3 showed inhibitory effects against nitric oxide (NO) and pro-inflammatory cytokine TNF-α release in LPS-induced RAW 246.7 macrophages.     

Eudesmane sesquiterpenoid lactones and abietane diterpenoids from Ajuga forrestii Diels

Four eudesmane sesquiterpenoid lactones (1–4) and seven abietane diterpenoids (5–11) were isolated from the whole plants of Ajuga forrestii. Among them, 3α-acetoxy-1α,8β-dihydroxyeudesm-7(11)-en-8,12-olide (1), 3α-acetoxy-1α-hydroxyl-eudesm-8,7(11)-dien-8,12-olide (2), 1α-acetoxy-8α-oxyethyl-2-oxo-eudesman-3,7(11)-dien-8,12-olide (3) and 2α,3β,11,12-tetrahydroxy-7β,20-epoxy-8,11,13-abietatriene (11) are novel compounds. The structures of compounds 1–11 were determined by spectroscopic analysis. Compound 2 exhibited weak cytotoxicity on HepG2 and MCF-7 cell lines.     

Novel bioactive molecules from Lentzea violacea strain AS 08 using one strain-many compounds (OSMAC) approach

A new eudesmane sesquiterpenoid (1), and a new homologue of virginiae butanolide E (2) along with butyl isobutyl phthalate (3) were isolated from, actinomycete-Lentzea violacea strain AS08 isolated from north western Himalayas by stressing on modified one strain-many compounds (OSMAC) method. The structures of the new compounds were elucidated by extensive spectroscopic analyses including 1D, 2D NMR along with HR-ESI-MS and FT-IR data. Herein, a distinctive method was added for inspecting secretory profile of the strain by quantification of extract value of cell free supernatant in different types of culture media fallowed by HPLC profiling of respective extracts, which revealed a highly altered metabolic profile of the strain and formed the base for the selection of media. The compounds 1 and 2 showed moderate activity against Gram negative (MIC ～32–64 µg ml^?1) in comparison to Gram positive bacterial pathogens. Compound 1 exhibited significant activity in human cancerous cell lines (IC₅₀ ～19.2 µM).     

Hipponorterpenes A and B,two new 14-noreudesmane-type sesquiterpenoids from the juice of Hippophae rhamnoides

Two undescribed sesquiterpenoids, hipponorterpenes A (1) and B (2), and 17 known compounds were obtained from the juice of Hippophae rhamnoides. Their structures were established through comprehensive analysis of their spectroscopic data. Notably, hipponorterpene A (1) is the first 14-noreudesmane-type sesquiterpenoid that has a five-membered lactone between C-4 and C-6. In addition, antiviral activity against herpes simplex virus type 2 (HSV-2) of compounds 1-4 was predicted by molecular docking and hipponorterpene B (2) showed anti-HSV-2 activity.     

Spasmolytic and anti-inflammatory effects of constituents from Hertia cheirifolia

A sesquiterpenoid Bakkenolide (1), and two steroids, (3β, 22E)-Stigmasta-5, 22-diène-3-ol (Stigmasterol) (2) and stigmasterol 3β-glucoside (3), isolated from the Hertia cheirifolia (L.) chloroform extract, were evaluated respectively for their spasmolytic and anti-inflammatory activities. We note that these natural products were isolated and purified for the first time from the specie Hertia cheirifolia. Their structures have been established by spectroscopy (1 and 2D NMR experiences) and mass spectrometry. Chloroform-, ethyl acetate- and methanol-extracts were also tested for their spasmolytic and anti-inflammatory activities. Spasmolytic and anti-inflammatory screening were based respectively on the contractile response effects on rat isolated smooth muscles and on the dose-related carrageenan induced paw edema in rats. screening of the crude extracts showed spasmolytic and anti-inflammatory positive results. The antispasmodic effect of Bakkenolide was found in the same range as that of Alverine, a standard musculotropic spasmolytic agent.     

Spasmolytic and anti-inflammatory effects of constituents from Hertia cheirifolia

A sesquiterpenoid Bakkenolide (1), and two steroids, (3β, 22E)-Stigmasta-5, 22-diène-3-ol (Stigmasterol) (2) and stigmasterol 3β-glucoside (3), isolated from the Hertia cheirifolia (L.) chloroform extract, were evaluated respectively for their spasmolytic and anti-inflammatory activities. We note that these natural products were isolated and purified for the first time from the specie Hertia cheirifolia. Their structures have been established by spectroscopy (1 and 2D NMR experiences) and mass spectrometry. Chloroform-, ethyl acetate- and methanol-extracts were also tested for their spasmolytic and anti-inflammatory activities. Spasmolytic and anti-inflammatory screening were based respectively on the contractile response effects on rat isolated smooth muscles and on the dose-related carrageenan induced paw edema in rats. screening of the crude extracts showed spasmolytic and anti-inflammatory positive results. The antispasmodic effect of Bakkenolide was found in the same range as that of Alverine, a standard musculotropic spasmolytic agent.     

