Insecticidal and α-glucosidase inhibitory activities of chemical constituents from Viburnum fordiae Hance

The ethanolic extract of the stems of Viburnum fordiae Hance showed insecticidal and α-glucosidase inhibitory activities and then was fractionated by bioactivity-guided fractionation to obtain a rare C₁₃-norisoprenoid (1), together with a new phenolic glycoside (2), and seven known compounds, alangionoside C (3), pisumionoside (4), koaburaside (5), 3,5-dimethoxy-benzyl alcohol 4-O-β-d-glucopyranoside (6), 3,4,5-trimethoxybenzyl-β-d-glucopyranoside (7), arbutin (8), and salidroside (9). The previously undescribed compounds were elucidated as (3R,9R)-3-hydroxy-7,8-didehydro-β-ionyl 9-O-α-d-arabinopyranosyl-(1→6)-β-d-glucopyranoside (1) and 2-(4-O-β-d-glucopyranosyl)syringylpropane-1,3-diol (2) by spectroscopic data (¹H and ¹³C NMR, HSQC, HMBC, ¹H-¹H COSY, HSQC-TOCSY, HRESIMS, IR and ORD) and chemical methods. Compound 1 showed potent insecticidal effect against Mythimna separata with LD₅₀ value of 140 μg g^?1. Compounds 2, 5, 6, 8 and 9 showed varying α-glucosidase inhibitory activity with IC₅₀ values ranging from 148.2 to 230.9 μM.     

A new anthraquinone glycoside from Rhamnus nakaharai and anti-tyrosinase effect of 6-methoxysorigenin

In continual study on the heartwood of Rhamnus nakaharai, a new alaternin-8-O-glucoside, namely 1,2,6,8-tetrahydroxy-3-methylanthraquinone-8-O-β-glucopyranoside (1), together with some known compounds were further isolated and characterised by 1-D, 2-D NMR and other spectral evidences. The free radical scavenging and antityrosinase activities of the isolates, including alaternin (1a), emodin (2a), emodin-8-O-β-glucopyranoside (2), 6-methoxysorigenin-8-O-β-glucopyranoside (3) and 6-methoxysorigenin (3a) were tested. Alaternin (1a) exhibited to be mild DPPH radical scavenger with half as potent as vitamin C, while both alaternin (1a) and emodin-8-O-β-glucopyranoside (2) exhibited stronger SOD-like activity than that of BHA. 6-Methoxysorigenin (3a), a reported potential antioxidant, and its 8-O-glucoside (3) both performed significant inhibitory effect on mushroom tyrosinase with about twice as potent as kojic acid, the positive control.     

Xanthones isolated from Gentianella acuta and their protective effects against H2O2-induced myocardial cell injury

In the present study, two new xanthones, (5′S,8′S)-1,3,5,8-tetrahydroxyxanthone(7→2′)-1,3,5,8-tetrahydroxy-5′,6′,7′,8′-tetrahydroxanthone (1), 5-hydroxy-3,4,6-trimethoxyxanthone-1-O-β-D-glucopyranoside (2), and eight known xanthones (3–10) were isolated from the whole plants of Gentianella acuta. Their structures were identified by the spectroscopic analyses (HR-ESI-MS, and 1D and 2D NMR). Meanwhile, cell-protective effects against H₂O₂-induced H9c2 cardiomyocyte injury and cytotoxic activities of compounds 1–10 were also determined.     

