Synthesis and pharmacological activity evaluation of 2-(2-Phenylethyl)chromone analogues: The principal components in agarwood.

2-(2-Phenylethyl)chromones (PECs), the pivotal constituents responsible for the distinctive aroma and pharmacological potential of agarwood, are primarily obtained through extraction from natural materials. The restricted availability of agarwood has, however, hindered a comprehensive and systematic evaluation of their biological properties. In this study, we have chemically synthesized a total of 38 PEC derivatives, including 23 new compounds that had not been previously isolated from agarwood.

Molecular characterization and structure basis of a malonyltransferase with both substrate promiscuity and catalytic regiospecificity from .

Enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides supply. However, the catalytic potential and structural basis of plant malonyltransferase are far from being fully elucidated. This work identified a new malonyltransferase CtMaT1 from It displayed unprecedented mono- and/or di-malonylation activity toward diverse glucosides with different aglycons.

Discovery of plant chemical defence mediated by a two-component system involving β-glucosidase in Panax species.

Plants usually produce defence metabolites in non-active forms to minimize the risk of harm to themselves and spatiotemporally activate these defence metabolites upon pathogen attack. This so-called two-component system plays a decisive role in the chemical defence of various plants. Here, we discovered that Panax notoginseng, a valuable medicinal plant, has evolved a two-component chemical defence system composed of a chloroplast-localized β-glucosidase, denominated PnGH1, and its substrates 20(S)-protopanaxadiol ginsenosides.

Identification of a diarylpentanoid-producing polyketide synthase in the biosynthesis of 2-(2-phenylethyl)chromones in agarwood.

Agarwood has been valued as an exquisite, high-grade fragrant wood since ancient times. Due to the scarcity of high-quality agarwood, it is quite expensive, and the number of original plants has been drastically reduced due to overharvesting, including illegal logging. Despite this, a reliable method of agarwood cultivation has yet to be developed.

[LC-MS analysis of 2-(2-phenylethyl) chromones in sodium chloride-treated suspension cells of Aquilaria sinensis].

Qualitative and quantitative analysis of 2-(2-phenylethyl) chromones in sodium chloride(NaCl)-treated suspension cells of Aquilaria sinensis was conducted by UPLC-Q-Exactive-MS and UPLC-QQQ-MS/MS. Both analyses were performed on a Waters T3 column(2.1 mm×50 mm, 1.

Gastroprotective 2-(2-phenylethyl)chromone-sesquiterpene hybrids from the resinous wood of Aquilaria sinensis (Lour.) Gilg.

Six previously unprecedented 2-(2-phenylethyl)chromone-sesquiterpene hybrids, aquisinenins A-F (1 - 6), were isolated from the resinous wood of Aquilaria sinensis by a LC-MS-guided fractionation procedure. Their structures were determined by extensive spectroscopic analysis (1D and 2D NMR, UV, IR, and HRMS) and experimental and computed ECD data. Compounds 1 - 6 were rare dimeric 2-(2-phenylethyl)chromone-sesquiterpene derivatives featuring 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromone hybridized with different sesquiterpene (eudesmane/guaiane type) moieties via ester bond.

[Research progress on application of multi-enzyme-catalyzed cascade reactions in enzymatic synthesis of natural products].

As a biocatalyst, enzyme has the advantages of high catalytic efficiency, strong reaction selectivity, specific target products, mild reaction conditions, and environmental friendliness, and serves as an important tool for the synthesis of complex organic molecules. With the continuous development of gene sequencing technology, molecular biology, genetic manipulation, and other technologies, the diversity of enzymes increases steadily and the reactions that can be catalyzed are also gradually diversified. In the process of enzyme-catalyzed synthesis, the majority of common enzymatic reactions can be achieved by single enzyme catalysis, while many complex reactions often require the participation of two or more enzymes.

Characterization of a coumarin -/-prenyltransferase and a quinolone -prenyltransferase from .

Prenyltransferases (PTs) play important roles in the biosynthesis and structural diversification of natural products. In the present study, two new PTs were characterized from a medicinal plant . MePT1 unprecedentedly catalyses the formation of two -geranylated products 8/6--geranylumbelliferone together with a trace product 7--geranylumbelliferone from umbelliferone.

A Multifunctional Cytochrome P450 and a Meroterpenoid Cyclase in the Biosynthesis of Fungal Meroterpenoid Atlantinone B.

