Two new prenylated 2-arylbenzofurans from roots of Artocarpus heterophyllus and their anti-respiratory burst activities / 中国中药杂志

Two prenylated 2-arylbenzofurans were isolated from roots of Artocarpus heterophyllus, with a combination of various chromatographic approaches, including ODS, MCI, Sephadex LH-20, and semipreparative high performance liquid chromatography(HPLC). They were identified as 5-[6-hydroxy-4-methoxy-5,7-bis(3-methylbut-2-enyl)benzofuran-2-yl]-1,3-benzenediol(1) and 5-[2H,9H-2,2,9,9-tetramethyl-furo[2,3-f]pyrano[2,3-h][1]benzopyran-6-yl]-1,3-benzenediol(2) with spectroscopic methods, such as HR-ESI-MS, IR, 1D NMR, and 2D NMR, and named artoheterins B(1) and C(2), respectively. The anti-respiratory burst activities of the two compounds were evaluated with rat polymorphonuclear neutrophils(PMNs) stimulated by phorbol 12-myristate 13-acetate(PMA). The results showed that 1 and 2 exhibited significant inhibitory effect on respiratory burst of PMNs with IC_(50) values of 0.27 and 1.53 μmol·L~(-1), respectively.

A new bibenzyl derivative from stems of Dendrobium officinale / 中国中药杂志

Eleven compounds were isolated from the 95% ethanol extract of the stems of Dendrobium officinale after water extraction by various modern chromatographic techniques, such as silica gel column chromatography(CC), octadecyl-silica(ODS) CC, Sephadex LH-20 CC, preparative thin layer chromatography(PTLC) and preparative high performance liquid chromatography(PHPLC). According to spectroscopic analyses(MS, 1D-NMR, 2D-NMR) combined with optical rotation data and calculated electronic circular dichroism(ECD), their structures were identified as dendrocandin Y(1), 4,4'-dihydroxybibenzyl(2), 3-hydroxy-4',5-dimethoxybibenzyl(3), 3,3'-dihydroxy-5-methoxybibenzyl(4), 3-hydroxy-3',4',5-trimethoxybibenzyl(5), crepidatin(6), alternariol(7), 4-hydroxy-3-methoxypropiophenone(8), 3-hydroxy-4,5-dimethoxypropiophenone(9), auriculatum A(10) and hyperalcohol(11). Among them, compound 1 was a new bibenzyl derivative; compounds 2 and 7-11 have not been previously reported from Dendrobium plants; compound 6 was reported from D.officinale for the first time. Compounds 3-6 exhibited potent antioxidant activity with IC_(50) values of 3.11-9.05 μmol·L~(-1) in ABTS radical scavenging assay. Compound 4 showed significant inhibitory effect on α-glucosidase, with IC_(50) value of 17.42 μmol·L~(-1), indicating that it boasted hypoglycemic activity.

Bioassay-guided isolation of α-Glucosidase inhibitory constituents from Hypericum sampsonii / 中国天然药物

This study employed the α-glucosidase inhibitory activity model as an anti-diabetic assay and implemented a bioactivity-guided isolation strategy to identify novel natural compounds with potential therapeutic properties. Hypericum sampsoniiwas investigated, leading to the isolation of two highly modified seco-polycyclic polyprenylated acylphloroglucinols (PPAPs) (1 and 2), eight phenolic derivatives (3-10), and four terpene derivatives (11-14). The structures of compounds 1 and 2, featuring an unprecedented octahydro-2H-chromen-2-one ring system, were fully characterized using extensive spectroscopic data and quantum chemistry calculations. Six compounds (1, 5-7, 9, and 14) exhibited potential inhibitory effects against α-glucosidase, with IC50 values ranging from 0.050 ± 0.0016 to 366.70 ± 11.08 μg·mL-1. Notably, compound 5 (0.050 ± 0.0016 μg·mL-1) was identified as the most potential α-glucosidase inhibitor, with an inhibitory effect about 6900 times stronger than the positive control, acarbose (IC50 = 346.63 ± 15.65 μg·mL-1). A docking study was conducted to predict molecular interactions between two compounds (1 and 5) and α-glucosidase, and the hypothetical biosynthetic pathways of the two unprecedented seco-PPAPs were proposed.

