Possible pharmaceutical applications can be developed from naturally occurring phenanthroindolizidine and phenanthroquinolizidine alkaloids.

Naturally occurring phenanthroindolizidine and phenanthroquinolizidine alkaloids (PIAs and PQAs) are two small groups of herbal metabolites sharing a similar pentacyclic structure with a highly oxygenated phenanthrene moiety fused with a saturated or an unsaturated N-heterocycle (indolizidine/quinolizidine moieties). Natural PIAs and PQAs only could be obtained from finite plant families (such as Asclepiadaceae, Lauraceae and Urticaceae families, etc.). Up to date, more than one hundred natural PIAs, while only nine natural PQAs had been described. PIA and PQA analogues have been applied to the development of potent anticancer agents all along because of their excellent cytotoxic activity. However, in the last two decades, other great biological properties, such as anti-inflammatory and antiviral activities were revealed successively by different pharmacological assays. Especially because of their potent antiviral activity against coronavirus (TGEV, SARS CoV and MHV) and tobacco mosaic virus, PIA and PQA analogues have attracted much pharmaceutical attention again, some of them have been used to present interesting targets for total or semi synthesis, and structure-activity relationship (SAR) study for the development of antiviral agents. In this review, natural PIA and PQA analogues obtained in the last two decades with their herbal origins, key spectroscopic characteristics for structural identification, biological activity with possible SARs and application prospects were systematically summarized. We hope this paper can stimulate further investigations on PIA and PQA analogues as an important source for potential drug discovery.

Paulownia C-geranylated flavonoids: their structural variety, biological activity and application prospects.

Paulownia species, especially their flowers and fruits, are traditionally used in Chinese herbal medicines for the treatment of infectious diseases. C-geranylated flavonoids were found to be the major special metabolites in Paulownia flowers and fruits, and 76 C-geranylated flavonoids had been isolated and characterized thus far. Structural variations in Paulownia C-geranylated flavonoids are mainly due to the complicated structural modifications in their geranyl substituents. These natural compounds have attracted much attention because of their various biological activities, including antioxidation, anti-inflammation, cytotoxic activity and various enzymatic inhibitions, etc. Among them, diplacone, a major Paulownia component, was considered to have promise for applications in medicine. This paper summarizes the information from current publications on Paulownia C-geranylated flavonoids, with a focus on their structural variety, key spectroscopic characteristics, biological activity with structure-activity relationships and application prospects. We hope that this paper will stimulate further investigations of Paulownia species and this kind of natural product.

[Study on Chemical Constituents of Strychnos nux-vomica].

Objective: To isolate and identify the chemical constituents from the seeds of Strychnos nux-vomica. Methods: Chromatographic separation techniques such as silica gel chromatography,ODS chromatography and Sephadex LH-20 chromatography were used for the isolation and purification. The structures of the chemical constituents were identified on the basis of mass spectrometry,NMR spectroscopy and so on. Results: 16 compounds were isolated and their structures were identified as: α-amyrin( 1), vomicine( 2), stearic acid( 3), ß-sitosterol( 4),vanillin( 5), ethyl gallate( 6),methyl gallate( 7),novacine( 8),strychnine( 9), daucosterol( 10),brucine chloromethochloride( 11),loganic acid( 12),strychnine chloromethochloride( 13),brucine( 14),geniposide( 15) and loganin( 16). Conclusion: Compounds 3,6,7 and 15 are isolated from this genus for the first time.

New geranylated flavanones from the fruits of Paulownia catalpifolia Gong Tong with their anti-proliferative activity on lung cancer cells A549.

Three new geranylated flavanones, named as paucatalinone A (1), B (2), and isopaucatalinone B (3), were isolated from the fruits of Paulownia catalpifolia Gong Tong (Scrophulariaceae). Their structures were well determined by means of IR, MS, 1D and 2D NMR, and CD techniques. Paucatalinone A (1) is the first sample as a dimeric geranylated flavanone derivative isolated from natural products. Paucatalinone A (1) displayed good antiproliferative effects on human lung cancer cells A549 and resulted in a clear increase of the percentage of cells in G1 phase and a decrease in the percentage of cells in S and G2/M phases in comparison with control cells.

[Chemical Constituents of Paulownia tomentosa Fruits].

