Diacylated Triterpenoid Saponin from Silene szechuensis

A new triterpenoid saponin, named silenoside, with sugar chains esterified by two different acyl groups was isolated from Silene szechuensis. Its structure was elucidated by chemical and spectral methods.

Inhibition of DNA-Topoisomerase I by Acylated Triterpene Saponins from Pittosporum angustifolium Lodd.

Previous phytochemical investigation of the leaves and seeds of Pittosporum angustifolium Lodd.led to the isolation and structural elucidation of polyphenols and triterpene saponins.Evaluation for cytotoxicity of isolated saponins revealed that the predominant structural feature for a cytotoxic activity are acyl substituents at the oleanane aglycon backbone.The present work reports the results of a screening of 10 selected acylated saponins for their potential to inhibit the human DNA-topoisomerase I,giving rise to IC50 values in a range of 2.8-46.5 lM.To clarify the mode of observed cytotoxic action and,moreover,to distinguish from a pure surfactant effect which is commonly accompanied with saponins,these results indicate an involvement of the topoisomerase I and its role as a possible target structure for a cytotoxic activity.In addition,computational predictions of the fitting of saponins to the topoisomerase I-DNA complex,indicate a similar binding mode to that of clinically used topoisomerase I inhibitors.Graphical Abstract Ten acylated triterpene saponins from Pittosporum angustifolium were investigated for their potential to inhibit the human DNA-topoisomerase I and computational predictions of the fitting of saponins to the topoisomerase I-DNA complex were carried out.

Preparation and Characterization of Acylated Chitosan

Fully acylated chitosan and N, N-diacyl chitosan were prepared. The products were characterized by elemental analysis, FTIR and 1H NMR. The experimental results indicate that the average degree of acylation depends on the volume ratio of pyridine to chloroform in the reaction medium, the chain length of the acylation agent used, and the molecular weight of chitosan raw materials. The XRD measurements were carried out for pure chitosan, fully acylated chitosan and N, N-diacyl chitosan to verify the crystallinity change caused by the acylation.

A New Acylated Anthocyanin from the Red Flowers of Camellia hongkongensis and Characterization of Anthocyanins in the Section Camellia Species

Twelve anthocyanins （1-12） were isolated from the red flowers of Camellia hongkongensis Seem. by chromatography using open columns. Their structures were elucidated on the basis of spectroscopic analyses, that is, proton-nuclear magnetic resonance, carbon 13-nuclear magnetic resonance, heteronuclear multiple quantum correlation, heteronuclear multiple bond correlation, high resolution electrospray ionization mass and ultraviolet visible spectroscopies. Out of these anthocyanins, a novel acylated anthocyanin, cyanidin 3-O-（6-O-（Z）-p-coumaroyl）-β-galactopyranoside （6）, two known acylated anthocyanins, cyanidin 3-O-（6-O-（E）-p-coumaroyl）-β-galactopyranoside （7） and cyanidin 3-O-（6-O-（E）-caffeoyl）-^- galactopyranoside （8）, and three known delphinidin glycosides （10-12） were for the first time isolated from the genus Camellia. Furthermore, pigment components in C. japonica L., C. chekiangoleosa Hu and C. semiserrata Chi were studied. The results indicated that the distribution of anthocyanins was differed among these species. Delphinidin glycoside was only detected in the flowers of C. hongkongensis, which is a special and important species in the section Camellia. Based on the characterization of anthocyanins in the section Camellia species, there is a close relationship among these species, and C. hongkongensis might be an important parent for creating new cultivars with bluish flower color.

The enzymatic biosynthesis of acylated steroidal glycosides and their cytotoxic activity

