Two new isoflavonoids from the roots of Dalbergia congesta (Grah)

A systematic examination of the roots of Dalbergia congesta, yielded a new oligomeric isoflavonoid (1), a new tetramethoxy isoflavone (2) along with two known compounds, an isoflavone dalspinin (3) and a benzophenone, cearoin (4). On the basis of chemical and spectral evidences, compounds 1 and 2 were determined to be 5,7-dihydroxy-6,4'-dimethoxy-6'[2'-hydroxy-2'(2',5'-dimethoxy neoflavonyl) ethenyl] isoflavone (dalcongestin) and 5,7-dihydroxy-2',3',5',6'-tetramethoxy isoflavone, respectively.     

黄甘草异黄酮成分的研究

从黄甘草(Glycyrrhiza eurycarpa P.C.Li)根及根茎中分得五个异黄酮化合物,根据理化性质及光谱(UV,MS,¹HNMR,¹³CNMR,NOE,HMBC)数据分析,化合物I的结构推定为7,2′,4′-三羟基-3′-异戊烯基异黄酮,为一新化合物,命名为黄甘草异黄酮A(eurycarpinA)。化合物I的结构推定为7,2′-二羟基-(2″,3″∶4′,3′)-6″,6″-二甲基吡喃异黄酮,为一新的天然产物,命名为黄甘草异黄酮B(eurycarpinB)。其余化合物分别鉴定为 licoisoflavone A(III),毛蕊异黄酮(calycosin,IV)和芒柄花素(formononetin,V)。化合物II～V均为首次从本植物中得到。     

Method development and validation for isoflavones in soy germ pharmaceutical capsules using micellar electrokinetic chromatography

The separation of six soy isoflavones (Glycitein, Daidzein, Genistein, Daidzin, Glycitin and Genistin) was approached by a 3² factorial design studying MEKC electrolyte components at the following levels: methanol (MeOH; 0–10%) and sodium dodecylsulfate (SDS; 20–70 mmol L⁻¹); sodium tetraborate buffer (STB) concentration was kept constant at 10 mmol L⁻¹. Nine experiments were performed and the apparent mobility of each isoflavone was computed as a function of the electrolyte composition. A novel response function (RF) was formulated based on the productory of the mobility differences, mobility of the first and last eluting peaks and the electrolyte conductance. The inspection of the response surface indicated an optimum electrolyte composition as 10 mmol L⁻¹ STB (pH 9.3) containing 40 mmol L⁻¹ SDS and 1% MeOH promoting baseline separation of all isoflavones in less than 7.5 min.

The proposed method was applied to the determination of total isoflavones in soy germ capsules from four different pharmaceutical laboratories. A 2 h extraction procedure with 80% (v/v) MeOH under vortexing at room temperature was employed. Peak assignment of unknown isoflavones in certain samples was assisted by hydrolysis procedures, migration behavior and UV spectra comparison. Three malonyl isoflavone derivatives were tentatively assigned. A few figures of merit for the proposed method include: repeatability (n = 6) better than 0.30% CV (migration time) and 1.7% CV (peak area); intermediate precision (n = 18) better than 6.2% CV (concentration); recoveries at two concentration levels, 20 and 50 μg mL⁻¹, varied from 99.1 to 103.6%. Furthermore, the proposed method exhibited linearity in the concentration range of 1.6–50 μg mL⁻¹ (r² > 0.9999) with LOQ varying from 0.67 to 1.2 μg mL⁻¹. The capsules purity varied from 93.3 to 97.6%.     

Two new isoflavonoids from the roots of Dalbergia congesta (Grah)

A systematic examination of the roots of Dalbergia congesta, yielded a new oligomeric isoflavonoid (1), a new tetramethoxy isoflavone (2) along with two known compounds, an isoflavone dalspinin (3) and a benzophenone, cearoin (4). On the basis of chemical and spectral evidences, compounds 1 and 2 were determined to be 5,7-dihydroxy-6,4′-dimethoxy-6′[2″-hydroxy-2″(2?,5?-dimethoxy neoflavonyl) ethenyl] isoflavone (dalcongestin) and 5,7-dihydroxy-2′,3′,5′,6′-tetramethoxy isoflavone, respectively.     