OBJECTIVE: To investigate the chemical constituents from the fruits of Paulownia tomentosa. METHODS: The compounds were isolated and purified by column chromatography and their structures were identified on the basis of physicochemical properties and spectral analyses. RESULTS: Seven compounds were isolated and their structures were identified as ursolic acid (1), sesamin(2),2α,3α, 19a-trihydroxyurs-12-en-28-oic acid(3), luteolin(4), tricin-7-O-ß-D-glucoside(5),3',4',5,7-tetrahydroxy-6-[7-hydroxy-3,7-dimethyl-2(E)-octenyl] flavanone(6) and stigmasterol(7). CONCLUSION: Compounds 3, 5 and 7 are isolated from Paulownia genus for the first time. Compound 2 is isolated from Paulownia tomentosa for the first time.

[Chemical constituents from root bark of Dictamnus dasycarpus].

OBJECTIVE: To isolate and identify the chemical constituents from the root bark of Dictamnus dasycarpus. METHODS: Silica gel, Sephadex LH-20, ODS and PTLC were employed for the isolation and purification of chemical constituents. The structures were identified on the basis of spectral data and physicochemical examination. RESULTS: Thirteen compounds were isolated and identified as follows: rutaevin (1), obacunone (2), fraxinellone (3), limonin (4), dictamnine (5), beta-sitosterol (6), 5-hydroxylmethylfuraldehyde (7), daucosterol (8), 3beta-hydroxy-cholesta-5-ene (9), fraxinellonone (10), rutin (11), quercetin (12) and scopoletin (13). CONCLUSION: Compounds 7 and 9 are isolated from this genus for the first time.

Paucatalinone A from Paulownia Catalpifolia Gong Tong Elicits mitochondrial-mediated cancer cell death to combat osteosarcoma.

As the global cancer burden escalates, the search for alternative therapies becomes increasingly vital. Natural products, particularly plant-derived compounds, have emerged as promising alternatives to conventional cancer treatments due to their diverse bioactivities and favorable biosafety profiles. Here, we investigate Paucatalinone A, a newly discovered geranylated flavanone derived from the fruit of Paulownia Catalpifolia Gong Tong, notable for its significant anti-cancer properties. We revealed the capability of Paucatalinone A to induce apoptosis in osteosarcoma cells and deciphered its underlying mechanisms. Our findings demonstrate that Paucatalinone A substantially augments apoptosis, inhibits cell proliferation, and demonstrates a pronounced anti-tumor effect in a murine model of osteosarcoma. Mechanistically, Paucatalinone A disrupts calcium homeostasis and exacerbates intracellular reactive oxygen species accumulation, leading to mitochondrial impairment, cytoskeletal collapse, and caspase-dependent apoptotic cell death. This study underscores the potential of Paucatalinone A in initiating apoptosis in cancer cells and highlights the therapeutic efficacy of plant-derived agents in treating osteosarcoma, offering a viable approach for managing other intractable cancers.

New cyclic C-geranylflavanones isolated from Paulownia fortunei fruits with their anti-proliferative effects on three cancer cell lines.

Seven new C-geranylated flavanones, fortunones F - L (1-7), were isolated from the fresh mature fruits of Paulownia fortunei (Seem.) Hemsl. Their structures were determined by extensive spectroscopic data interpretation (UV, IR, HRMS, NMR, and CD). These new isolated compounds were all with a cyclic side chain modified from the geranyl group. Among them, compounds 1-3 all possessed a dicyclic geranyl modification, which was described firstly for Paulownia C-geranylated flavonoids. All the isolated compounds were subjected to the cytotoxic assay on human lung cancer cell A549, mouse prostate cancer cell RM1 and human bladder cancer cell T24, respectively. Results indicated A549 cell line was more sensitive to C-geranylated flavanones than the other two cancer cell lines and compounds 1, 7 and 8 exhibited potential anti-tumor effects (IC50 ˂ 10 µM). Further research revealed the effective C-geranylated flavanones could exert their anti-proliferative activity on A549 cells by inducing apoptosis and blocking cells in G1 phase.

[Study on chemical constituents from flowers of Ailanthus altissima].

OBJECTIVE: To isolate and identify the chemical constituents from the flowers of Ailanthus altissima. METHODS: Macroporous adsorptive resins (DM130), Silica gel, Sephadex LH-20, ODS were employed for the isolation and purification of chemical constituents. The structures were identified on the basis of spectral data and physicochemical examination. RESULTS: Eight compounds were isolated and identified as follows: brevifolin (1), brevifolin carboxylic acid (2), methyl brevifolin carboxylate (3), ellagic acid (4), diethyl-2,2',3,3',4,4'- hexahydroxybiphenyl-6,6'-dicarboxylate (5), rutin (6), gallic acid (7), ethyl gallate (8). CONCLUSION: Compounds 1 -5 are isolated from this genus for the first time.

