Benzylisoquinoline alkaloids with their antitumor activity from the aerial parts of Corydalis impatiens (pall.) Fisch.

Phytochemical investigation on the aerial parts of Corydalis impatiens (pall.) Fisch (Papaveraceae) resulted in the identification of four previous undescribed benzylisoquinoline alkaloids, impatienines A-D (1-4), together with 14 known analogues (5-18). The structures of these compounds were elucidated by extensive spectroscopic analysis (IR, HR-ESIMS, 1D- and 2D-NMR) as well as ECD calculations. All the compounds obtained were investigated for their inhibitory effect on the growth of A549, H1299 and HepG2 cancer cells. Compounds 7 and 15 exhibited pronounced inhibition against the A549 cancer cells with IC50 values of 6.81 µM and 3.17 µM, while the positive control cisplatin was 1.83 µM. Compounds 1-3 showed moderate inhibitory on the H1299 cancer cells. Compounds 4, 10-12, and 16 showed signiffcant activity against HepG2 cancer cells with IC50 values range of 4.41-8.75 µM.

Nitrogenous chemical constituents and their antitumor activities evaluation in vitro from the aerial parts of Corydalis impatiens (pall.) Fisch.

Four new compounds, impatienines E-H (1-4), together with 18 known ones (R)-N-methylcoclaurine (5), impatienine I (6), thalifoline (7), iseluxine (8), pisoquinoline (9), corydaldine (10), northalifoline (11), noroxyhydrastinine (12), 6,7-methylenedioxy-1(2H)-isoquinolinone (13), N-methylcorydaldine (14), oxyhydrastinine (15), corypalline (16), N-trans-feruloylmethoxytyramine (17), N-trans-feruloyldopamine (18), N-trans-feruloyltyramine (19), N-trans-sinapoyltyramine (20), N-cis-feruloyltyramine (21), N-cis-sinapoyltyramine (22) were obtained from the aerial parts of Corydalis impatiens (pall.) Fisch. Their structures were elucidated by extensive spectroscopic analysis (1D- and 2D-NMR, HR-ESIMS, IR, UV) and/or comparison with reported literature. The inhibitory effects of these isolates were also evaluated against the growth of cancer cells (A549, H1299 and HepG2). Compounds 2 and 4 showed significant inhibitory effect on HepG2 cancer cells with IC50 values of 8.62, 8.32 µM, respectively (positive control cisplatin: IC50, 6.32 µM). Compounds 22 and 4 exhibited moderate inhibitory effects against A549 cancer cells, and the IC50 values were 7.78 and 12.54 µM, respectively (positive control cisplatin: IC50, 1.83 µM).

Cistadesertosides B-E, Four New Diastereomeric Lignan Glycosides from the Stems of Cultural Cistanche deserticola in Tarim Desert.

Four previously undescribed diastereomeric lignan glycosides, namely cistadesertosides B-E (1-4) were isolated from the stems of cultural Cistanche deserticola in Tarim desert. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses, including IR, HR-ESI-MS, 1D and 2D NMR, circular dichroism (CD) data and chemical degradation. The in vitro anti-inflammatory activity of the isolates was also investigated. It showed that compounds 3 and 4 exhibited potential effects with IC50 values of 21.17 µM and 26.97 µM, respectively (positive control quercetin, IC50 , 10.01 µM).

Secondary Metabolite Analysis of Phomopsis sp. LGT-5 Based on the Dual Guidance of Whole-Genome Sequencing and HPLC-Q-ToF-MS/MS.

Microorganisms produce a wealth of structurally diverse specialized metabolites with a remarkable range of biological activities. The Phomopsis sp. LGT-5 was obtained through tissue block and repeatedly crossed methods from Tripterygium wilfordii Hook. F. The antibacterial experiments of LGT-5 showed that it has high inhibitory activity against Staphylococcus aureus and Pseudomonas aeruginosa, and moderate inhibitory activity against Candida albicans. To research the generation of the antibacterial phenomenon of LGT-5 and provide support for further research and application, the whole genome sequencing (WGS) of LGT-5 was obtained by single-molecule real-time DNA sequencing platform Pacific Biosciences (PacBio) sequencing and Illumina paired-end sequencing. The final assembled LGT-5 genome is 54.79 Mb with a contig N50 of 290.07 kb; in addition, its secondary metabolites were detected through HPLC-Q-ToF-MS/MS. By comparing its MS/MS data, the secondary metabolites were analyzed based on visual network maps obtained on the Global Natural Products Social Molecular Networking (GNPS). The analysis results showed that the secondary metabolites of LGT-5 were triterpenes and various cyclic dipeptides.