红花岩黄芪黄酮类成分研究

目的对红花岩黄芪化学成分进行研究。方法用溶剂法、色谱法提取分离化学成分,用波谱法鉴定其结构。结果从红花岩黄芪中分离得到6个化合物：β-谷甾醇(1),芒柄花素(7羟基-4′-甲氧基异黄酮)(2),白桦脂酸(3),1,7-二羟基-3,9-二甲氧基紫檀烯(4),5,7-二羟基-4′-甲氧基-8-异戊烯基异黄酮(5)和金雀花异黄素(5,7-二羟基-4′-甲氧基异黄酮)(6)。结论化合物4为新化合物,其他均为首次从该植物中获得。     

New 6-O-acyl isoflavone glycosides from soybeans fermented with Bacillus subtilis (natto). I. 6-O-succinylated isoflavone glycosides and their preventive effects on bone loss in ovariectomized rats fed a calcium-deficient diet

Three new 6-O-acylated isoflavone glycosides were isolated from soybeans fermented with Bacillus subtilis (natto) and identified as daidzein 7-O-beta-(6'-O-succinyl)-D-glucoside (1), genistein 7-O-beta-(6'-O-succinyl)-D-glucoside (2), and glycitein 7-O-beta-(6'-O-succinyl)-D-glucoside (3) on the basis of spectral data and chemical transformations. During fermentation, the content of the isoflavone glycosides first decreased and then increased, whereas the corresponding 6'-O-succinyl derivatives first accumulated and then decreased, in either soybeans or soybean cooking solution. These changes suggest that enzymatic interconversion of isoflavone glycosides and the corresponding 6'-O-succinylated derivatives occurs in these media during fermentation. The 6-O-succinylated isoflavone glycosides 1, 2 and 3 accounted for 4.8, 7.2 and 0.6%, respectively, of the total isoflavones in commercial fermented soybeans (Japanese natto). Oral administration of 1 or 2 alone for 4 weeks at a dose of 50 mg/kg/d prevented bone loss in ovariectomized (ovx) rats fed a calcium-deficient diet, being as effective as the positive controls, daidzin and genistin, respectively. Compound 1 seems to be proestrogenic, like daidzin, which suppresses bone resorption to prevent bone loss after ovariectomy by directly acting on bone sites, while 2 appears to have a different mechanism of action, like that of genistin.     

A New Isoflavone Glucoside from Pterocarpus santalinus

Abstract

A new isoflavone glucoside (1) together with the known santal has been isolated from the heartwood of Pterocarpus santalinus. Based on spectral methods, the structure of the new compound was elucidated as 4′,5-dihydroxy 7-O-methyl isoflavone 3′-O-β-D-glucoside.     

土茯苓化学成分研究(IV)

Smilax glabra is a wellknown traditional Chinese medicine which has been used clinically to prevent leptospirosis, to treat syphilis, and acute bacterial dysentery, etc. Its extracts showed antitumor and antiatherosclerosis activiy. A new isoflavone, 7,6′-dihydroxy 3′-methoxy isoflavone (1), along with two known compounds taxifolin (2) and astilbin (3), have been isolated from the roots of Smilax glabra. The structures were elucidated by spectroscopic methods including 2DNMR techniques.     

A patent review of the therapeutic potential of isoflavones (2012-2016)

Introduction: Isoflavones are well-studied natural products isolated from natural sources with interesting chemodiversity and possess a wide variety of biological effects. Moreover, chemical modifications based on the isoflavone scaffold, has generated synthetic chemodiversity to enhance the bioactivities of isoflavones.

Areas covered: The current review summarizes the discovery of new chemotherapeutic agents possessing the isoflavone skeleton. This review incorporates patents filed between 2012 and 2016 mostly related to anticancer, antidiabetic, antimicrobial, anti-HIV, anti-gastric ulcer, anti-gastritis, antiparasitic and some other biological effects demonstrated by isoflavone analogs.