A bioactive cycloartane triterpene from Garcinia hombroniana

The dichloromethane bark extract of Garcinia hombroniana yielded one new cycloartane triterpene; (22Z,24E)-3β-hydroxycycloart-14,22,24-trien-26-oic acid (1) together with five known compounds: garcihombronane G (2), garcihombronane J (3), 3β acetoxy-9α-hydroxy-17,14-friedolanostan-14,24-dien-26-oic acid (4), (22Z, 24E)-3β, 9α-dihydroxy-17,14-friedolanostan-14,22,24-trien-26-oic acid (5) and 3β, 23α-dihydroxy-17,14-friedolanostan-8,14,24-trien-26-oic acid (6). Their structures were established by the spectral techniques of NMR and ESI-MS. These compounds together with some previously isolated compounds; garcihombronane B (7), garcihombronane D (8) 2,3’,4,5’-tetrahydroxy-6-methoxybenzophenone (9), volkensiflavone (10), 4’’-O-methyll-volkensiflavone (11), volkensiflavone-7-O-glucopyranoside (12), volkensiflavone-7-O-rhamnopyranoside (13), Morelloflavone (14), 3’’-O-methyl-morelloflavone (15) and morelloflavone-7-O-glucopyranoside (16) were evaluated for cholinesterase enzymes inhibitory activities using acetylcholinesterase and butyrylcholinesterase. In these activities, compounds 1–9 showed good dual inhibition on both the enzymes while compounds 10–16 did not reasonably contribute to both the cholinesterases inhibitory effects.     

Selective Benzoylation of 1-(β-D-Xylopyranosyl)-3,5-dimethylpyrazole

Abstract

Selective benzoylation of l-(β-d-xylopyranosyl)-3,5-dimethylpyrazole (1) has been performed to give 2,3,4-tri- (2), 3,4-di- (3), 2,4-di- (4), 3- (5) and 4-benzoate (6). The O-acetyl derivatives of compounds 3 and 4 (7, 8), di-O-acetyl of 5 and 6 (9, 10) and O-methanesulphonyl of 3 and 4 (11, 12) have been obtained. The relative reactivity of the hydroxyl groups of 1 was HO-4 ≥ HO-3 ? HO-2. The analysis of ¹ H NMR and ¹³C NMR spectra of 1-12 is presented.     

短柄雪胆中的三萜葫芦素及其皂苷

从短柄雪胆的块根中分离得到了14个三萜葫芦素类化合物. 经波谱分析及化学方法鉴定了它们的结构, 其中有新化合物5个, 分别命名为短柄雪胆苷A～E (1～5), 以及肉花雪胆苷元A (6), 藤三七雪胆苷R8 (7), 肉花雪胆苷I (8), 肉花雪胆苷II (9), 肉花雪胆苷III (10), 雪胆甲素(11), 雪胆乙素(12), 雪胆甲素苷(13), 藤三七雪胆苷R1 (14)等9个已知化合物. 6是首次从自然界中得到的化合物.     

A new arbutin derivative from the leaves of Vaccinium dunalianum wight

A new arbutin derivative, namely dunalianosides J (1), along with six known compounds, arbutin (2), robustaside A (3), 6′-O-caffeoylarbutin (4), dunalianoside D (5), kaempferol 3-O-β-D-glucopyranoside (6) and kaempferol 3-O-β-D-sambubioside (7) were isolated from the leaves of Vaccinium dunalianum Wight (Ericaceae). The structure of 1 was elucidated by extensive 1D and 2D NMR, HR-MS and CD spectroscopic analyses. In which, kaempferol 3-O-β-D-sambubioside (7) was isolated from the genus Vaccinium for the first time.     

A new alkylbenzoquinone from Embelia rowlandii Gilg. (Myrsinaceae)

A new alkylbenzoquinone named embeliquinone (1) together with five known compounds, lupeol (2), 3-O-[6′-O-palmitoyl-β-d-glucosyl]-spinasta-7,22(23)-diene (3), quercetin (4), (2S,3S,4R,8E)-2-[(2′R)-2′-hydroxy-heneicosanoylamino]-heneicosane-1,3,4-triol-8-ene (5), and β-sitosterol-3-O-β-d-glucopyranoside (6) were isolated from the MeOH leaf extract of Embelia rowlandii by using repeated open column chromatography techniques. The structure of the new compound was characterized by analyses of 1D- and 2D-NMR, and MS data. Embeliquinone (1) had moderate anti-cell proliferation activity against A549 cell line with the IC₅₀ value of 21.8 μM. In addition, 1 exhibited weak antibacterial activities against Klebsiella pneumoniae and Staphylococcus aureus with an MIC value of 206.0 μM in both cases.     

