A new chromone from Ficus lyrata

A new chromone, named 5,6-dihydroxy-2-methylchromone (FL-2), along with seven known flavonoids, 5-hydroxy-7,3,3',4'-tetramethoxyflavone (FL-3), 5,4'-dihydroxy-6,7,8-trimethoxyflavone (FL-4), 5,4'-dihydroxy-7,8-dimethoxyflavone (FL-5), 4-methoxychalcone (FL-6), 7,4'-dimethoxyapigenin (FL-7), 5,7,4'-trihydroxy-2',3',6'-trimethoxyisoflavone (FL-8 a rare flavonoid), acacetin-7-O-glucoside (FL-9) and acacetin-7-O-neohesperidoside (FL-10), and beta-sitosterol-D-glucoside (FL-1) have been isolated from the leaves of Ficus lyrata. Their structures have been established on the basis of chemical and spectral evidence (IR, UV, 1H NMR, 13C NMR and mass spectra).     

Flavonoids from the leaves of Pleioblastus argenteastriatus

A new flavonoid, 5,7,3′-trihydroxy-6-C-β-d-digitoxopyranosyl-4′-O-β-d-glucopyranosyl flavonoside (1), along with four known flavonoids 5,7,4′-trihydroxy-3′,5′-dimethoxy flavone (2), 5,3′,4′-trihydroxy-7-O-β-d-glucopyranosyl flavonoside (3), 5,4′-dihydroxy-3′,5′-dimethoxy-7-O-β-d-glucopyranosyl flavonoside (4), 5,3′,4′-trihydroxy-6-C-[β-d-glucopyranosyl-(1 → 6)]-β-d-glucopyranosyl flavonoside (5) were isolated from 95% EtOH extract of the leaves of Pleioblastus argenteastriatus. Their structures were determined on the basis of spectroscopic techniques and chemical methods.     

A Novel 4′-O-Diglycoside of Decarboxyrosmarinic Acid from Blepharis ciliaris

Abstract

A novel natural phenolic 1 was isolated from the hydroalcoholic extract of the aerial parts of Blepharis ciliaris (L.) B.L. Burtt (Acanthaceae), in addition to apigenin 7-O-glucoside 2 and apigenin-7-O-(3″-acetyl-6″-E-p-coumaroyl glucoside) 3. The structure of 1 was established as 3′,4′-dihydroxy-β-phenyl ethyl caffeate-4′-β-O-D-galactopyranosyl-(1′″→4″)-α-O-L-rhamnopyranoside [= 9′-decarboxy rosmarinic acid-4′-O-(1→4)-galactosyl rhanmoside]. Structures were determined by conventional methods of analysis, as well as by different MS and NMR techniques.     

Two new flavonoid glycosides from Artemisia frigida Willd.

An investigation of the n-BuOH-soluble fraction from the aerial parts of Artemisia frigida has led to the isolation of two new flavonoid glycosides, named friginoside A and friginoside B. Their structures were characterized as 5,7-dihydroxy-3′,4′,5′-trimethoxy flavone 7-O-β-d-glucuronide (1) and 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone 7-O-β-d-glucuronyl-(1 → 2)O-β-d-glucuronide (2) on the basis of 1D and 2D NMR spectral analysis.     

Two new chalcones from Clerodendrum phlomidis

Two new chalcones, 3,2′,3′-trihydroxy-4′-methoxychalcone (1) and 3,2′-dihydroxy-4′,6′-dimethoxychalcone (2), were isolated from the seeds of Clerodendrum phlomidis together with three known flavonoids, 5-hydroxy-7-methoxyflavanone (3), 5-hydroxy-7-methoxyflavone (4), and kaempferol-3-O-α-l-rhamnopyranoside (5). The structures of the new compounds 1 and 2 have been established mainly on the basis of 1D and 2D NMR studies.     

Further flavonol and iridoid glycosides from Ajuga remota aerial parts

Five new iridoid glycosides characterised as 6-keto-8-acetylharpagide (1), 6,7-dehydro-8-acetylharpagide (2), 7,8-dehydroharpagide (3), 8-acetylharpagide-6-O-β-glucoside (4), harpagide-6-O-β-glucoside (5) together with three flavonol glycosides, myricetin 3-O-rutinoside-4′-O-rutinoside (6), myricetin 3-O-rutinoside-3′-O-rutinoside (7) and isorhamnetin 3-O-rutinoside-7-O-rutinoside-4′-O-β-glucoside (8) have been isolated from the aerial parts of Ajuga remota. Also isolated were two known compounds ajugarin IV and ajugarin V. Their structures were established using spectroscopic methods including UV, IR, FAB-MS, HR-MS, 1D and 2D NMR techniques.     