Expert opinion: The number of interesting patents published during the five year period (2012–2016) on the therapeutic potential of isoflavones indicated the importance of this molecule. Natural isoflavones possess potent anticancer, anti-HIV and antidiabetic activities and chemical analogs of natural isoflavones increase the abovementioned biological effects. Additionally isoflavones have only been tested for a limited number of biological activities and thus future research should focus on additional biological activities viz., anti-inflammatory, antimalarial, and anti-leishmanial effects. However, the absence of SAR studies and in vivo data restricted the rational design of more potent isoflavone analogs and we believe that in order to get lead compounds, there needs to be a greater focus on SAR and in vivo studies.     

Studies on the chemical constituents of Psoralea corylifolia L

A new isoflavone, corylinin (1), along with six known compounds, isopsoralen (2), psoralen (3), sophoracoumestan A (4), neobavaisoflavone (5), daidzin (6) and uracil (7), have been isolated from the dried fruits of Psoralea corylifolia L. The structure of 1 was established as 7,4'-dihydroxy-3'-[(E)-3,7-dimethyl-2,6-octadienyl]isoflavone on the basis of the spectroscopic methods. Structures of the known compounds were identified by comparison of the literature.     

Chemical constituents from Belamcanda chinensis

One new flavone and one new isoflavone glycoside were isolated along with 15 known compounds from the rhizome of Belamcanda chinensis (Iridaceae), and their structures were characterised as 5,4'-dihydroxy-6,7-methylenedioxy-3'-methoxyflavone (1) and 3',5'-dimethoxy irisolone-4'-O-beta-D-glucoside (2) on the basis of spectroscopic methods.     

In vitro BACE-1 inhibitory phenolic components from the seeds of Psoralea corylifolia

A new isoflavone, neocorylin ( 1) was isolated from the seeds extract of Psoralea corylifolia L. (Fabaceae), together with eight known constituents ( 2 - 9), i. e., bakuchiol ( 2), psoralen ( 3), bavachromene ( 4), isobavachromene ( 5), bavachalcone ( 6), isobavachalcone ( 7), 7,8-dihydro-8-(4-hydrophenyl)-2,2-dimethyl-2 H,6 H-[1,2- B:5,4- B']dipyran-6-one ( 8), and bavachinin ( 9). The structure of the new isoflavone 1 was elucidated as 7-hydroxy-3-[2-methyl-2-(4-methylpenten-3-yl)-2 H-chromen-6-yl]-4 H-chromen-4-one by spectroscopic analyses. Neocorylin ( 1) as well as related compounds 2, 4 - 6, 8 and 9 exhibited a significant inhibitory effect on baculovirus-expressed BACE-1 in vitro.     

金雀异黄素4′-二氟甲醚化衍生物的合成

目的 合成金雀异黄素4′-二氟甲醚化衍生物。方法 金雀异黄素与HCF2Cl、NaOH在水和二氧六环的混合液中发生二氟甲醚化反应，生成7，4′-二-二氟甲氧基-5-羟基异黄酮（2）、7-二氟甲氧基-5，4′_二羟基异黄酮（3）和4′-二氟甲氧基-5，7-二羟基异黄酮（4），再经甲醚化反应得到7-二氟甲氧基-5，4′-二甲氧基异黄酮（5）和4′-二氟甲氧基-5，7-二甲氧基异黄酮（6）。结果 化合物的结构经MS、^1H-NMR、^13C-NMR、^19F-NMR等进行了确证，化合物（4）和（6）为首次合成的新化舍物。结论 为金雀异黄素4′-二氟甲醚化衍生物的合成提供了实验基础。     