Acylphloroglucinol derivatives from Hypericum laricifolium Juss

A new dimeric acylphloroglucinol derivative, hyperlaricifolin (1), and two new monomeric acylphloroglucinols, laricifolin A (2) and laricifolin B (3), were isolated from an extract of the aerial parts of Hypericum laricifolium Juss., along with the four known dimeric acylphloroglucinols uliginosin B, isouliginosin B, hyperbrasilol B, and isohyperbrasilol B. Their structures were elucidated by interpretation of their 1D-, 2D-NMR and mass spectra.     

Phytochemicals with NO inhibitory effects and interactions with iNOS protein from Trigonostemon howii

A phytochemical investigation to obtain new NO inhibitors led to the isolation of nine compounds including one new guaiane-type sesquiterpenoid (1) and two new cleistanthane diterpenoids (2 and 3) from the stems of Trigonostemon howii. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analysis, and the absolute configurations of new compounds 1–3 were established via comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 2 and 3 possess a rare 3,4-seco-cleistanthane diterpenoid skeleton. All of the compounds showed inhibitory effects on lipopolysaccharide-induced NO production in murine microglial BV-2 cells. The further molecular docking studies indicated the strong interactions between some bioactive compounds with the iNOS protein, which revealed the possible and potential mechanism of NO inhibition of bioactive compounds.     

New prenylated dihydrochalcones from the leaves of Artocarpus elasticus

The leaves of Artocarpus elasticus collected in Thailand were investigated for chemical constituents. Four new prenylated dihydrochalcones named elastichalcones C, D, E, F (1, 3, 5, 6) together with elastichalcone B (2) and artocarpanone (4) were isolated. Their structures were determined from analysis of spectroscopic data. Elastichalcone C (1) exhibited good antibacterial activity and cytotoxicity.     

Bioactive constituents of Morus wittiorum

From the stem bark of Morus wittiorum, one new Diels–Alder type adduct wittiorumin G (1) and three new 2-arylbenzofuran derivatives wittifurans P–R (2–4) along with five known Diels–Alder type adducts albafuran C, sorocein A, mulberrofuran E, mulberrofuran F and mulberrofuran O were isolated. Their structures were determined on the basis of spectroscopic analysis. Compounds 2–4 and two known compounds sorocein A and mulberrofuran F were evaluated for their antioxidant activity in a Fe²⁺/cysteine-induced microsomal lipid peroxidation assay and cytotoxicity against five human cancer cell lines respectively.     

Three new cytotoxic sesquiterpenoids from Solanum lyratum

In our continuing effort to discover more new cytotoxic sesquiterpenoid from Solanum lyratum collected from different districts of China, three new sesquiterpenoids, attributable to eudesmane-type (1, named solajiangxin D) and vetispirane-type (2–3, named solajiangxins E and 2-hydroxysolajiangxin E), respectively, were isolated. Their structures were elucidated on the basis of integrated spectroscopic techniques, mainly HR-FABMS, 1D and 2D NMR (¹H–¹H COSY, HMQC, HMBC and ROESY). In vitro, compounds 1–3 were found to show significant cytotoxicities against three human cancer lines (P-388, HONE-1, and HT-29), and gave ED₅₀ values in the range 2.1–3.7 μg/ml.     

Unusual new phenylethanoid and phenylpropanoid diglycosides from the leaves of Chloranthus spicatus (Thunb.) Makino

Chloranthus spicatus (Thunb.) Makino (Chloranthaceae) has been used to treat aches, trauma, and bleeding in Traditional Chinese Medicine. Phytochemical investigation of the leaves of this plant led to the isolation an unusual new phenylethanoid diglycoside, spicaoside (1), and a new phenylpropanoid diglycoside, 1-allyl-3-methoxy-4- [apiofuranosyl(1 ⿿ 2)-glucopyranosyloxybenzene] (2), along with two known sesquiterpenoid glycosides, chloranoside A (3) and chloranthalactone E 8-O-β-d-glucopyranoside (4). Their structures were established by spectroscopic means. New compounds 1 and 2 showed moderate tyrosinase inhibitory activities with the IC₅₀ value of 15.4 μM and 29.1 μM. This study represents the first report of glycoside from C. spicatus.