Native Endophytes of Tripterygium wilfordii-Mediated Biotransformation Reduces Toxicity of Celastrol.

Celastrol (1), obtained from the roots of Tripterygium wilfordii Hook F., is most likely to become an antitumor drug, but with severe cytotoxicity. Due to the lack of modifiable sites in the structure of celastrol, the structural diversity of the modified products obtained by synthesis in the previous studies is insufficient, which hinders the pace of its patent medicine. This study describes a method of microbial transformation to increase the modification site of celastrol and reduce its toxicity. The screening of endophytes from native plants was introduced in this context, which led to two novel stereoselective oxidation products such as S-16-hydroxyl celastrol (2) and A-ring aromatized S-16-hydroxyl celastrol (3), along with a rare 7,9-octadecadienoic acid ester of celastrol (4). Their structures were determined by extensive spectroscopic data analysis, especially 1D and 2D NMR. Compared with 1, compounds 3 and 4 exhibited similar antitumor activity in U251, A549, KG-1, and B16 cell lines. Compound 2 had slightly decreased antitumor activity when compared with compound 1. Furthermore, compound 2-4 showed lower cytotoxicity against BV-2 (about 21-fold lower, 2: 92.82 µM, 3: 34.25 µM, and 4: 74.75 µM vs. celastrol: 4.35 µM), and also identical trends against H9c2 and PC12 cell lines.

Classification of diterpenoid alkaloids from Aconitum kusnezoffii Reichb. by liquid chromatography-tandem mass spectrometry-based on molecular networking.

Trace amounts of components in traditional Chinese medicine are considered pharmacological active substances used for treating many serious diseases. However, purifying all the trace substances and making clear their structures are not easy. In this context, high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry based molecular networking was applied to investigate the chemical constituents of the roots of Aconitum kusnezoffii Reichb., which led to the identification of 33 nodes in different groups (N1-N33). Based on the excremental fragmentation pathway of known diterpenoid alkaloids (1-9) and comparisons of characteristic ions and characteristic loss of analogs in literature, the structures of unknown ions were deduced. This work lays a foundation for the evaluation of the clinical basis and mechanism of traditional Chinese medicine from the aspects of chemistry. In this paper, the method speculation of unknown natural products by means of molecular network method is expected to be applied in the discovery and change law of relevant active components in clinical pharmacology and the change of complex systems caused by trace active compounds.

[Research progress on chemical constituents and pharmacological studies on root bark of Lycium barbarum].

Lycii Cortex, the dry root bark of Lycium barbarum(Solanaceae), is rich in chemical compositions with unique structures, such as organic acids, lipids, alkaloids, cyclopeptides and other components, and plays an important role in traditional Chinese medicine. It has the effect of cooling blood and removing steam, clearing lung and reducing fire. It is mainly used in the treatment of hot flashes due to Yin deficiency, hectic fever with night sweat, cough, hemoptysis and internal heat and diabetes. Modern pharmacological studies have shown that the crude extract or monomer of Lycii Cortex has a variety of pharmacological activities, such as hypoglycemic, hypotensive, hypolipidemic, antibacterial, and antiviral effects. In this paper, the chemical constituents and pharmacological effects of Cortex Lycii were reviewed in order to further clarify its effective substances, promote the development of medical undertakings, and ensure the "Healthy China" plan.

[A new 9,19-cycloartane glycoside from Asplenium ruprechtii].

Chemical constituents of water extracts of Asplenium ruprechtii were investigated. Five compounds were isolated by silica gel, Sephadex LH-20 gel column chromatographies and preparative HPLC, and their structures were identified by various spectral analyses as aspleniumside G(1), trans-p-coumaric acid(2), trans-p-coumaric acid 4-O-ß-D-glucoside(3), cis-p-coumaric acid 4-O-ß-D-glucoside(4), and(E)-ferulic acid-4-O-ß-D-glucoside(5). Among them, compound 1 is a new 9,19-cycloartane glycoside.

HPLC coupled with quadrupole time of flight tandem mass spectrometry for analysis of glycosylated components from the fresh flowers of two congeneric species: Robinia hispida L. and Robinia pseudoacacia L.