[Chemical constituents of Neoalsomitra integrifoliola].

OBJECTIVE: To study the chemical constituents of the n-BuOH fraction of 95% ethanolic extract of leaves of Neoalsomitra integrifoliola. METHOD: The compounds were isolated with kinds of column chromatography. The structures were determined by MS and NMR spectroscopic techniques. RESULT: Eight compounds were isolated from the n-BuOH fraction of 95% ethanolic extract and their structures were identified as 2-phenylethyl rutinoside (1), rutin (2), kaempferol-3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (3), isorhamnetin-3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (4), methyl chlorogenate (5), guanosine (6), adenosine (7), myo-inositol (8), respectively. CONCLUSION: All compounds were isolated from this genus for the first time.

Dimeric prenylated C6-C3 compounds from the stem bark of Illicium oligandrum.

Three new dimeric prenylated C6-C3 compounds, namely, illicidiones A (1), B (2), and C (3), were isolated from the stem bark of Illicium oligandrum. The structure and absolute configuration of these compounds were determined by extensive spectroscopic and chemical analyses, including NMR, modified Mosher method, and single-crystal X-ray study. Compounds 1-3 exhibited weak anti-inflammatory activities.

Rearranged prenylated C6-C3 compounds and a highly oxygenated seco-prezizaane-type sesquiterpene from the stem bark of Illicium oligandrum.

Three new rearranged prenylated C(6)-C(3) compounds, named illioliganones A, B, and C (1-3), and a new highly oxygenated seco-prezizaane-type sesquiterpene, oligandriortholactone (7), together with three known prenylated C(6)-C(3) compounds (4-6) and a known sesquiterpene lactone (8), have been isolated from the stem bark of Illicium oligandrum. The structures of 1-3 and 7 were elucidated by spectroscopic methods including 1D and 2D NMR, HRMS, and CD experiments. The absolute configuration of the 11,12-diol moiety in 2 and 3 was determined on the basis of observing the induced circular dichroism after addition of Mo(2)(OAc)(4) in DMSO solution. The anti-inflammatory and cytotoxic activities of 1-8 were evaluated.

Undescribed C-geranylflavonoids isolated from the fruit peel of Paulownia catalpifolia T. Gong ex D.Y. Hong with their protection on human umbilical vein endothelial cells injury induced by hydrogen peroxide.

Six undescribed C-geranylated flavonoids, including five C-geranylflavanones named as paucatalinones F - J, one C-geranylflavonol named as paucatalinone K, along with seven known geranylated flavanones, were isolated from the fruit peel of Paulownia catalpifolia T. Gong ex D.Y. Hong. Their structures were elucidated distinctly according to their UV, IR, MS, NMR, and CD data. Among them, two compounds were substituted with unusual modified geranyl groups, namely paucatalinone F with an oxygenated cyclogeranyl substituent and paucatalinone H with a terminal pyranoid geranyl substituent. Furthermore, the protective effects on human umbilical vein endothelial cells (HUVECs) injury induced by H2O2 were evaluated, and paucatalinone F showed the most potential activity. The bioactive results suggested that the geranyl substituent may be an important factor for restraining oxidative HUVECs damage and Paulownia C-geranylated flavonoids might have the potential for preventing cardiovascular complications.

Nine novel C-21 steroidal glycosides substituted with orthoacetate from Dregea sinensis var. corrugata.

Nine novel steroidal glycosides substituted with the orthoacetate groups, compounds 1-5 based on the aglycon of 12-O-acetyl-20-O-benzoyl-dihydrosarcostin 8,14,18-orthoacetate and compounds 6-9 based on the aglycon of 12-O-acetyl-20-O-benzoyl-dihydrosarcostin 14,17,18-orthoacetate, were isolated from Dregea sinensis var. corrugata. Their structures were deduced on the basis of chemical and spectral evidences. Compound 1 showed moderate anti-inflammatory activity.

[Water-soluble constituents from roots of Capparis tenera].

OBJECTIVE: To study the chemical constituents of the roots of Capparis tenera. METHOD: The chemical constituents were isolated and repeatedly purified by kinds of column chromatography and the structures were elucidated by the NMR spectra and physicochemical properties. RESULT: Eight compounds were isolated and identified as erigeside C (1), glucosuringic acid (2), vanillic acid 4-O-beta-D-glucoside (3-methoxy 4-glucosyl-benzoic acid) (3), 4-O-beta-D-glucopyranosylbenzoate (4), 3', 5'-dimethoxy- 4-O-beta-D-glucopyranosyl-cinnamic acid (5), tachioside (6), 2, 3-dihydroxy-1-(4-hydroxyl-3, 5-dimethoxyphenyl)-1-propanone (7) and acacetin 7-rutinoside (8). CONCLUSION: Compounds 1-8 were all isolated from this plant for the first time and the compound 8 was isolated from this gene for the first time.