Herein we describe the discovery and functional characterization of a steroidal glycosyltransferase(SGT) from Ornithogalum saundersiae and a steroidal glycoside acyltransferase(SGA) from Escherichia coli and their application in the biosynthesis of acylated steroidal glycosides(ASGs). Initially,an SGT gene, designated as OsSGT1, was isolated from O. saundersiae. OsSGT1-containing cell free extract was then used as the biocatalyst to react with 49 structurally diverse drug-like compounds. The recombinant OsSGT1 was shown to be active against both 3β-and 17β-hydroxyl steroids. Unexpectedly,in an effort to identify OsSGT1, we found the bacteria lacA gene in lac operon actually encoded an SGA,specifically catalyzing the acetylations of sugar moieties of steroid 17β-glucosides. Finally, a novel enzymatic two-step synthesis of two ASGs, acetylated testosterone-17-O-β-glucosides(AT-17β-Gs) and acetylated estradiol-17-O-β-glucosides(AE-17β-Gs), from the abundantly available free steroids using OsSGT1 and EcSGA1 as the biocatalysts was developed. The two-step process is characterized by EcSGA1-catalyzed regioselective acylations of all hydroxyl groups on the sugar unit of unprotected steroidal glycosides(SGs) in the late stage, thereby significantly streamlining the synthetic route towards ASGs and thus forming four monoacylates. The improved cytotoxic activities of 30-acetylated testosterone17-O-β-glucoside towards seven human tumor cell lines were thus observable.

Low expression of fatty acid oxidation related gene ACADM indicates poor prognosis of renal clear cell carcinoma and is related to tumor immune infltration

This research aims to identify the key fatty acid beta-oxidation(FAO)genes that are altered in kidney renal clear cell carcinoma(KIRC)and to analyze the role of these genes in KIRC The Gene Expression Omnibus(GEO)and FAO datasets were used to identify these key genes.Wilcoxon rank sum test was used to assess the levels of acyl-CoA dehydrogenase medium chain(ACADM)between KIRC and non cancer samples.The logistic regression and Wilcoxon rank sum test were used to explore the association between ACADM and clinical features.The diagnostic performance of ACADM for KIRC was asessed using a diagnostic receiver operating ch aracteristic(ROC)curve.The co-expressed genes of ACADM were identifed in LinkedOmics database,and their function and pathway enrichment were analyzed.The correlation between ACADM expression level and immune infitration was analyzed by Gene Set Variation Analysis(GSVA)method Additionally,the proliferation,migration,and invasion abilities of KIRC cells were assessed after overexpressing ACADM.Following differential analysis and intersection,we identifed six hub genes,induding ACADM.We found that the expression level of ACADM was decreased in KIRC tissues and had a better diagnostic efect(AUC=0.916).Survival analysis suggested that patients with decreased ACADM expression had a worse prognosis.According to correlation analysis,a variety of dinical features were associated with the expression level of ACADML By analyzing the infiltration level of immune cells,we found that ACADM may be related to the enrichment of immune cells.Finally,ACADM overexpression inhibited proliferation,migration,and invasion of KIRC cells.In conclusion,our findings suggest that reduced ACADM expression in KIRC patients is indicative of poor prognosis.These results imply that ACADM may be a diagnostic and prognostic marker for individuals with KIRC,offering a reference for dinicians in diagnosis and treatment.

Synthesis of Long Chain Fatty Acids Acylated Coumarin Glycoside Esters with Lipase as Catalyst

A series of novel coumarin glycoside esters（1-9） was synthesized through the acylation reaction of 4-methylcoumarin-7-O-β-D-glucoside（11） with different long chain fatty acids catalyzed by lipase in organic medium. The acylation occurred regioselectively at the 6＇-OH of glycosyl moiety. The enzymatic synthesis was optimized to achieve 54%-70% yield using immobilized lipase（Novozym 435, 10 mg/mL） as catalyst and acetone and pyri- dine（9：1, volume ratio, water content〈1%） as solvent with an acyl donor/coumarin glycoside molar ratio of 10：1 at a temperature of 40--50 ℃ for 96 h. All the synthesized compounds were confirmed.