Advances in heterologous expression, structural elucidation and molecular modification of pullulanase / 生物工程学报

Starch is composed of glucose units linked by α-1, 4-glucoside bond and α-1, 6-glucoside bond. It is the main component of foods and the primary raw material for starch processing industry. Pullulanase can effectively hydrolyze the α-1, 6-glucoside bond in starch molecules. Combined with other starch processing enzymes, it can effectively improve the starch utilization rate. Therefore, it has been widely used in the starch processing industry. This paper summarized the screening of pullulanase-producing strain and its encoding genes. In addition, the effects of expression elements and fermentation conditions on the production of pullulanase were summarized. Moreover, the progress in crystal structure elucidation and molecular modification of pullulanase was discussed. Lastly, future perspectives on pullulanase research were proposed.

Discovery of alkaloids from the leaves of Isatis indigotica Fortune with neuroprotective activity / 中国天然药物

Seven alkaloids including five undescribed ones (1a/1b, 2, 3 and 5) were obtained from the leaves of Isatis indigotica Fortune. Their structures were established by extensive spectroscopic analyses. The absolute configurations of compounds 1a, 1b, 3 and 5 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Subsequently, the neuroprotective effects of all the isolates against H

Terpenoids from leaves of Chinese hawthorn / 中国中药杂志

Fifteen compounds were isolated from the 70% EtOH extract of leaves of Chinese hawthorn(Crataegus pinnatifida var. major) by various purification steps, and their structures were determined as 2α,3α,12β,19α,-tetrahydroxyursan-13β,28-olide(1),euscaphic acid(2), tormentic acid(3), ursolic acid(4), pomolic acid(5), corosolic acid(6), maslinic acid(7), linalyl rutinoside(8),(Z)-3-hexenyl β-D-glucoside(9),(3S, 6S)-cis-linalool-3,7-oxide-β-D-glucopyranoside(10), pisumionoside(11), icariside B6(12), byzantionoside B(13),(6R,7E,9R)-9-Hydroxy-4,7-megastigmadien-3-one 9-O-β-D-glucopyranoside(14) and(6S,7E,9R)-6,9-dihydroxy-4,7-megastigmadien-3-one 9-O-β-D-glucopyranoside(15) mainly based on the mass spectrum(MS) and nuclear magnetic resonance(NMR) spectroscopic techniques, of which compound 1 was a new pentacyclic triterpene, and compounds 2, 5, 6, 8, 10, 13 and 15 were isolated form this plant for the first time.

Research on chemical constituents from Artemisia annua Ⅰ / 中国中药杂志

Chemical constituents were isolated and purified from the water extract of Artemisia annua by column chromatography of HP-20 macroporous resin, silica gel, ODS, Sephadex LH-20, HW-40, and semi-preparative RP-HPLC. Their structures were elucidated by physicochemical properties and spectral analyses. As a result, Fifteen compounds were isolated and identified as vitexnegheteroin M(1), sibricose A5(2), securoside A(3), citrusin D(4), annphenone(5), E-melilotoside(6), esculetin(7), scopoletin-7-O-β-D-glucoside(8), eleutheroside B_1(9), chrysosplenol D(10), patuletin-3-O-β-D-glucopyranoside(11), quercetin-7-O-β-D-glucoside(12), rutin(13), apigenin 6,8-di-C-β-D-glucopyranoside(14), isoschaftoside(15), among them, compounds 1-4 were identified from Artemisia for the first time. Additionally, the isolates were evaluated for their inhibitory effects on the production of PGE_2 in LPS-simulated RAW264.7 macrophages. The results showed that compounds 1, 2, 8, and 10-15 could reduce PGE_2 levels, to a certain extent.

Study on the secondary metabolites of grasshopper-derived fungi Arthrinium sp. NF2410 / 中国天然药物

Two new 2-carboxymethyl-3-hexyl-maleic anhydride derivatives, arthrianhydride A (1) and B (2), along with three known compounds 3-5, were isolated from the fermentation broth of a grasshopper-associated fungus Arthrinium sp. NF2410. The structures of new compounds 1 and 2 were determined based on the analysis of the HR-ESI-MS and NMR spectroscopic data. Furthermore, compounds 1 and 2 were evaluated on inhibitory activity against the enzyme SHP2 and both of them showed moderate inhibitory activity against SHP2.