Developing methods for the systematic and rapid identification of the chemical compositions of fresh plant tissues has long attracted the attention of phytochemists and pharmacologists. In the present study, based on highly efficient sample pretreatment and high-throughput analysis of high-performance liquid chromatography coupled with quadrupole time of flight tandem mass spectrometry data using molecular networks, a method was developed for systematically analyzing the chemical constituents of the fresh flowers of Robinia hispida L. and Robina pseudoacacia L., two congeneric ornamental species that lack prior consideration. A total of 44 glycosylated structures were characterized. And on the basis of establishing of the fragmentation pathways of 11 known flavonoid glycosides, together with the molecular networking analysis, 18 other ions of flavonoid glycosides in five classes were clustered. Moreover, 15 soyasaponins/triterpenoid glycosides were tentatively identified by comparison of their tandem mass spectrometry characteristic ions with those reported in the literature or the online Global Natural Product Social Molecular Networking database. The water extracts were separated by flash chromatography, which resulted in the discovery of one new compound, named rohispidascopolin, along with five known entities. The pharmacological targets were predicted by SwissTargetPrediction.

Structural Determination of a New Cycloartane Glycoside from Asplenium ruprechtii.

We characterized a new cycloartane glycoside, herein known as aspleniumside F (1), along with five known compounds as kaempferol-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-galacopyranoside (2), quercetin-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (3), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (4), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (5), and kaempferol-3-O-[(6-O-p-coumaroyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (6), from Asplenium ruprechtii Sa. Kurata, a folk medicine widely used to treat Thromboangiitis obliterans in China, Japan, and Korea. Based on spectroscopic, mainly 1D-, 2D-NMR and (+)-HR-ESI-MS, analyses as well as through comparisons with previous reports, its chemical structure was determined as 3ß,24,30-tri-ß-D-glucopyranosyl-23,25-dihydroxycycloartane (= (23R,24R)-3ß,24-bis-(ß-D-glucopyranosyloxy)-23,25-dihydroxy-9ß-9,19-cyclolanostan-29-yl ß-D-glucopyranoside). According to the 1 H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with D-glucose, all three glycoside groups in 1 were revealed as ß-D-glucopyranosyl. Furthermore, SOD-like antioxidant activity evaluation via IC50 of 12.43, 6.78, 9.12, 6.94 and 4.85 µM revealed that compounds 2-6 had bioactivity.

Structural determination and in vitro tumor cytotoxicity evaluation of five new cycloartane glycosides from Asplenium ruprechtii Sa. Kurata.

Five new cycloartane glycosides, named aspleniumside A - E, were discovered and characterized by re-investigated the remaining extracts of the whole plant of Asplenium ruprechtii Sa. Kurata, a famous folk medicine for treating thromboangitis obliterans in China, Japan, and Korea. Compounds 3-5 possessed the 9,19-seco-cycloartane-9,11-en triterpene aglycone with 3,7(or 23),24,25,30-highly oxidized methylene, methylene or quaternary carbons, that was found in this species for the first time. The stereo-chemistry of all new compounds were fully discussed by extensive analysis of the 1D and 2D NMR data, and comparisons with those data of known compounds. 24R configuration was determined here which indicated the different growing areas of the same species could influence the secondary metabolic behavior, leading to the differences in chemical composition. All glycoside groups were determined as ß-d-glucopyranosyl by 1H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with d-glucose. All the cycloartane glycosides were evaluated against HL-60 and HepG2 cells for cytotoxicity, compounds 1-3, showed potential cytotoxicity with the IC50 in range of 18-60 µM, while the standard sorafenib showed IC50 value of 10.61 ± 0.43 and 13.43 ± 1.12 µM against HL-60 and HepG2, respectively. The results attained in this study indicated that cycloartane glycosides should be the cytotoxicity substance in A. ruprechtii Sa. Kurata, and had the potential to be developed as tumor cytotoxicity agent applied in clinic.

An anti-inflammatory C-stiryl iridoid from Camptosorus sibiricus Rupr.

A new iridoid glycoside, named camptoside (1), together with three known compounds as dehydrodiconiferyl alcohol-9'-O-ß-d-glucopyranoside (2), aesculetin (3) and vajicoside (4), have been isolated from Camptosorus sibiricus Rupr. (Aspleniaceae). Their structures were established on the basis of spectroscopic analysis, especially 1D- and 2D-NMR data, and by comparison of their spectroscopic and physical data with those reported in the literature. Compounds 1-3 exhibited inhibitions of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values of 11.2, 8.3 and 9.4 µM, respectively.

Structure-based manual screening and automatic networking for systematically exploring sansanmycin analogues using high performance liquid chromatography tandem mass spectroscopy.