A new glucosidic phthalide from Helichrysum microphyllum subsp. tyrrhenicum from La Maddalena Island (Sardinia,Italy)

In this study, we reported the analysis of the medium polarity fraction obtained from an accession of Helichrysum microphyllum subsp. tyrrhenicum from La Maddalena Island. Besides several compounds already evidenced in this species and related genera, i.e. micropyrone (1), arzanol (2), helipyrone (3), acetyl-bitalin derivatives (4, 5), gnaphaliol (6), caffeic acid (7), ursolic acid (8), 7-O-β-(d-glucopyranosyl)-5-methoxy-1(3H)-isobenzofuranone (9), gnaphaliol-9-O-β-d-glucopyranoside (11) and gnaphaliol-3-O-β-d-glucopyranoside (12), the presence of a new glycosidic phthalide, 6-O-β-(d-glucopyranosyl)-4-methoxy-1(3H)-benzofuranone (10), was evidenced for the first time, which resulted in a structural isomer of compound (9). The occurrence of this new benzofuranone derivative is an additional evidence of the deep intraspecific variability expressed by this species, which was also stated for the non-volatile components, and may be a distinctive trait of the population growing on La Maddalena Island.     

Chemical constituents from Gueldenstaedtia verna and their anti-inflammatory activity

A new triterpenoid glycoside (1) and 15 known compounds (2–16) were isolated from the whole plants of Gueldenstaedtia verna. The new compound (1) was identified as complogenin 22-O-β-d-glucopyranoside by extensive spectroscopic techniques including 1D (¹H and ¹³C) and 2D NMR experiments (HSQC, HMBC and NOESY), HR-DART-MS and chemical methods. Most of the isolates were evaluated for their inhibitory activities on LPS-induced NO production in RAW 264.7 cells. The inhibitory effects of the active compounds, sulphuretin (8) and (22E,24S)-5α,8α-epidioxy-24-methyl-cholesta-6,9(11),22-trien-3β-ol (13), on the production of pro-inflammatory mediators (including IL-6, IL1β and PGE₂) were further estimated in vitro by ELISA in RAW 264.7 macrophages.     

Isolation,structural elucidation and cytotoxicity evaluation of a new pentahydroxy-pimarane diterpenoid along with other chemical constituents from Aerva lanata

Aervalanata possesses various useful medicinal and pharmaceutical activities. Phytochemical investigation of the plant has now led to the isolation of a new 2α,3α,15,16,19-pentahydroxy pimar-8(14)-ene diterpenoid (1) together with 12 other known compounds identified as β-sitosterol (2), β-sitosterol-3-O-β-D-glucoside (3), canthin-6-one (4), 10-hydroxycanthin-6-one (aervine, 5), 10-methoxycanthin-6-one (methylaervine, 6), β-carboline-1-propionic acid (7), 1-O-β-D-glucopyranosyl-(2S,3R,8E)-2-[(2′R)-2-hydroxylpalmitoylamino]-8-octadecene-1,3-diol (8), 1-O-(β-D-glucopyranosyl)-(2S,3S,4R,8Z)-2-[(2′R)-2′-hydroxytetracosanoylamino]-8(Z)-octadene-1,3,4-triol (9), (2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (10), 6′-O-(4″-hydroxy-trans-cinnamoyl)-kaempferol-3-O-β-D-glucopyranoside (tribuloside, 11), 3-cinnamoyltribuloside (12) and sulfonoquinovosyldiacylglyceride (13). Among these, six compounds (8–13) are reported for the first time from this plant. Cytotoxicity evaluation of the compounds against five cancer cell lines (CHO, HepG2, HeLa, A-431 and MCF-7) shows promising IC₅₀ values for compounds 4, 6 and 12.     

Two new quercetin glycoside derivatives from the fruits of Gardenia jasminoides var. radicans

Two new quercetin glycoside derivatives named quercetin-3-O-[2-O-trans-caffeoyl-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside] (1) and quercetin-3-O-[2-O-trans-caffeoyl-β-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside] (2) along with three known flavonoids, 5-hydroxy-6,7,3′,4′,5′-pentamethoxyflavone (3), 5,7-dihydroxy-8-methoxyflavone (4) and kaempferol 3-O-β-d-glucopyranoside (5), were isolated from the fruits of Gardenia jasminoides var. radicans. The structures of the new compounds were determined by means of extensive spectroscopic analysis (1D, 2D NMR and HR-ESI-MS), glycoside hydrolysis and sugar HPLC analysis after derivatisation. This is the first report on the isolation of a pair of compounds with α or β-l-rhamnopyranosyl configuration from plant and the first detail assignment of their NMR data.     