Two antigenotoxic chalcone glycosides from Mentha longifolia subsp. longifolia

Abstract

Context: Mentha L. (Labiatae) species (mint) with their flavoring properties have been used in food industries for centuries. Besides they have a great importance in drug development and medicinal applications due to various bioactive compounds of several members of the genus.

Objective: The aim of this study was to isolate bioactive compounds with antimutagenic potential by bio-guided fractionation and determine their structures by spectroscopic methods.

Materials and methods: The structural elucidation of the isolated compounds was done based on spectroscopic methods, including MALDI-MS, UV, IR, and 2D NMR experiments, and the bio-guided fractionation process was done by using the Ames/Salmonella test system. Henceforth, solely genotoxic and antigenotoxic potential of the new compounds were also confirmed up to 2?µM/plate by using the same test system.

Results: Two new chalcone glycosides: (βR)-β,3,2′,6′-tetrahydroxy-4-methoxy-4′-O-rutinosyldihydrochalcone and (βR)-β,4,2′,6′-tetrahydroxy-4′-O-rutinosyldihydrochalcone, were isolated from Mentha longifolia (L.) Hudson subsp. longifolia, together with known six flavonoid glycosides and one phenolic acid: apigenin-7-O-glucoside, luteolin-7-O-glucoside, apigenin-7-O-rutinoside, luteolin-7-O-rutinoside, apigenin-7-O-glucuronide, luteolin-7-O-glucuronide, rosmarinic acid. According to the antimutagenicity results, both new test compounds significantly inhibited the mutagenic activity of 9-aminoacridine in a dose-dependent manner at the tested concentrations from 0.8 to 2?µM/plate. (βR)-β,4,2′,6′-Tetrahydroxy-4′-O-rutinosyldihydrochalcone showed the maximum inhibition rate as 75.94% at 2?µM/plate concentration.

Conclusions: This is the first report that two new chalcone glycosides were isolated from Mentha longifolia subsp. longifolia and their antimutagenic potentials by using mutant bacterial tester strains. In conclusion, the two new chalcone glycosides showed a significant antigenotoxic effect on 9-aminoacridine-induced mutagenesis at tested concentrations.     

Two new compounds from the dry leaves of Pleioblastus amarus (Keng) keng f.

Two new compounds, xylitol 1-O-(6′-O-p-hydroxylbenzoyl)-glucopyranoside (1) and bambulignan B (2), together with three known ones gastrodin (3), glucovanillin (4), and rel-(7S,7′R,8R,8′S)-4,4′-dihydroxy-3,3′,5,5′-tetramethoxy-7,7′-epoxyligna-9,9′-diol-9(or)9′-O-β-glucopyranoside (5), were isolated from the 95% EtOH extract of the dry leaves of Pleioblastus amarus (Keng) keng f. Their structures were determined by UV, IR, HR-ESI-MS, CD, and 1D and 2D NMR data analyses as well as GC experiments.     

Microbial transformation of naringenin derivatives

Microbial transformations of (±)-7-O-prenylnaringenin (7-PN, 1) and (±)-7-O-allylnaringenin (7-AN, 2) have isolated four metabolites (3–6). Structures of these novel compounds were identified as 5,4′-dihydroxy-7-O-[(2E)-4-hydroxy-3-methyl-2-buten-1-yl]flavanone (3), 5,4′-dihydroxy-7-O-(2,3-dihdroxy-3-methylbutyl)flavanone (4), 5,4′-dihydroxy-7-O-(2,3-dihdroxypropyl)flavanone (5), and 5-O-β-D-glucopyranosyl-7-O-allyl-4′-hydroxyflavanone (6) based on spectroscopy. Compounds 1–6 were evaluated for their radical scavenging capacity using DPPH (2,2-diphenyl-1-picrylhydrazyl). The derivatives 3–6 exhibited more potent antioxidant activity than their corresponding substrates 1 and 2.     

密蒙花黄酮类化合物的分离和鉴定

从密蒙花(Buddleia officinalis Maxim)的花蕾中分离得到8个黄酮类化合物,其小3个甙元:刺槐素(acacetin,1),芹菜素(apigenin,2),木犀草素(luteolin,3);5个甙:密蒙花新甙(neobudofficide,4),蒙花甙(linarin=acaciin,5),木犀草素7-O-芸香糖甙(6),木犀草素-7-O-葡萄糖甙(7),秋英甙(cosmosiin,8)。化合物4为新化合物,用化学和波谱法确定其结构为5.7-二羟基-4'-甲氧基黄酮-7-O-α-L-吡喃鼠李糖基-(1→2)-[α-L-吡喃鼠李糖基-(1→6)]-β-D-吡喃葡萄糖甙,除化合物1和5以外,其它化合物均为首次从密蒙花中得到。     