Sansanmycins (SS), one of several known uridyl peptide antibiotics (UPAs) possessing a unique chemical scaffold, showed a good inhibitory effect on the highly refractory pathogens Pseudomonas aeruginosa and Mycobacterium tuberculosis, especially on the multi-drug resistant M. tuberculosis. This study employed high performance liquid chromatography-mass spectrometry detector (HPLC-MSD) ion trap and LTQ orbitrap tandem mass spectrometry (MS/MS) to explore sansanmycin analogues manually and automatically by re-analysis of the Streptomyces sp. SS fermentation broth. The structure-based manual screening method, based on analysis of the fragmentation pathway of known UPAs and on comparisons of the MS/MS spectra with that of sansanmycin A (SS-A), resulted in identifying twenty sansanmycin analogues, including twelve new structures (1-12). Furthermore, to deeply explore sansanmycin analogues, we utilized a GNPS based molecular networking workflow to re-analyze the HPLC-MS/MS data automatically. As a result, eight more new sansanmycins (13-20) were discovered. Compound 1 was discovered to lose two amino acids of residue 1 (AA1) and (2S, 3S)-N3-methyl-2,3-diamino butyric acid (DABA) from the N-terminus, and compounds 6, 11 and 12 were found to contain a 2',3'-dehydrated 4',5'-enamine-3'-deoxyuridyl moiety, which have not been reported before. Interestingly, three trace components with novel 5,6-dihydro-5'-aminouridyl group (16-18) were detected for the first time in the sansanmycin-producing strain. Their structures were primarily determined by detail analysis of the data from MS/MS. Compounds 8 and 10 were further confirmed by nuclear magnetic resonance (NMR) data, which proved the efficiency and accuracy of the method of HPLC-MS/MS for exploration of novel UPAs. Comparing to manual screening, the networking method can provide systematic visualization results. Manual screening and networking method may complement with each other to facilitate the mining of novel UPAs.

Polycycloiridals with a Cyclopentane Ring from Iris tectorum.

Six new iridal-type triterpenoids containing an unprecedented cyclopentane ring, polycycloiridals E-J (1-6), were isolated from a large-scale re-extraction of Iris tectorum. A possible biosynthesis pathway is postulated. The known spirioiridotectal D (7) was also obtained in the current investigation, and its structure was unequivocally defined using X-ray diffraction data. Compound 7 suppressed LPS-activated NO production in the BV2 cell line with an IC50 value of 0.54 µM.

[Identification of 3-demethylchuangxinmycin from Actinoplanes tsinanensis CPCC 200056].

Chuangxinmycin (CM) from Actinoplanes tsinanensis was an antibiotic discovered by Chinese scientists about 40 years ago. It contains a new heterocyclic system of indole fused with dihydrothiopyran, whose biosynthetic mechanism remains unclear. CM is used as an oral medicine in the treatment of bacterial infections in China. The simple structure makes CM as an attractive candidate of structure modification for improvement of antibacterial activity. Recently, we analyzed the secondary metabolites of Actinoplanes tsinanensis CPCC 200056, a CM producing strain, as a natural CM analogue. We discovered the first natural CM analogue 3-demethylchuangxinmycin (DCM) as a new natural product. Compared to CM, DCM exhibited a much weaker activity in the inhibition of the bacterial strains tested. The finding provides valuable information for the structure-activity relationship in the biosynthesis of CM.

Polycycloiridals A-D, Four Iridal-Type Triterpenoids with an α-Terpineol Moiety from Iris tectorum.

Polycycloiridals A-D, four novel iridals with an unprecedented α-terpineol moiety resulting from cyclization of the homofarnesylside chain, were isolated from the ethanol extract of rhizomes of Iris tectorum. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. The absolute configuration of 1 was determined by the modified Mosher's method and comparison of experimental and calculated electronic circular dichroism (ECD) spectrum. A possible biosynthetic pathway was postulated.

C14-polyacetylene glucosides from Codonopsis pilosula.