A new sesquiterpene from Kalimeris integrifolia

A new sesquiterpene kalinturoside A (1), and 17 known compounds friedelan-3-ol (2), 24-ethyl-5a-cholesta-7, 22(E)-dien-3-one (3), friedelin (4), syringaresinol (5), α-spinasterol (6), ciwujiatone (7), syringic acid (8), scopoletin (9), apocynin (10), 1-(3-hydroxy-4, 5-dimethoxyphenyl)ethan-1-one (11), apigenin (12), 5-hydroxymethylfurfural (13), stigmasterol-3-O-β-d-glucopy-ranoside (14), bidenoside C (15), citrusin (16), irioresinol A (17) and syringaresinol-4-O-β-d-glucopyranoside (18) were isolated from the herbs of Kalimeris integrifolia. The structures of these compounds were elucidated using spectroscopic techniques such as NMR and MS. All of the compounds were isolated from this genus for the first time.     

Chemical constituents of Silene montbretiana

A new steroidal glycoside, 3-O-β-d-glucopyranosyl-3β,25-dihydroxy-5β-cholest-7-en-6-one 25-O-β-d-glucopyranoside (1), together with six known steroidal derivatives (2-7), one cerebroside (8) and one flavonoid (9) were isolated from Silene montbretiana Boiss (Caryophyllaceae), a perennial herb growing mainly in the Middle and East Anatolia, Azerbaijan, Iran, and Turkey. Their structures were established by the extensive use of 1D and 2D NMR experiments along with ESI-MS analyses. The cytotoxicity against the cancer A549 (human alveolar basal carcinoma) and Hela (human epitheloid cervix carcinoma) cell lines has been evaluated. None of the tested compounds, in a range of concentrations between 12.5 and 100 μM, caused a significant reduction of the cell number.     

A new myrsinol-type diterpene polyester from Euphorbia dracunculoides Lam

A new myrsinol-type diterpene polyester, 14-deoxo-3β-O-propinoyl-2α,5α,7β,15β-tetra-O-acetyl-14α-O-benzoyl-myrsinol (1), and its known analogue, 14-deoxo-3β-O-prorionyl-5α,15β-di-O-acetyl-7β-O-nicotinoyl-myrsinol-14β-acetate (2), together with a monoterpenoid, pubinernoid A (3), two indole alkaloids, neoechinulin A (4) and dihydroxyisoechinulin A (5), two benzene derivatives, siringin (6) and (3-methoxyphenyl) acetic acid (7), were isolated from the 70% acetone extract of the aerial parts of Euphorbia dracunculoides Lam. Their structures were elucidated on the basis of spectroscopic evidence and comparison with literature reports. The absolute configuration of 1 was deduced by comparing experimental and calculated ECD spectra. Among them, compounds 4 and 5 were first obtained from the plant source. In addition, the ¹³C NMR data of compound 2 was reported for the first time.     

New coumarin from the roots of Prangos pabularia

The new coumarin 1, yuganin A (7-methoxy-8-((1S,2S)-1,2,3-trihydroxy-3-methylbutyl)-2H-chromen-2-one) along with nine known coumarins, heraclenol 3′-O-β-D-glucopyranoside (2), oxypeucedanin hydrate 3′-O-β-D-glucopyranoside (3), heraclenol (4), oxypeucedanin hydrate (5), osthole (6), oxypeucedanin (7), heraclenin (8), isoimperatorin (9), imperatorin (10) and the disaccharide sucrose (11), have been isolated from the roots of Prangos pabularia, and the structures of these isolated compounds were elucidated by spectroscopic means, especially, UV, HR-ESIMS, and 1D and 2D NMR spectroscopy. Furthermore, the anti-melanogenic effect of yuganin A and its inhibitory effect on B16 cells were evaluated. Yuganin A may be useful in the treatment of hyperpigmentation and as a skin-whitening agent in the cosmetics industry.     