黄芪中主要异黄酮苷及其苷元的含量分析

采用高效液相色谱-二极管阵列检测器（HPLC/DAD）方法测定黄芪药材和饮片中主要异黄酮苷及其苷元的含量,并采用高效液相质谱联用技术（LC/MS^n）鉴定主要未知色谱峰的结构。测定了黄芪药材及饮片中2个主要异黄酮苷：毛蕊异黄酮苷（1）,芒柄花苷（2）及其相应苷元毛蕊异黄酮（3）,芒柄花素（4）的含量,并鉴定了两个主要未知色谱峰的结构分别为毛蕊异黄酮苷6′″-O-丙二酸酯（U1）和芒柄花苷6′″-O-丙二酸酯（U2）。结果表明黄芪药材中异黄酮苷类成分的含量高于饮片,而苷元含量则低于饮片。另外,将黄芪药材粉末用水润湿后在35℃放置24小时,其中的异黄酮苷及其丙二酸酯类成分几乎全部转变成了苷元。黄芪中异黄酮苷类成分在一定条件下可转化为苷元,异黄酮苷和苷元在黄芪药材与饮片中含量的不同可能与饮片制备过程中苷类成分的酶解有关。     

Caragin, a new isoflavone from Caragana conferta

Caragin (1), a new isoflavone, has been isolated from the hexane soluble fraction of Caragana conferta along with docosyl-3,4 -dihydroxy-trans-cinnamate (2) and tetracosyl-3,4 -dihydroxy-trans-cinnamate (3) isolated for the first time from this species.     

Three new isoflavone glycosides from Tongmai granules

Three new isoflavone glycosides, 3'-methoxydaidzein-7,4'-di-O-β-d-glucopyranoside (1), biochanin A-8-C-β-d-apiofuranosyl-(1?→?6)-O-β-d-glucopyranoside (2), daidzein-7-O-β-d-glucopyranosyl-(1?→?4)-O-β-d-glucopyranoside (3), and a new natural isoflavone glycoside, daidzein-7-O-α-d-glucopyranosyl-(1?→?4)-O-β-d-glucopyranoside (4) were isolated along with 18 known isoflavones from the EtOAc and n-BuOH fractions of the aqueous extraction of Tongmai granules. All the isoflavones were obtained and determined for the first time from Tongmai granules. The structures of these compounds were elucidated by spectral methods. It was confirmed that the compounds 1-4 were originally from Puerariae Lobatae Radix based on HPLC-DAD analysis of the crude drug extract. The isoflavones isolated were tested for their antioxidative activities by measuring the capacities of scavenging the 2,2'-diphenyl-1-picrylhydrazyl radical.     

Two new prenylated isoflavones from Hedysarum multijugum

Chemical investigation on the ethyl acetate extract of the roots of Hedysarum multijugum resulted in the isolation of two new prenylated isoflavonoids: 5, 7, 2′-trihydroxy-4′-methoxy-3′-(γ, γ-dimethylallyl) isoflavone (hedysarimisoflavone A, 1) and 5, 7, 2′-trihydroxy-4′-methoxy-6, 8-di-(γ, γ-dimethylallyl) isoflavone (hedysarimisoflavone B, 2). Their structures were elucidated on the basis of spectroscopic analyses, especially, ¹H and ¹³C NMR spectra in conjunction with their 2D experiments, ¹H-¹H COSY, HMQC, HMBC, and NOESY.     

Increased serum and testicular androgen levels in F1 rats with lifetime exposure to soy isoflavones

