The setereoselective preparation ofβ-keto esters using baker's yeast in the presence of rice wine koji

By the addition of rice wine koji, enhancement of the reactivity was observed for the baker＇s yeast reduction of β-keto esters into （S）-β-hydroxy esters with high enantiomeric purity （73-98%）.

Iodine-catalyzed Efficient Synthesis of β-Keto Esters from Aldehydes and Ethyl Diazoacetate Under Solvent-free Conditions

An efficient procedure for the synthesis ofβ-keto esters from the reaction of aldehydes and ethyl diazoacetate catalyzed by iodine at room temperature under solvent-free conditions has been described. The catalytic procedure has the advantages of easily available catalyst, mild reaction conditions, high yields, and easy work-up.

Efficient Syntheses of 2-Substituted Benzimidazoles and Benzoxazoles from β-Keto Esters

An efficient synthetic method was developed to synthesize 2-substituted benzimidazoles and benzo- xazoles with β-keto esters as starting materials under mild reaction conditions, during which other functional groups are bearable from reactants to products.

A New Condensation Reaction of β-Keto-δ-valerolactone with Substituted Aniline

A new condensation reaction of β-keto-δ-valerolactones was developed. The condensation products are composed of a pair of isomers because of the formation ofintramolecular hydrogen bond. Their structures were confirmed by 1HNMR and elemental analysis.

PMA-SiO_2 catalyzed synthesis of β-keto enol ethers

An efficient conversion of β-diketones into corresponding β-keto enol ethers with catalytic amount of PMA-SiO2 has been achieved.

Condensation Products from β-Keto-δ-valerolactones

Unexpected condensation products from β-keto-δ-valerolactones were obtained. Theirstructures were confirmed by 'HNMR spectrum and elemental analysis.

The facile insertion of β-keto sulfones to arynes:The direct preparation of polysubstituted ortho-keto benzyl sulfones

One novel carbon-carbon bond insertion reaction of arynes has been developed. By this reaction β-keto sulfones can insert the triple bond of arynes to prepare polysubstituted ortho-keto benzyl sulfones.

乳香提取物调控Wnt/β-catenin信号通路抑制结直肠癌细胞侵袭转移的作用机制研究

目的研究乳香提取物对人结肠癌细胞HCT-116增殖和侵袭转移的影响及可能的作用机制。方法体外培养人结肠癌细胞珠HCT-116,使用不同浓度乳香提取物乙酰基-11-酮基-β-乳香酸(AKBA)分别作用于细胞相同时间后,以CCK-8实验、Transwell细胞侵袭实验、划痕实验检测其对细胞增殖和侵袭转移的影响,以Western blotting、荧光定量PCR等方法探究其对细胞侵袭转移相关蛋白、mRNA表达的影响。结果AKBA可抑制人结肠癌细胞HCT-116的增殖、迁移能力,且呈剂量依赖(P<0.05);AKBA可抑制C-Myc、β-catenin的蛋白和mRNA表达,且呈剂量依赖(P<0.05)。结论AKBA可以抑制人结肠癌细胞HCT-116的增殖和迁移,诱导细胞凋亡。这可能与其调控Wnt/β-catenin信号通路相关。

Photocatalytic Aerobic Oxysulfonylation of Alkynes to Access β-Keto Sulfones Catalyzed by OVs-N-Nb_(2)O_(5)

Herein,we report a novel heterogeneous photocatalyst for radical-mediated oxidative oxysulfonylation of alkynes toβ-keto sulfones under environmentally benign conditions.The oxygen vacancy-rich semiconductor Nb2O5(labeled as OVs-N-Nb_(2)O_(5))could efficiently catalyze a wide range of alkynes,especially for those bearing electron-deficient substituents or internal alkynes,to their correspondingβ-keto sulfones in good to high yields with good tolerance of diverse functional groups under visible-light illumination.The late-stage modification of steroidal compounds and synthesis of bioactive molecules were also achieved via this procedure,highlighting its potential for practical applications.Meanwhile,the photocatalyst OVs-N-Nb_(2)O_(5) showed outstanding catalytic stability for successive recycles without appreciable loss in activity and selectivity.The critical role of oxygen vacancies on improving reaction activity and selectivity was clearly disclosed via control experiments and theoretical calculation.

Substituent, Temperature and Solvent Effects on the Keto-Enol EQUILIBRIUM in <i>&beta;</i>-Ketoamides: A Nuclear Magnetic Resonance Study

Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds.