Chemical Constituents of Corydalis impatiens and Their Inhibitory Effect on Proliferation of Hepatoma Cells / 中国实验方剂学杂志

Objective:To systematically investigate the chemical constituents of 90% ethanol extract of Corydalis impatiens，and evaluate their inhibitory effect on cell proliferation in vitro. Method:The chemical constituents were isolated and purified by silica gel，Sephadex LH-20，ODS column chromatography and semi-preparative high performance liquid chromatography （HPLC）.the structures were identified by spectroscopy methods such as NMR and MS，as well as analysis of physicochemical properties and/or comparison with literature data，and the inhibitory activities of 13 compounds on HepG2 and SMMC-7721 cells were measured by methyl thiazolyl tetrazolium （MTT） method. Result:Thirteen known compounds were isolated and identified from 90% ethanol extract of Corydalis impatiens as ethyl-5-hydroxy-2-pyridinecarboxylate（1），coryhumolide（2），3，4-cis-3，4-dihydroxy-β-ionone（3），megastigmane（4），9-hydroxy-4，7-megastigmadien-3-one（5），blumenol A（6），indole-3-carboxy acid（7），1-methyl-[1，2，4]triazolo[4，3-b][1，2，4]triazin-7-one （8），adenine（9），nicotinamide（10），2-hydroxymethyl-5-pyridinol（11），adenosine（12）， and β-daucosterol（13）. Cytotoxicities assay showed that the IC50 value of compound 3 for the hepatic cell line HepG2 was 24.7 μmol·L-1 （positive control drug cisplatin：4.8 μmol·L-1），and IC50 value of compound 4 for the hepatic cell line SMMC-7721 was 13.8 μmol·L-1（positive control drug cisplatin：5.4 μmol·L-1）. Conclusion:Compound 1 was a new natural compound，compounds 3-8 were obtained from genus Corydalis for the first time，and compounds 2，9-12 were isolated from this plant for the first time. Compound 3 exhibited weak inhibitory effect on hepatic cell line HepG2，and compound 4 exhibited moderate inhibitory effect on hepatic cell line SMMC-7721.The other compounds rest of ones exhibited no obvious inhibitory effect on hepatic cell line HepG2 or SMMC-7721.

Two new compounds from rifamycin resistant mutant strain Streptomyces sp. HS-NF-1046R / 药学学报

Using silica gel column chromatography, gel chromatography and HPLC, we isolated secondary metabolites in fermentation broth of a rifamycin resistant mutation strain Streptomyces sp. HS-NF-1046R. Based on spectroscopic data, the chemical structures of three compounds were identified as 3-hydroxyl-2-N-propionyl- anthranilamide (1), 2,3-dihydro-8-hydroxy-2,2-dimethyl quinazolin-4-(1H)-one (2) and 2-aminobenzamide (3). Compounds 1 and 2, as new entities, were evaluated for cytotoxicity against A549, HepG2, HCT-116 and K562 cells using the SRB assay. Compounds 1 and 2 exhibited no cytotoxicity with IC50 over 100 μmol·L-1.

Four new cis-phenylethanoid glycosides from stems of Cistanche deserticola cultured in Tarim desert / 中国中药杂志

In order to clarify the chemical constituents of Cistanche deserticola cultured in Tarim desert, a systematically phytochemical investigation was carried out. The chemical constituents were isolated by column chromatography, such as silica gel, Sephadex LH-20, MCI gel, ODS and semi-preparative HPLC, and their structures were determined on the basis of MS, NMR spectroscopic analysis, and comparison with literature data. Four compounds were isolated from the 85% ethanol extract of the stems of C. cultured in Tarim desert. Their structures were identified as cis-tubuloside (1), cis-cistanoside (2), cis-cistanoside J (3), and cis-isocistanoside C(4). Compounds 1-4 were four new cis-phenylethanoid glycosides. Herein, we firstly report the ¹H, ¹³C-NMR data of the new compounds(1-4) for the first time. This study will provide the scientific evidence for comprehensively analyzing the chemical constituents of C. deserticola cultured in Tarim desert.