The consequences of dietary soy isoflavones on serum and testicular androgen levels were examined in F1 male rats from a multigeneration study investigating the effects of diets varying in isoflavone content. Rats were fed either a soy-free casein based diet (AIN93G) or a diet in which alcohol-washed soy protein replaced casein as the protein source and to which increasing amounts of Novasoy, a commercially available isoflavone supplement were added. Analysis of these diets showed that the isoflavone content in each diet was 0 (diet 1; casein based control), 31.7 (diet 2; alcohol-washed soy-based diet control), 36.1 (diet 3), 74.5 (diet 4), 235.6 (diet 5) and 1046.6 (diet 6) mg total isoflavones/kg pelleted diet. The levels of isoflavones in diet 1 would represent a daily intake level of 0 mg isoflavones, diets 2 and 3 estimate a low soy-containing human diet (e.g. North American), diet 4 would correspond to Asian diets (e.g. Japanese) or adult humans taking isoflavone supplements, diet 5 approximates the isoflavone intake by babies fed soy based infant formula and diet 6 approximates fivefold the intake levels by babies or 10-fold the intake levels of adults consuming high isoflavone containing diets. Serum testosterone (T) from F1 male rats sacrificed on postnatal days (PND) 28, 70, 120, 240 and 360 were low at PND 28 (0.4 ng/ml), increased approximately five to sixfold at PND 70 (2.5-3.0 ng/ml) and thereafter declined to a steady state level of approximately 1 ng/ml by PND 120. However, rats on diets 5 and 6 demonstrated altered serum testosterone profiles such that at days 120, testosterone levels remained significantly elevated at approximately 3 ng/ml (P < 0.05). Serum dihydrotestosterone levels exhibited similar profiles and the levels in PND 120 rats on diet 5 or 6 were also significantly elevated (two to threefold, P < 0.05). The intra-testicular testosterone concentration in rats on diet 5 was also elevated at PND 120 compared with diet 1 (P < 0.05). These findings show that F1 male rats continuously exposed to a mixture of dietary soy isoflavones from conception onwards exhibit altered serum and testicular androgen profiles.     

Microencapsulation of water-soluble isoflavone and physico-chemical property in milk

This study was carried out to investigate the addition of water-soluble isoflavone into milk by means of microencapsulation technique. The yield of microencapsulation, sensory attributes, and capsule stability of water-soluble isoflavone microcapsules in milk were measured. Coating materials used was polyglycerol monostearate (PGMS), and core material was water-soluble isoflavone. The encapsulation yield of water-soluble isoflavone with PGMS was 67.2% when the ratio of coating material to core material was 15:1. The rate of water-soluble isoflavone release from capsules was 18, 19, and 25% when stored at 4, 20, and 30 degrees C for 12 days in milk, respectively. In sensory evaluation, beany flavor and color of microencapsuled water-soluble isoflavone added milk were significantly different from uncapsuled water-soluble isoflavone added milk, however, bitterness was not significantly different. In vitro study, micro-capsules of water-soluble isoflavone in simulated gastric fluid with the range of 3 to 6 pHs were released 3.0-15.0%, however, the capsules in simulated intestinal fluid with pH 7 were released 95.7% for 40 min incubation time. In conclusion, this study provided that PGMS as coating materials was suitable for the microencapsulation of water-soluble isoflavone, and the capsule containing milk was almost not affected with sensory attribute.     

Soy isoflavone intake and estrogen excretion patterns in young women: effect of probiotic administration

BACKGROUND: Soy isoflavones may lower breast cancer risk through altered hepatic estrogen metabolism, leading to increased urinary excretion ratios of 2-hydroxyestrone (20HE1) to 16a-hydroxyestrone (16alphaOHE1). MATERIALS AND METHODS: Urinary excretion of 20HE1/16alphaOHE1 was measured in 36 healthy, pre-menstrual women before and after ingestion of a soy-protein formula containing 120 mg of isoflavone daily for one month. Since isoflavone absorption and metabolism depends on intestinal bacteria, effects of co-administration of Lactobacillus GG (2 x 10(12)) on estrogen ratios and isoflavone excretion were studied. Urinary isoflavone excretion measurements assessed compliance. RESULTS: Soy isoflavone ingestion induced quantitative differences in urinary excretion of estrogen metabolites and isoflavones but failed to alter 20HE1/16alphaOHE1 ratios. Co-administration of Lactobacillus GG with soy reduced excretion of total and individual isoflavones by 40% (p=0.08), without altering 2OHE1/16alphaOHE1 ratios. CONCLUSION: Isoflavone-rich soy protein administration alone, or with probiotic supplement, did not alter urinary excretion of estrogen metabolites in premenopausal women. However, adding concentrated probiotics may alter isoflavone bioavailability.