β环糊精包合血竭对血栓形成和TXB_2/6-Keto-PGF_(1α)水平的影响

目的探讨血竭β环糊精包合血竭对血栓形成作用机制.方法电刺激大鼠颈动脉血栓形成方法评价包合-PGF1α水平.结果包合血竭对电刺激大鼠颈动脉引起的血栓有明显的对抗作用,体内外均显著抑制花生四烯酸(AA)诱导的家兔血小板聚集,并降低家兔血浆TXB2含量,升高6-Keto--PGF1α水平.结论包合血竭抗血栓形成作用与抑制花生四烯酸(AA)代谢有关.

Acetyl-11-keto-β-boswellic acid extracted from Boswellia serrata promotes Schwann cell proliferation and sciatic nerve function recovery

Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid （AKBA） is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may promote regeneration of injured sciatic nerve. To address this hypothesis, we established a rat model of sciatic nerve injury using a nerve clamping method. Rats were administered AKBA once every 2 days at doses of 1.5, 3, and 6 mg/kg by intraperitoneal injection for 30 days from the 1st day after injury. Sciatic nerve function was evaluated using the sciatic functional index. Degree of muscle atrophy was measured using the triceps surae muscle Cuadros index.Neuropathological changes were observed by hematoxylin-eosin staining. Western blot analysis was used to detect expression of phospho-extracellular signal-regulated kinase 1 and 2 （p-ERK1/2） in injured nerve. S100 immunoreactivity in injured nerve was detected by immunohistochemistry. In vivo experiments showed that 3 and 6 mg/kg AKBA significantly increased sciatic nerve index, Cuadros index of triceps muscle, p-ERK1/2 expression, and S100 immunoreactivity in injured sciatic nerve of sciatic nerve injury model rats. Furthermore,for in vitro experiments, Schwann cells were treated with AKBA at 0–20 μg/mL. Proliferation of Schwann cells was detected by Cell Counting Kit-8 colorimetry assay. The results showed that 2 μg/mL AKBA is the optimal therapeutic concentration. In addition, ERK phosphorylation levels increased following 2 μg/mL AKBA treatment. In the presence of the ERK1/2 inhibitor, PD98059 （2.5 μL/mL）, the AKBA-induced increase in p-ERK1/2 protein expression was partially abrogated. In conclusion, our study shows that AKBA promotes peripheral nerve regeneration with ERK protein phosphorylation playing a key role in this process.

Ferric chloride-catalyzed decarboxylative alkylation of β-keto acids with benzylic alcohols

β-Keto acids are unstable to heat,acids,and bases,and have rarely been employed as carbon nucleophiles for the formation of carbon-carbon bonds.In this context,an efficient decarboxylative alkylation reaction of β-keto acids with benzylic alcohols has been developed,for the first time,through sequential cleavage of carbon-oxygen and carbon-carbon bonds.In the presence of 10 mol% of ferric chloride,a range of β-keto acids smoothly undergo decarboxylative alkylation with benzylic alcohols to give structurally diverse unsymmetric ketones in moderate to excellent yields and with extremely high regioselectivity.Preliminary mechanistic studies indicate that the reaction proceeds through an SN1 alkylation followed by decarboxylation.

Selective α-Bromination of β-Keto Esters in Reusable PEG-400 under Mild and Catalyst-free Conditions

为 -bromo--keto 酉旨的合成的一个有效 bromination 协议被开发了。在 PEG-400 (poly (乙烯 glycol-400 )) ，许多 -keto 酉旨在房间温度与 NBS (N-bromosuccinimide ) 被对待有选择地在优秀收益负担得起相应 -monobromination 产品。反应在温和、环境地良性、没有催化剂的条件下面被进行，是引人注目的。

Decarboxylative Alkylation of β-Keto Acids with Isochromans under Oxidative Conditions

有 isochromans 的 -keto 酸的崭新的 decarboxylative 完化反应在氧化条件下面被开发了。-keto 酸的一个范围顺利面对 2,2,6,6-tetramethylpiperdine-1-oxoammonium hexafluorophosphate 与 isochromans 经历 decarboxylative 完化交上在结构上多样的 1-acylmethylisochromans 对有极其高的 regioselectivity 的优秀收益中等。

Pyruvate-Dependent Changes in Neutrophil Amino- and Alpha-Keto Acid Profiles or Immunity: Which Mechanisms Are Involved?