Seven new C14-polyacetylene glucosides codonopilodiynosides A-G (1-7) were isolated from an aqueous extract of the Codonopsis pilosula roots. Their structures were determined by spectroscopic and chemical methods as (-)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5,14-triol 5-O-ß-D-glucopyranoside (1), (-)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5,14-triol 5-O-ß-D-glucopyranosyl-(1″ → 2')-ß-D-glucopyranoside (2), (-)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5,14-triol 5,14-di-O-ß-D-glucopyranoside (3), (-)-(5S,6E)-tetradeca-6-en-8,10-diyn-1,5,14-triol 5-O-ß-D-glucopyranoside (4), (-)-(5S,6E,12E)-tetradeca-6,12-dien-8,10-diyn-1,5-diol 5-O-ß-D-glucopyranosyl-(1″ → 2')-ß-D-glucopyranoside (5), (-)-(6S,4E,12E)-tetradeca-4,12-dien-8,10-diyn-1,6-diol 6-O-ß-D-glucopyranosyl-(1″ → 2')-ß-D-glucopyranoside (6), and (-)-(5S,6E)-tetradeca-6-en-1,5-epoxy-8,10-diyn-14-ol 14-O-ß-D-glucopyranosyl-(1″ → 2')-ß-D-glucopyranoside (7), respectively. The absolute configurations of 1-7 were assigned by enzymatic hydrolysis followed by isolation of glucose and aglycones (1a and 4a-7a), and subsequent comparison of specific rotation, TLC, and (1)H NMR data of the glucose with an authentic sugar sample and application of modified Mosher's method based on the MPA determination rule of Δδ(RS) values for 1a and 4a, and Δδ(S) values for 6a. The configuration of 7 was assigned by electronic circular dichroism calculations based on the quantum-mechanical time-dependent density functional theory.

4-Hydroxybenzyl-substituted glutathione derivatives from Gastrodia elata.

Seven new 4-hydroxybenzyl-substituted glutathione derivatives (2-8), together with a known analogue (1), were isolated from the aqueous extract of Gastrodia elata Blume rhizomes. Their structures were determined by using spectroscopic and chemical methods. The absolute configurations of 1-8 were assigned by using Marfey's method, combined with comparing the NMR and CD spectroscopic data of sulfoxide moieties in 3-6 with those of S-(4-hydroxybenzyl)cysteine sulfoxide stereoisomers (9-12) synthesized as authentic samples. The configurations of 9-12 were confirmed by electronic CD calculations based on the quantum-mechanical time-dependent density functional theory. Furthermore, the structures of 1, 3, 5, 7, and 8 were verified by synthesis. Compound 3 was active against serum deprivation-induced PC12 cell damage and synthetic 9-14 exhibited activity against Fe(2+)-cysteine induced rat liver microsomal lipid peroxidation.

Aromatic acid derivatives from the lateral roots of Aconitum carmichaelii.

Seven new aromatic acid derivatives (1-7), together with five known analogs, were isolated from the lateral roots of Aconitum carmichaelii. Structures of the new compounds were determined by spectroscopic and chemical methods as 4-methyl ( - )-(R)-hydroxyeucomate (1), 4-butyl ( - )-(R)-hydroxyeucomate (2), 4-butyl-1-methyl (+)-(R)-2-O-(4'-hydroxy-3'-methoxybenzoyl)malate (3), 1-butyl-4-methyl (+)-(R)-2-O-(4'-hydroxy-3'-methoxybenzoyl)malate (4), dimethyl (+)-(R)-2-O-(4'-hydroxy-3'-methoxybenzoyl)malate (5), dimethyl (+)-(R)-2-O-(4'-hydroxybenzoyl)malate (6), and methyl ( ± )-3-(4'-hydroxy-3'-methoxyphenyl)-3-sulfopropionate (7), respectively. Compounds 1 and 2 are 2-benzylmalates (eucomate derivatives), 3-6 belong to 2-O-benzoylmalates, and 7 is a rare phenylpropionate containing a sulfonic acid group. The absolute configurations of eucomate derivatives were confirmed by X-ray crystallographic analysis of 4-methyl eucomate (11).

[Chemical constituents from Litsea greenmaniana].

A new compound (1), together with ten known compounds (2-11), have been isolated from the branch of Litsea greenmaniana by using various chromatographic techniques. Their structures were identified by spectroscopic data analysis as N-trans-3, 4-methylenecinnamoyl-3-methoxytyramine (1), N-trans-feruloyltyramine (2), N-cis-feruloyltyramine (3), (+)-sesamin (4), (+)-pinoresinol(5), cinnamophilin (6), dihydrodehydrodiconiferyl alcohol (7), benzoic acid (8), 4-hydroxy ethylbenzoate (9), p-hydroxybenzaldehyde(10), and 4-hydroxy-3-methoxy-benzyl alcohol (11). Compound 1 was a new compound, and compounds 2-11 were obtained from this plant for the first time.