Regioselective Acylation of 2＇- or 3＇-Hydroxyl Group in Salicin： Hemisynthesis of Acylated Salicins

Salicin-based phenolic glycosides（PGs） are important defensive substances against herbivore feeding and have good bioactivities. In this work, a novel approach for the synthesis of salicin-based PGs has been developed, by which PGs of 2＇-O-acetylsaliein（5a）, 3＇-O-acetylsalicin（gb） and 3＇-O-benzoylsalicin（Sd） were hemisynthesized. The effects of acylation reagent, solvent and temperature on the regioselective acylation of 2＇- or 3＇-hydroxyl groups of salicin mediated by dibutyltin oxide were investigated. The optimal conditions under which the best regioselectivity reached for 5a-5d were discovered, respectively. Moreover, a tentative tin-oxygen coordination mechanism was put forward to explain the different regioselectivities shown under different conditions.

interrelationships between ghrelin, insulin and glucose homeostasis: physiological relevance

Ghrelin is a 28 amino acid peptide mainly derived from the oxyntic gland of the stomach. Both acylated(AG) and unacylated(UAG) forms of ghrelin are found in the circulation. Initially, AG was considered as the only bioactive form of ghrelin. However, recent advances indicate that both AG and UAG exert distinct and common effects in organisms. Soon after its discovery, ghrelin was shown to promote appetite and adiposity in animal and human models. In response to these anabolic effects, an impressive number of elements have suggested the influence of ghrelin on the regulation of metabolic functions and the development of obesityrelated disorders. However, due to the complexity ofits biochemical nature and the physiological processes it governs, some of the effects of ghrelin are still debated in the literature. Evidence suggests that ghrelin influences glucose homeostasis through the modulation of insulin secretion and insulin receptor signaling. On the other hand, insulin was also shown to influence circulating levels of ghrelin. Here, we review the relationship between ghrelin and insulin and we describe the impact of this interaction on the modulation of glucose homeostasis.

Hrd1转基因小鼠的构建与验证

背景 内质网应激在糖尿病视网膜病变（DR）中发挥着重要作用.羟甲基戊二酰辅酶A还原酶降解蛋白1（Hrd1,又名Syvn1）作为一种内质网相关蛋白降解（ERAD）途径中的核心蛋白,能够减少内质网应激. 目的 构建Hrd1高表达小鼠,为今后研究Hrd1在DR中的作用提供动物模型. 方法 构建Hrd1系统表达重组质粒,酶切、测序后显微注射3 p1到685枚C57BL/6小鼠受精卵中,移植到代孕母鼠,得到Hrd1转基因小鼠.利用鼠尾PCR检测法鉴定F0代小鼠的基因型.得到Hrd1基因检测阳性鼠后,使其分别与野生型鼠杂交,得到F1代Hrd1转基因小鼠,取鼠尾组织,用PCR检测法再次鉴定F1代小鼠基因型. 结果 成功构建了Hrd1重组载体,重组质粒pRP.ExBi-EF1 a-Syvn1-IRES-eGFP的全序列测定结果显示,cDNA序列均正确.接受了Hrd1-pcDNA显微注射的685枚受精卵中成活598枚.将存活的受精卵移植到代孕母鼠后共产子鼠41只,获F0代子鼠8只,生理活动均良好.PCR电泳显示339 bp处阳性条带,该基因型可以传递到子代F1.结论 成功构建了Hrd1转基因小鼠.

Comparison of total/active ghrelin levels in primary open angle glaucoma,pseudoexfoliation glaucoma and pseudoexfoliation syndrome

AIM：To investigate the levels of ghrelin（Gh）,acylated ghrelin（AGh） and AGh/Gh ratio in the humor aqueous（HA） of cases with pseudoexfoliation syndrome（PXS）,pseudoexfoliation glaucoma（PXG）,primary open angle glaucoma（POAG） and to compare these with control subjects.METHODS：A prospective examination was made of the total Gh,and AGh levels in HA of 67 patients undergoing cataract surgery.Patients were divided into 4 groups.HA samples were aspirated at the beginning of the surgery,stored at -70℃.Gh and AGh quantification was performed with ELISA kits and the AGh/total-Gh ratios were calculated.ANOVA,Kruskal-Wallis,Chi-square and post-hoc tests were used for statistical analysis.RESULTS：Total Gh levels in HA were 189.2±45.6 pg/mL in the control group,199.2±32.9 pg/mL in PXS,180.6±20.9 pg/mL in PXG and 176.8±21.4 pg/mL in POAG groups（P〉0.05）.AGh levels in HA were 23.09±5.01 pg/mL in the control group,24.13±5.22 pg/mL in PXS,22.29±1.55 pg/m L in PXG and 19.69±2.93 pg/mL in POAG groups（P〉0.05）.The ratio of AGh/Gh was 10.3%±2.34% in the control group,13.03%±2.58% in PXS,12.3%±1.54% in PXG and 11.79%±1.41% in POAG groups（P=0.044）.The difference between the PXS and control groups was significant（P=0.03）.CONCLUSION：In spite of statistically insignificant results,the HA total Gh levels were lower than those of the control subjects but not parallel with the AGh levels in glaucoma patients.The relative increase in the AGh/Gh ratio in glaucoma cases supports the view that proportional increases of AGh might play a role in the pathogenesis of glaucoma.