Two new neolignan glucosides from Arctii Fructus

Two new neolignan glucosides named (7S, 8R)-4,7,9,9′-tetrahydroxy-3,3′-dimethoxyl-7′-oxo-8-4′-oxyneolignan-4-O-β-d-glucopyranoside (1) and (7′S, 8′R, 8S)-4,4′,9′-trihydroxy-3,3′-dimethoxy-7′,9-epoxylignan-7-oxo-4-O-β-d-glucopyranosyl-4′-O-β-d-glucopyranoside (2), together with two small molecular peptides named 3-benzyl-6-(1-hydroxyethyl)-2,5-piperazinedione (3) and 3-benzyl-2,5-piperazinedione (4), were isolated from the extract of Arctii Fructus. Their structures and absolute configurations were elucidated by various spectroscopic methods (IR, HR-ESI-MS, 1D and 2D NMR, and CD).     

Two new compounds from the leaves of Indocalamus latifolius

Two new compounds, erythro-syringylglycerol-9-O-trans-4-hydroxycinnamate 7-O-β-d-glucopyranoside (1) and indocalatin A (2), together with three known ones, 5,7,3′-trihydroxy-6-C-β-d-digitoxopyranosyl-4′-O-β-d-glucopyranosyl flavonoid (3), 5,4′-dihydroxy-3′,5′-dimethoxy-7-O-[β-d-apiose-(1→2)]-β-d-glucopyranosyl flavonoid (4), and tricin-6-C-β-boivinopyranosyl-8-C-β-glucopyranoside (5), were isolated from the 95% EtOH extract of Indocalamus latifolius leaves. Their molecular structures were determined by UV, IR, HRESIMS, CD, and 1D and 2D NMR data analyses.     

月腺大戟根中的乙酰间苯三酚类衍生物

目的:研究月腺大戟根中的乙酰间苯三酚类衍生物。方法:利用硅胶柱色谱分离、纯化乙酰间苯三酚类化合物;经化学反应、理化常数测定和波谱分析等鉴定结构。结果:分离得到5个乙酰间苯三酚类化合物:2,4-二羟基-6-甲氧基-3-甲基苯乙酮(I),3,3′-二乙酰基-4,4′-二甲氧基-2,2′,6,6′-四羟基二苯甲烷(I),3,3′-二乙酰基-4,4′-二甲氧基-2,2′,6,6′-四羟基二苯甲烷-6′-O-β-D-葡糖苷(II),2,4-二羟基-6-甲氧基-3-甲基苯乙酮-4-O-β-D-葡糖苷(IV),2,4-二羟基-6-甲氧基-3-甲基苯乙酮-4-O-β-D-木糖基(1→6)-O-β-D-葡糖苷(V)。结论:(II)和(V)为新化合物,分别命名为月腺大戟苷B和月腺大戟苷C。     

A new meta-homoisoflavane from the fresh stems of dracaena cochinchinensis

A new meta-homoisoflavane, 10,11-dihydroxydracaenone C (1), together with 7,4′-dihydroxyflavone (2), 7,4′-dihydroxyflavane (3), 4,4′-dihydroxy-2-methoxychalcone (4), 4,4′-dihydroxy-2-methoxydihydrochalcone (5), 7,4′-dihydrohomoisoflavanone (6), 7,4′-homoisoflavane (7), lophenol (8), β-sitosterol (9), stigma-5, 22-diene-3-ol (10), 1-(4′-O-β-d-glucopyranosyl)benzyl-ethan-2-ol (11), 3,4-dihydoxy-1-allylbenezene-4-O-α-l-rhamnopyranosyl-(1 → 6)-O-β-d-glucopyranoside (12), 1-hydroxy-3,4,5-trimethoxybenzene-1-O-α-l-apiopyranosyl-(1 → 6)-O-β-d-glucopyranoside (13), and tachioside (14) have been isolated from the fresh stems of Dracaena cochinchinensis. Their structures have been established by spectroscopic analysis, especially by 2D NMR. This is the first time compounds 11, 13, 14 have been isolated from Dracaena.     

Three new C-flavonoids from Corallodiscus flabellata

Three new C-glycosylflavones, named 5,7,4′-trihydroxy-6-methoxy-8-C-[β-d-xylopyranosyl- (1 → 2)]-β-d-glucopyranosyl flavonoside (1), 5,7,4′-trihydroxy-8-methoxy-6-C-[β-d-xylopyranosyl-(1 → 2)]-β-d-glucopyranosyl flavonoside (2), and 5,3′,4′-trihydroxy-7,8-dimethoxy-6-C-[β-d-xylopyranosyl-(1 → 2)]-β-d-glucopyranosyl flavonoside (3), along with two known compounds 5,4′-dihydroxy-7-methoxy-6-C-glucopyranosyl-flavonoside (4), 3-methoxy-4-hydroxymethyl benzoate (5) were isolated from 70% acetone extract of Corallodiscus flabellata. Their structures were identified on the basis of spectroscopic techniques and chemical methods.     