The biosynthetic gene cluster of atlantinone B () was discovered in MT-40. A multifunctional cytochrome P450 (AtlD) encoded by the cluster is responsible for the formation of the unique lactone-bridged ring and the 16β-hydroxyl of atlantinone B, and a new terpene cyclase (AtlC) can unprecedentedly accept the demethylated substrate epoxyfarnesyl-DMOA () to generate three bicyclic meroterpenoids (-). This study paves the way for combinatorial synthesis of structurally diverse meroterpenoids for drug discovery.

Identification of a diarylpentanoid-producing polyketide synthase revealing an unusual biosynthetic pathway of 2-(2-phenylethyl)chromones in agarwood.

2-(2-Phenylethyl)chromones (PECs) are the principal constituents contributing to the distinctive fragrance of agarwood. How PECs are biosynthesized is currently unknown. In this work, we describe a diarylpentanoid-producing polyketide synthase (PECPS) identified from Aquilaria sinensis.

Deciphering the Biosynthetic Mechanism of Pelletierine in Alkaloid Biosynthesis.

Pelletierine, a proposed building block of alkaloids (LAs), was demonstrated to be synthesized via the non-enzymatic Mannich-like condensation of Δ-piperideine and 3-oxoglutaric acid produced by two new type III PKSs (HsPKS4 and PcPKS1) characterized from and , respectively. The findings provide new insights for further understanding the biosynthesis of LAs such as huperzine A.

Two new diterpenoids from MT-12, an endophytic fungus isolated from .

Two new diterpenoids, penicichrysogene A () and penicichrysogene B (), were isolated from the solid substrate fermentation cultures of MT-12, an endophytic fungus isolated from the medicinal plant of . Their structures were elucidated on the basis of extensive spectroscopic and spectrometric data (1D and 2D NMR, UV, IR, and HRESIMS). The absolute configurations of and were assigned on the basis of experimental and calculated electronic circular dichroism spectra.

[Isolation and identification of endophytic fungi from Huperzia serrata and their metabolites' inhibitory activities against acetylcholinesterase and anti-inflammatory activities].

A total of 27 endophytic fungal strains were isolated from Huperzia serrata,which were richly distributed in the stems and leaves while less distributed in roots. The 27 strains were identified by Internal Transcribed Spacer( ITS) r DNA molecular method and one of the strains belongs to Basidiomycota phylum,and other 26 stains belong to 26 species,9 general,6 families,5 orders,3 classes of Ascomycota Phylum. The dominant strains were Colletotrichum genus,belonging to Glomerellaceae family,Glomerellales order,Sordariomycetes class,Ascomycota Phylum,with the percentage of 48.

LC-MS-guided isolation of anti-inflammatory 2-(2-phenylethyl)chromone dimers from Chinese agarwood (Aquilaria sinensis).

Fifteen previously undescribed 2-(2-phenylethyl)chromone dimers, along with two known analogues were isolated from Chinese agarwood (Aquilaria sinensis) by a LC-MS-guided fractionation procedure. Their structures were elucidated on the basis of spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS). The isolated compounds exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.

Crystalline Sponge Method Enabled the Investigation of a Prenyltransferase-terpene Synthase Chimeric Enzyme, Whose Product Exhibits Broadened NMR Signals.

By the genome-mining approach, a chimeric enzyme of prenyltransferase-diterpene synthase was discovered from Penicillium chrysogenum MT-12. Since its product exhibited broadened NMR signals, the structural determination by only the NMR analysis was difficult, but the crystalline sponge method successfully revealed the structure with a 6-5-5-5 fused ring system. This demonstrated that the collaboration between the genome-mining and crystalline sponge method has the potential to facilitate rapid inquiries into the unexplored chemical space of small molecules.

Megastigmane glycosides from Urena lobata.

Five new megastigmane glycosides, urenalobasides A-E (1-5), together with 11 known ones (6-16) were isolated from Urena lobata. Their structures were determined by extensive spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism method. Compounds 1 and 2 are two unusual megastigmanes structurally containing a 6/5 fused ring system.

Anti-inflammatory Dimeric 2-(2-Phenylethyl)chromones from the Resinous Wood of Aquilaria sinensis.