Eight new C-21 steroidal glycosides from Dregea sinensis var. corrugata.

Eight new steroidal glycosides, dresiosides were isolated from the stems of Dregea sinensis var. corrugate and their structures were deduced on the basis of chemical and spectral evidence. The sugar units of dresiosides were determined as deoxysugars after hydrolysis and isolation from natural glycosides. The absolute configurations of deoxysugars were determined as D on the basis of their optical rotation values in comparison with appropriate standards.

Glucosides from the roots of Capparis tenera.

Two new lignan glucosides, compounds 2 and 3, two new 1H-indole-alkaloid glucosides, 5 and 6, as well as two new phenolic glucosides, 7 and 10, were isolated from the roots of Capparis tenera, together with five known compounds. Their structures were characterized by chemical and spectroscopic methods. Most of these isolates were obtained for the first time from Capparidaceae. The antioxidant and anti-inflammatory activities of the new compounds were investigated.

Identification of C-geranylated flavonoids from Paulownia catalpifolia Gong Tong fruits by HPLC-DAD-ESI-MS/MS and their anti-aging effects on 2BS cells induced by H2O2.

The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C (1) and five known C-geranylated flavanones (2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CH2Cl2 extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by H2O2. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone (3) and paucatalinone A (5) were the potent anti-aging agents in the premature senescent 2BS cells induced by H2O2 and the C-geranyl substituent may be an important factor because of its lipophilic character.

Development of Marker-Free Transgenic Potato Tubers Enriched in Caffeoylquinic Acids and Flavonols.

Potato (Solanum tuberosum L.) is a major crop worldwide that meets human economic and nutritional requirements. Potato has several advantages over other crops: easy to cultivate and store, cheap to consume, and rich in a variety of secondary metabolites. In this study, we generated three marker-free transgenic potato lines that expressed the Arabidopsis thaliana flavonol-specific transcriptional activator AtMYB12 driven by the tuber-specific promoter Patatin. Marker-free potato tubers displayed increased amounts of caffeoylquinic acids (CQAs) (3.35-fold increases on average) and flavonols (4.50-fold increase on average). Concentrations of these metabolites were associated with the enhanced expression of genes in the CQA and flavonol biosynthesis pathways. Accumulation of CQAs and flavonols resulted in 2-fold higher antioxidant capacity compared to wild-type potatoes. Tubers from these marker-free transgenic potatoes have therefore improved antioxidant properties.

Ultra-HPLC method for quality and adulterant assessment of steviol glycosides sweeteners - Stevia rebaudiana and stevia products.

Stevia products are advertised as a zero-calorie sweetener. Glucose should not be an intrinsic component of this product, but it has been identified from some of stevia products in a preliminary study. An UHPLC-UV method was developed for the quantitative determination of glucose from stevia products. After stevia products reacted with 1-phenyl-3-methyl-5-pyrazolone (PMP), PMP derivatives were analysed and glucose was found in seven out of 35 products in the range 0.3-91.5% (w/w). Two products, SPR-12 and SPR-27, showed remarkable amounts of glucose at 61.6% and 91.5%, respectively. In addition, an UHPLC-UV-evaporative light-scattering detector (ELSD) method was developed for the quantitative determination of rebaudioside A, stevioside, rebaudioside D, dulcoside A and steviolbioside from Stevia rebaudiana and related products. In a 12 min run, five steviol glycosides were baseline-separated. ELSD and ultraviolet (UV) detections showed comparable results. The LC methods were validated for linearity, repeatability, accuracy, limits of detection (LOD) and limits of quantification (LOQ). For steviol glycosides, the LODs and LOQs were found to be less than 10 and 30 µg ml(-1), respectively. The RSD for intra- and inter-day analyses was less than 2.5%, and the recovery was 90-94%. For PMP derivative of glucose, the LOD and LOQ were 0.01 and 0.05 µg ml(-1), respectively. Repeatability (RSD) was less than 2.6%; recovery was 98.6-101.7%. The methods are useful for the identification, quality assurance, and adulterant assessment of S. rebaudiana and steviol glycosides sweeteners (stevia products).