Historical story on natural medicinal chemistry: Biosynthesis of natural products / 中草药

Natural products are the main resource of leading compounds and new drugs because of their unique chemical structures and strong bioactivities. Through the primary and secondary metabolic processes, the plants synthesize various types of natural products only using carbon dioxide, water, and enzymes. Some of these structure-specific bioactive compounds have become the hot spots for organic synthetic chemists. To figure out the biosynthesis pathway of natural products is helpful for the artificial synthesis and structure elucidation of natural products; Meanwhile, the principle of biosynthesis, reaction classification, and reaction mechanism also provide inspiration for the research field of organic synthesis. Chemical biology and synthetic biology based on the development and integration of natural product chemistry and molecular biology also promot the birth of new disciplines.

Chemical Constituents from Periplaneta americana / 中国药学杂志

OBJECTIVE: To study the chemical constituents from Periplaneta americana. METHODS: The 95% enthanol extract was isolated and purified by column chromatography on silica gel, Sephadex LH - 20, ODS and semi-PHPLC. All compounds were identified by chemical and spectral analyses. RESULTS: Fourteen compounds were isolated and purified from Periplaneta americana. Their structures were elucidated as salicylic acid (1), benzoic acid (2), phenylacetic acid (3), methyl 4-hydroxyphenylacetate (4), p-hydroxybenzoic acid (5), genistein (6), 3-hydroxybenzoic acid (7), methyl N-(2-hydroxybenzoyl) glycinate (8), 2, 5 -dihydroxybenzoic acid (9), (2-hydroxybenzoyl) glycine (10), uracil (11), cyclo(Val-Ala) (12), N-acetyldopamine (13), and cyclo( L-Pro-L-Tyr) (14), respectively. CONCLUSION: Compounds 2, 4, 7 - 10, 12 and 14 are obtained from this genus for the first time.

Historical story on natural medicinal chemistry: The most preeminent natural organic chemist of 20th century-Robert Burns Woodward / 中草药

Robert Burns Woodward was a well-known natural organic chemist. This paper reviewed the work and his contribution to the development of natural product chemistry and total synthesis of natural products including spectroscopic methods such as UV, IR, and NMR, the Octant Rule, structure elucidation and total synthesis of natural products, theory study, biogenesis, et al. This is one of the series papers about historical story on natural medicinal chemistry, which was dedicated to Robert Burns Woodward on the occasion of his 100th birthday.

Nine compounds from the root bark ofand their anti-inflammatory activitieslammatory activitiesretain-->

Two new compounds, named lyciumlignan D () and lyciumphenyl propanoid A (), along with seven known compounds, were isolated from the root bark of. Their structures were elucidated using spectroscopic data (UV, IR, HR-ESI-MS, 1D and 2D NMR, CD), as well as by comparison with those of the literature. Compounds-were isolated from this genus for the first time. In theassay, compounds,, andexhibited stronger anti-inflammatory effects than the positive control curcumin at a concentration of 10 μmol/L.

Anti-inflammatory iridoids from the stems of Cistanche deserticola cultured in Tarim Desert / 中国天然药物

In order to determine the chemical constituents of Cistanche deserticola cultured in Tarim desert, a systematically phytochemical investigation was carried out. The constituents were isolated by silica gel, Sephadex LH-20, MCI gel, ODS column chromatography, and semi-preparative HPLC. Their structures were determined on the basis of MS and NMR spectroscopic analyses, by chemical methods, and/or comparison with literature data. The anti-inflammatory activities of the isolates were evaluated for their inhibitory effects on the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 mouse microglial cells. Nine iridoids were isolated and identified as cistadesertoside A (1), cistanin (2), cistachlorin (3), 6-deoxycatalpol (4), gluroside (5), kankanoside A (6), ajugol (7), bartsioside (8), and 8-epi-loganic acid (9). Compound 9 exhibited potent inhibition on the NO production with an IC50 value being 5.2 μmol·L(-1), comparable to the positive control quercetin (4.3 μmol·L(-1)). Compound 1 was a new iridoid, and compounds 5, 6, and 8 were isolated from this species for the first time.