Two new C-glycosylflavones from the leaves of Iris lactea var. chinensis

Two new acylated C-glycosylflavones were isolated from the leaves of Iris lactea var. chinensis, and their structures were elucidated on the basis of extensive NMR experiments and mass spectrometry methods and were assigned as 5-hydroxy-4＇- methoxyflavone-7-O-（β-D-2＇＇＇＇4＇＇＇＇-diacetylrhamnopyranosyl）-6-C-[ O-（α-L-6＇＇＇-acetyl-glucpyranosyl）-1→2-β-D-glucopyrano- side] （irislactin A） and 5-hydroxy-4＇,7-dimethoxyflavone-6-C-[O-（α-L-2＇＇＇,3＇＇＇-diacetylrhanmo-pyranosyl）-1→ 2-β-D-glucopyranoside] （irislactin B）.

法国公司推出防治母猪尿道和生殖道疾病的营养方案

母猪尿道和生殖系统的疾病是生猪饲养当中经常发生的问题，不管从经济上还是技术上，都会导致一些饲养者无法忽视的后果。在法国，根据饲养的类型不同，这类疾病所导致的损失每百头母猪高达一千五百到两千欧元。因病症出现很晚，这类疾病又很难检测，因此提高尿液的酸性程度，能够起到限制细菌生长的作用，是一种有效的预防措施。

Anti-oxidant and anti-inflammatory effects of hydrogenrich water alleviate ethanol-induced fatty liver in mice

AIM To investigate the effects of hydrogen-rich water(HRW) treatment on prevention of ethanol(Et OH)-induced early fatty liver in mice.METHODS In vitro reduction of hydrogen peroxide by HRW was determined with a chemiluminescence system. Female mice were randomly divided into five groups: control,Et OH,Et OH + silymarin,Et OH + HRW and Et OH + silymarin + HRW. Each group was fed a Lieber-De Carli liquid diet containing Et OH or isocaloric maltose dextrin(control diet). Silymarin was used as a positive control to compare HRW efficacy against chronic Et OH-induced hepatotoxicity. HRW was freshly prepared and given at a dosage of 1.2 m L/mouse trice daily. Blood and liver tissue were collected after chronic-binge liquid-diet feeding for 12 wk.RESULTS The in vitro study showed that HRW directly scavenged hydrogen peroxide. The in vivo study showed that HRW increased expression of acyl ghrelin,which was correlated with food intake. HRW treatment significantly reduced Et OH-induced increases in serum alanine aminotransferase,aspartate aminotransferase,triglycerol and total cholesterol levels,hepatic lipid accumulation and inflammatory cytokines,including tumor necrosis factor-alpha(TNF-α) and interleukin(IL)-6. HRW attenuated malondialdehyde level,restored glutathione depletion and increased superoxide dismutase,glutathione peroxidase and catalase activities in the liver. Moreover,HRW reduced TNF-α and IL-6 levels but increased IL-10 and IL-22 levels.CONCLUSION HRW protects against chronic Et OH-induced liver injury,possibly by inducing acyl ghrelin to suppress the pro-inflammatory cytokines TNF-α and IL-6 and induce IL-10 and IL-22,thus activating antioxidant enzymes against oxidative stress.

一种高效简易的聚(4-乙烯基三溴化吡啶)催化乙醇合成乙酸盐的方法(英文)

Poly(4-vinylpyridinium tribromide) is an efficient catalyst for the conversion of various alcohols to their corresponding acetate derivatives with acetic anhydride.This method has some advantages such as mild reaction conditions,good to excellent yields,and ease of work-up.