High current findings indicate that a substitution with pyruvate can lead to significant alterations or even improvement in neutrophil immunonutrition. However, it is still unknown which intra-cellular pathways might be involved here. Hence, in this study, we investigated whether preincu-bation with an inhibitor of ·NO-synthase (L-NAME), an ·NO donor (SNAP), an analogue of taurine (beta-alanine), an inhibitor of ornithine-decarboxylase (DFMO) as well as a glutamine-analogue (DON), is able to alter the intragranulocytic metabolic response to pyruvate, here for example studied for neutrophil intracellular amino- and α-keto acid concentrations or important neutrophil immune functions [released myeloperoxidase (MPO), the formation of superoxide anions O2- and hydrogen peroxide (H2O2)]. In summary, the interesting first results presented here showed, that any damage of specific metabolic pathways or mechanisms, which seem directly or indirectly to be involved in relevant pyruvate dependent granulocytic nutrient content or specific cellular tasks, could lead to therapeutically desired, but also to unexpected or even fatal consequences for the affected cells. We therefore continue to believe that pyruvate, irrespective of which exact biochemical mechanisms were involved, in neutrophils may satisfy the substantial metabolic demands for a potent intracellular nutrient.

小金胶囊的质量标准提升研究

目的 提升小金胶囊的质量标准。方法 采用HPLC法测定醋乳香中11-羰基-β-乙酰乳香酸的含量。根据15批样品的GC图谱,采用国家药典委员会“中药色谱指纹图谱相似度评价系统(2012年版)”进行相似度评价和共有峰的确定。按照中国药典方法检测本品中重金属铅、镉、砷、汞、铜的含量。结果 11-羰基-β-乙酰乳香酸的线性范围为13.346~166.824μg·mL^(-1)(r=0.999 8),方法准确度好,平均回收率为100.76%,RSD为1.52%(n=6),专属性、重复性均符合要求。建立了小金胶囊的GC指纹图谱检测方法,标定出11个共有峰,15批样品的相似度均大于0.870,具有良好的相似性。15批样品中的铅、镉、砷、汞、铜含量均符合中国药典参考限度。结论本研究所建立的GC指纹图谱检测方法和11-羰基-β-乙酰乳香酸的HPLC含量测定方法,以及对重金属的检查,可作为小金胶囊的质量控制项,用于提升小金胶囊的质量控制标准。

高效液相色谱法测定筋骨痛消液中11-羰基-β-乙酰乳香酸和川续断皂苷Ⅵ的含量

目的:建立筋骨痛消液中11-羰基-β-乙酰乳香酸和川续断皂苷Ⅵ的含量测定方法。方法:采用高效液相色谱法测定筋骨痛消液中11-羰基-β-乙酰乳香酸和川续断皂苷Ⅵ的含量,色谱柱为Agilent Eclipse Plus C18(4.60 mm×250 mm, 5μm),以0.05%磷酸-乙腈(20∶80)为流动相在254 nm波长下测定11-羰基-β-乙酰乳香酸;以水-乙腈(70∶30)为流动相在212 nm波长下测定川续断皂苷Ⅵ,随机挑选10批次筋骨痛消液,并对其含有的11-羰基-β-乙酰乳香酸和川续断皂苷Ⅵ分别进行测定。结果:11-羰基-β-乙酰乳香酸在0.010 2~1.020 5 mg·mL^(-1)(r=0.999 9)线性关系良好,平均加样回收率为99.11%,RSD为1.50%(n=9),10批次样品中的平均含量为1.435 3 mg·mL^(-1);川续断皂苷Ⅵ在0.010 2~1.020 0 mg·mL^(-1)(r=0.999 9)线性关系良好,平均加样回收率为99.21%,RSD为2.17%(n=9),10批次样品中的平均含量为0.816 3 mg·mL^(-1)。结论:该方法结果准确,灵敏度高,重复性好,可用于筋骨痛消液的质量控制。

基于熵权法结合Box-Behnken响应面优化筋骨痛消液的制剂醇提工艺

目的优化筋骨痛消液的制剂工艺。方法采用熵权法结合Box-Behnken响应面法对筋骨痛消液中乳香、续断、龙血竭与红花及大黄与薄荷的醇提工艺进行优化。结果11-羰基-β-乙酰乳香酸含量与乳香醇提液浸膏得率权重系数分别为0.5166,0.4834;川续断皂苷Ⅵ含量与续断醇提液浸膏得率权重系数分别为0.4790、0.5210。乳香、续断、龙血竭与红花、大黄与薄荷最优醇提条件乙醇浓度分别为95%,55%,80%,60%;加醇倍量分别为5倍,5倍,7倍,8倍;浸泡时间分别为48 h,72 h,24 h,72 h。结论通过熵权法结合响应面法设计优化筋骨痛消液的制剂提取工艺,为筋骨痛消液制剂质量提升及质量保证提供科学依据。