A new tetrahydrofuran lignan from Peperomia blanda / 国际药学研究杂志

Objective To investigate the chemical constituents of Peperomia blanda. Methods Guided by HPLC detection, integrated methods including vacuum liquid chromatography (VLC), ODS and semi-preparative RP-HPLC were used for separation. The structure was determined by spectral analyses including ESI-MS, 1D NMR, 2D NMR and ECD spectra. Results Four compounds were isolated and identified as (7S,7’S,8R,8 ’R)-7-(5-methoxy-3,4-methylenedioxyphenyl)-7-(4-hydroxy-3,5-dimethoxy-phenyl)-8, 8-dihydroxymethyltetrahydrofuran (1), 7, 8-trans-8,8-trans-7,8-cis-7, 7-(4-hydroxy-3,5-dimethoxy phenyl)-8,8-di-acetoxymethyltetrahydrofuran (2), (+)-(7S, 7S, 8R, 8R)-4, 4-dihydroxy-3, 3, 5, 5-tetramethoxy-7, 9, 7, 9-diepoxylignane (3), and (6R, 7E, 9R)-9-hydroxy-4, 7-megastigmadien-3-one (4). Conclusion Compound 1 is a new tetrahydrofuran lignan, compounds 2-4 were isolated from P. blanda for the first time.

Lignans from cultivated Gynura nepalensis / 中国中药杂志

Taking application of some isolation and purification technologies, including solvent extraction, rude solvent isolation, column chromatographies on silica gel and Sephadex LH-20 , and preparative HPLC , 4 compounds were obtained from Gynura nepalensis cultivated in a suburban area of Beijing. Their structures were identified by spectroscopic methods in conjunction with comparison of the NMR data with literature values as 7S,8R-9'-O-ethyl-dehydrodiconiferyl-9-acetate (1), 9'-O-ethyl-dehydrodiconiferyl alcohol (2), dehydrodiconiferyl-9,9'-diacetate(3), and (+)-medioresinol(4), respectively. 1 is a new 2,3-dihydrobenzofuran-8,3'-neolignane type compound, and 2-4 were isolated from G.nepalensis for the first time. The complete assignment of the 1H- and 13C-NMR spectroscopic data of the four compounds recorded in DMSO-d6 was achieved.

A new tetrahydrofuran lignan from Peperomia blanda / 国际药学研究杂志

Objective To investigate the chemical constituents of Peperomia blanda. Methods Guided by HPLC detec?tion,integrated methods including vacuum liquid chromatography(VLC),ODS and semi-preparative RP-HPLC were used for separa?tion. The structure was determined by spectral analyses including ESI-MS,1D NMR,2D NMR and ECD spectra. Results Four com?pounds were isolated and identified as(7S,7′S,8R,8′R)-7-(5-methoxy-3,4-methylenedioxyphenyl)-7′-(4-hydroxy-3,5-dimethoxy?phenyl)-8,8′-dihydroxymethyltetrahydrofuran(1),7,8-trans-8,8′-trans-7′,8′-cis-7,7′-(4-hydroxy-3,5-dimethoxy phenyl)-8,8′-di?acetoxymethyltetrahydrofuran(2),(+)-(7S,7′S,8R,8′R)-4,4′-dihydroxy-3,3′,5,5′-tetramethoxy-7,9′,7′,9-diepoxylignane(3), and(6R,7E,9R)-9-hydroxy-4,7-megastigmadien-3-one(4). Conclusion Compound 1 is a new tetrahydrofuran lignan,compounds 2-4 were isolated from P. blanda for the first time.

Cytotoxic compounds from the leaves of Garcinia cowa Roxb.

The aims of this study was to isolate compounds from the leaves of methanol extract of Garcinia cowa and to evaluated their cytotoxic activity against breast (MCF-7) and lung (H-460) cell lines. The dichloromethane fraction was separated by successive silica gel column chromatography to give three compounds. Based on spectroscopic comparison with those of the literature these compounds were elucidated as methyl 2,4,6- trihydroxy-3-(3-methylbut-2-enyl)benzoate (1), garcinisidone-A (2) and methyl 4,6dihydroxy-2-(4-methoxy-5- (3-methylbut-2-enyl)-3,6-dioxocylohexa-1,4-dienyloxy)-3-(3-methylbut-2-enyl)benzoate (3). Compound 1, 2 and 3 had IC50 value of 21.0 ± 10.2 μM, 21.2 ±8.4 μM and 17.2 ± 6.2μM against MCF-7, while only compound (2) was found to be in active against H-460 with IC50 value of 18.1 ± 6.7 μM. Conclusion: The results indicate that G. cowa leaves could be important sources of natural cytotoxic compounds and only compound (2) had activity against H-460 cell lines.