Three new acyltyramines from Anisodus luridus Link et Otto (Solanaceae)

Three new acyltyramines, N-[2-(4-hydroxyphenyl)ethyl]hentriacontanamide (1), N-[2-(4-hydroxyphenyl)ethyl]nonacosanamide (2) and N-[2-(4-hydroxyphenyl)ethyl]heneicosanamide (3) have been isolated from n-hexane extract of leaves of Anisodus luridus (Solanaceae). Successive extraction of defatted leaves of A. luridus with methanol afforded a residue on removal of solvent under reduced pressure. Residue was partitioned by means of chloroform and n-butanol. Chromatographic resolution of n-BuOH extract afforded six known compounds, apigenin (4), luteolin (5), quercetin (6), quercetin 3-O-α-l-rhamnoside (7), kaempferol 3-O-α-rhamnoside (8) and quercetin 3-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (9). The structures of the isolated compounds were assigned with the help of spectroscopic techniques. This is the first report of isolation of these compounds from this plant.     

A new triterpenoid saponin from Clinopodium chinense (Benth.) O. Kuntze

A new triterpene saponin, 3β,16β,23α,28β,30β-pentahydroxyl-olean-11,13(18)-dien-3β-yl-[β-d-glucopyranosyl-(1→2)]-[β-d-glucopyranosyl-(1→3)]-β-d-fucopyranoside, was named Clinoposaponin D (1), together with six known triterpene saponins, buddlejasaponin IVb (2), buddlejasaponin IVa (3), buddlejasaponin IV (4), clinopodisides D (5), 11α,16β,23,28-Tetrahydroxyolean-12-en-3β-yl-[β-d-glucopyranosyl-(1→2)]-[β-d-glucopyranosyl-(1→3)]-β-d-fucopyranoside (6) and prosaikogenin A (7), and two known triterpenes, saikogenin A (8) and saikogenin F (9) were isolated from Clinopodium chinense (Benth.) O. Kuntze. Their structures were elucidated on the basis of 1D, 2D NMR and MS analysis. Meanwhile, the effects of all compounds on rabbit platelet aggregation and thrombin time (TT) were investigated in vitro. Compounds 4 and 7 had significant promoting effects on platelet aggregation with EC₅₀ value at 53.4 and 12.2 μM, respectively. In addition, the highest concentration (200 μM) of compounds 2 and 9 shortened TT by 20.6 and 25.1%, respectively.     

L-鼠李糖基(氨基)硫脲类化合物的合成

以L-鼠李糖为起始原料, 制备1-溴-2,3,4-三-O-乙酰基-β-L-吡喃型鼠李糖, 然后在甲苯中与Pb(SCN)₂作用, 得到中间体2,3,4-三-O-乙酰基-α-L-吡喃型鼠李糖基异硫氰酸酯(1). 利用2,3,4-三-O-乙酰基-α-L-吡喃型鼠李糖基异硫氰酸酯易发生亲核加成的性质, 在不同溶剂中, 与取代的苯并噻唑胺(2a～2f)、取代的苯并噻唑肼(2g～2l)、氧化和非氧化的哒嗪酮甲酰肼(2m, 2n)以及取代的嘧啶胺(2o, 2p)反应, 合成了16种新的(氨基)硫脲类化合物3a～3p. 所有化合物的结构均经IR, ¹H NMR, LC-MS和元素分析确证, 并对它们的生物活性做了初步测试.     

Glycosides of ursane-type triterpenoid,benzophenone, and iridoid from Vangueria agrestis (Fadogia agrestis) and their anti-infective activities

Abstract

Four ursane-type triterpenoid glycosides (1-4), two benzophenone glycosides (5 and 6), and one iridoid glucoside (7) were isolated and characterized from the dried roots of Vangueria agrestis. Compounds 1 (3-O-[α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl]pomolic acid 28-O-β-D-glucopyranosyl ester) and 5 (2-O-[β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyl]-6,4′-dihydroxy-4-methoxy benzophenone) were found to be new metabolites. The identity of all compounds has been accomplished, primarily, based on 1 D and 2 D NMR and HRESMS analysis. Compounds 6 and 2, showed inhibitory effect against Trypanosoma brucei with IC₅₀ 22.3 µM for 6 and IC₅₀ 11.1 µM, IC₉₀ 12.3 µM for 2.