东风桔化学成分研究

东风桔是芸香科酒饼簕属植物,学名为Atalantia buxifolia (Poir)Oliv,民间用于去瘀去痛,顺气化痰,治跌打肿痛,风湿痛,疟疾。药理试验证明,东风桔叶有明显的抗疟作用。有效成分不明。东风桔化学成分前人有过报道,但国内对东风桔叶化学成分尚末进行过研究。为阐明其有效成分,我们对其化学成分进行了研究,从叶子的石油醚提取部位     

Two new acetylated flavan glycosides from rhizomes of the fern Abacopteris penangiana

Two new acetylated flavan glycosides (2S,4R)-4,5,7-trihydroxy-4′-methoxy-6,8-dimethylflavan-5-O-β-D-6-acetylglucopyranoside-7-O-β-D-glucopyranoside (1) and (2S,4R)-5,7-dihydroxy-4,4′-dimethoxy-6,8-dimethylflavan-5-O-β-D-6-acetylglucopyranoside-7-O-β-D-glucopyranoside (2) were isolated from the rhizomes of Abacopteris penangiana. Their structures were elucidated on the basis of spectroscopic methods including IR, HR-ESI-MS, 1D and 2D NMR, and chemical evidences.     

Cytotoxic C-Methylated Chalcones from Syzygium samarangense.

Abstract

The flavonoids 2′-hydroxy-4′,6′-dimethoxy-3′-methylchalcone (1), 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (2), 2′,4′-dihydroxy-6′-methoxy-3′-methylchalcone (3), 2′,4′-dihydroxy-6′-methoxy-3′-methyldihydrochalcone (4) and 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethyldihydrochalcone (5), isolated from Syzygium samarangense. (Blume) Merr. & L.M. Perry (Myrtaceae), were subjected to cytotoxicity testing using the dimethylthiazoldiphenyl tetrazolium (MTT) assay. The cell lines used were the Chinese hamster ovarian (CHO-AA8) and the human mammary adenocarcinoma, (MCF-7 and SKBR-3). Among the test compounds, 2 exhibited significant differential cytotoxicity against the MCF-7 cell line with an IC₅₀ of 0.0015 ± 0.0001 nM. It was also cytotoxic against the SKBR-3 cell line with an IC₅₀ of 0.0128 ± 0.0006 nM. Doxorubicin, the positive control, had an IC₅₀ of 2.60 ± 0.28 × 10^?4 nM against the MCF-7 cell line and an IC₅₀ of 2.76 ± 0.52 × 10^?5 nM against the SKBR-3 cell line. When tested in a mechanism-based yeast bioassay for detecting DNA-damaging agents using genetically engineered Saccharomyces cerevisiae. RS322Y (RAD52) mutant strain and (LF15/11) (RAD+) wild-type strain, 2 showed significant selective cytotoxicity against the RAD52 yeast mutant strain. It had an IC₁₂ of 0.1482 nM, as compared with the positive control, streptonigrin, which had an IC₁₂ of 0.0134 nM. Hence, 2 is a cytotoxic natural product with potential anticancer application.     

Development and Validation of Liquid Chromatography Method for Quantification of the Active Markers of Hintonia standleyana. and Hintonia latiflora. Crude Drugs

Abstract

The infusions prepared from the stem-bark of Hintonia latiflora. (Sesse et Mociño ex DC) Bullock or Hintonia standleyana. Bullock (Rubiaceae) are indistinctly used in Mexican traditional medicine for the treatment of non–insulin-dependent diabetes mellitus and malaria fevers. Suitable high-performance liquid chromatography (HPLC)-UV methods for quantitative determination of 5-O.-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-7-methoxy-3′,4′-dihydroxy-4-phenylcoumarin (1) and 5-O.-[β-d-xylopyranosyl-(1 → 6)-β-d-glucopyranosyl]-7-methoxy-3′,4′-dihydroxy-4-phenylcoumarin (2) in the infusions of H. standleyana. and H.. latiflora., respectively, were established. Coumarins 1 and 2 are the major antihyperglycemic compounds found in the infusions prepared from stem-bark of H. standleyana. and H.. latiflora., respectively, and are proposed as the active markers. The methods were found to be reliable, reproducible, and accurate.