Sixteen new 2-(2-phenylethyl)chromone dimers, including four pairs of enantiomers (1a/1b, 3a/3b, 6a/6b, and 8a/8b), along with eight optically pure analogues (2, 4, 5, 7, and 9-12) were isolated from the resinous wood of Aquilaria sinensis. Their structures were determined by extensive spectroscopic analysis (1D and 2D NMR, UV, IR, and HRMS) and experimental and computed ECD data. Compounds 1-10 feature an unusual 3,4-dihydro-2 H-pyran ring linkage connecting two 2-(2-phenylethyl)chromone monomeric units, while compounds 11 and 12 possess an unprecedented 6,7-dihydro-5 H-1,4-dioxepine moiety in their structures.

[Cloning and expression analysis of transcription factor AsMYB1 and AsMYB2 from Aquilaria sinensis].

The MYB gene family comprises one of the richest groups of transcription factors in plants. The full length of two MYB genes were isolated through heterologous screening of Aquilaria sinensis calli transcriptome data, and the reverse transcription PCR was performed to obstain the corrected MYB clones, named AsMYB1, AsMYB2. The MYB transmembrane domain and phylogenetic analysis were predicted by different software to analyze the bioinformatics of MYB proteins.

Nitric oxide inhibitory polyketides from Penicillium chrysogenum MT-12, an endophytic fungus isolated from Huperzia serrata.

Twelve new polyketides, penicichrysogenins A-L (1-10, 11a, and 11b) along with five known compounds (12a, 12b, and 13-15) were isolated from the solid substrate fermentation cultures of a Huperzia serrata endophytic fungus Penicillium chrysogenum MT-12. The structures of the new compounds were established using extensive spectroscopic (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) methods. Compounds 11a/11b and 12a/12b were two pairs of enantiomers successfully separated by chiral HPLC resolution.

[Simultaneous determination of 14 organic acids in Shenfu injection by hydrophilic interaction chromatography-tandem mass spectrometry].

Organic acids are widely distributed in plants and related products, and participate in a wide range of metabolic pathways (e.g. tricarboxylic acid cycle), showing diverse pharmacological activities.

Anti-inflammatory 2-(2-phenylethyl)chromone derivatives from Chinese agarwood.

Five new 2-(2-phenylethyl)chromone derivatives (1-5), along with eleven known compounds (6-16) were isolated from Chinese agarwood. Their structures were elucidated by spectroscopic data (NMR, UV, IR, and MS) analyses and comparison of their spectroscopic and physical data with the literature values. The absolute configurations of 2-4 were determined by electronic circular dichroism (ECD) calculations.

Dimeric furanocoumarins from the roots of Angelica dahurica.

Three new dimeric furanocoumarins, dahuribiethrins H-J (1-3), and a new ester coumarin, dahurinol A (4), were isolated from the roots of Angelica dahurica. Their structures were elucidated on the basis of extensive spectroscopic data including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 2 and 3 exhibited inhibition of nitric oxide production in the lipopolysaccharide (LPS)-stimulated RAW 264.

Triterpenoids from the roots of Rubus parvifolius.

Two new oleanane-type triterpenoids, parvifolactone A (1) and rubuside P (2), together with 11 known triterpenoids, fupenzic acid (3), 18,19-seco,2α,3α-dihydroxyl-19-oxo-urs-11,13(18)-dien-28-oic acid (4), euscaphic acid (5), maslinic acid (6), 1β- hydroxyeuscaphic acid (7), 2α,3α,19α,23-tetrahydroxyolean-12-en-28-oic acid (8), 2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid (9), glucosyl pinfaensate (10), rubuside J (11), 2α,3α,19α,23-tetrahydroxyurs-12-en-24,28-dioic acid (12), and 2α,3β,19α- trihydroxyurs-12-en-23,28-dioic acid (13), were isolated from the roots of Rubus parvifolius.

Synthesis of Unnatural 2-Substituted Quinolones and 1,3-Diketones by a Member of Type III Polyketide Synthases from Huperzia serrata.

A curcuminoids, benzalacetone-, and quinolone-producing type III polyketide synthase (HsPKS3) from Huperzia serrata uniquely catalyzes the formation of unnatural 2-substituted quinolones and 1,3-diketones via head-to-head condensation of two completely different substrates. The broad range of substrate tolerance of HsPKS3 facilitates accessing structurally diverse 2-substituted quinolones and 1,3-diketones.