Synthesis, Crystal Structure, Docking and Antifungal Activity of a New Pyrazole Acylurea Compound

The title compound N-（（3,5-dimethylphenyl）carbamoyl）-1-methyl-3-（trifluoromethyl）-1 H-pyrazole-4-carboxamide（C（15）H（15）F3N4O2） was synthesized, and its structure was confirmed by 1 H NMR, H RMS and X-ray diffraction. It crystallizes in the triclinic system, space group P1 with a = 11.7147（5）, b = 11.7935（5）, c = 13.6620（5） A, α = 69.755（7）°, β = 66.182（6）°, γ = 72.100（7）°, Dc = 1.423 g/cm^3, Z = 4, V = 1588.88（11） A^3, the final R = 0.0347 and wR = 0.1005 for 7171 observed reflections with I 〉 2σ（I）. The preliminary biological test showed that the title compound has antifungal activities against Fusarium oxysporum, Pseudomonas syringae, Corynespora mazei and Botrytis cinerea at 100 μg/mL as 5.19%, 53.50%, 88.55% and 70.62%, respectively. The docking results indicated the hydrogen bonds formed between the compound and SHD.

Regioselective enzymatic acylation of troxerutin in nonaqueous medium

A series of monosubstituted troxerutin esters have been synthesized by enzyme-catalyzed regioselective acylation of troxerutin in nonaqueous medium.Using divinyl dicarboxylates(CH_2=CH-OOC-(CH_2)_n-COO-CH=CH_2,n = 2,3,4,7,8,11) featuring different chain length as acyl donors and alkaline protease from Bacillus subtilis as catalyst,troxerutin was regioselective acylated at B ethoxyl group.The results indicated that the regioselectivity of the enzyme-catalyzed acylation was not affected by the chain length o...

Synthesis and Thermal Crosslinking Behavior of Poly(aryl ether ketone)s Containing 1,4-Naphthalene Moieties

A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene(compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride(compound 1) was prepared by using the acyl chlorization reaction of 1,4-naphthalenedicarboxylic acid with thionyl chloride. The Friedel-Crafts acylation of compound 1 with fluorobenzene afforded compound 2 in a 80% yield. The polycondensation of compound 2 with various bisphenols in tetramethylene sulfone(TMS) in the presence of excess potassium carbonate as a condensation reagent was carried out at 210 ℃ to quantitatively afford the corresponding poly(aryl ether ketone)s(compounds 3_8) containing 1,4-naphthalene moieties. Thermal analyses showed that the polymers have T g values ranging from 496 to 500 K and are thermally stable in air with initial mass loss above 500 ℃. These novel polymers exhibited an excellent solubility in organic solvents including NMP, DMAc, and chloroform, etc. In addition, the glass transition temperatures of these polymers increased and the polymers became insoluble in chloroform after treated at 260 ℃, indicating the occurrence of a thermal crosslinking reaction.

Synthesis, Crystal Structure and Fungicidal Activity of 3-(Difluoromethyl)-1-methyl-N-((2-(trifluoromethyl)phenyl) carbamoyl)-1H-pyrazole-4-carboxamide

The title compound 3-(difluoromethyl)-1-methyl-N-((2-(trifluoromethyl)phenyl)-carbamoyl)-1 H-pyrazole-4-carboxamide(C14 H11 F5 N4 O2) was synthesized, and its structure was confirmed by 1 H NMR, H RMS and X-ray diffraction. It crystallizes in monoclinic system, space group P21/n with a = 6.994(3), b = 13.860(6), c = 15.308(7)A,β= 97.632(6)°, V = 1470.8(11) A^3,Z = 4, the final R = 0.0692 and wR = 0.2108 for 3989 observed reflections with Ⅰ> 2σ(Ⅰ). The preliminary biological test shows that the title compound has moderate fungicidal activities against Pseudomonas syringae.

A Rapid and Convenient Synthesis of Acylals from Aldehydes and Acetic Anhydrides Catalyzed by SnCl_4/SiO_2

A variety of aldehydes were converted into acylals in excellent yields with acetic anhydride in the presence of a catalytic amount of tin (IV) chloride supported on silica gel at room temperature.