酸式

4R,5S,6R-5,6-Bis-allyl-6-aldehyde-γ-hexanelactone I-145 was prepared from D-arabinose by six steps. Compound I-145 underwent Mukaiyama-type intramolecular aldolization to produce bicyclooctane I-147 stereospecifically.

我们以D-阿拉伯糖为起始原料，经六步反应，得到(4R，5S，6R)-5， 6-二烯丙氧基-6-醛基-γ-己酸内酯I-145，然后I-145发生分子内的Mukaiyama式aldol缩合反应，完全立体专一性地得到环化中间体I-147。

The present invention relates to compounds of formula wherein R is hydrogen, lower alkyl, lower alkoxy, halogen or lower alkyl substituted by halogen; R is hydrogen or halogen; or R and R are together with the carbon atom to which they are attached -CH=CH-CH=CH-; R is hydrogen, lower alkyl, phenyl optionally substituted by halogen, or is hetaryl, optionally substituted by lower alkyl; R is hydrogen, lower alkyl, phenyl, benzyl, lower alkenyl, lower alkoxy, phenyloxy, benzyloxy, S-lower alkyl, halogen, CN, lower alkyl substituted by halogen or O-lower alkyl substituted by halogen; R is hydrogen or lower alkyl, aryl is phenyl or naphthyl; n is 1, 2 or 3; m is 1 or 2; and pharmaceutically acceptable acid addition salts and tautomeric forms thereof.

本发明涉及式化合物及其可药用的酸加成盐和互变异构形式，其中R 1 是氢、低级烷基、低级烷氧基、卤素或被卤素取代的低级烷基；R是氢或卤素；或R 1 和R与它们连接的碳原子一起是-CH＝CH-CH＝CH-；R 2 是氢、低级烷基、任选被卤素取代的苯基或者是任选被低级烷基取代的杂芳基；R 3 是氢、低级烷基、苯基、苄基、低级链烯基、低级烷氧基、苯氧基、苄氧基、S-低级烷基、卤素、CN、被卤素取代的低级烷基或被卤素取代的O-低级烷基；R 4 是氢或低级烷基，芳基是苯基或萘基；n是1、2或3；m是1或2。

The system adopt new materials and new technology,including such equipment as the following:a stainless and carbon steel-fabricated converter and dice and doughnut-type gas heat exchanger with big-orifice baffles and wavy pipes,anodically protected stainless steel acid coolers and pipes,a heat-pi...

该系统在设计中积极采用新材料、新技术，成功地应用了不锈钢和碳钢相结合转化器、阳极保护不锈钢酸冷却器及管道、热管省煤器、新型大孔板波形管碟环式换热器、DCS控制系统等。2年多的生产运行情况表明，装置运行可靠，技术指标先进，生产控制指标达到或好于设计值，总转化率达99.87%，吸收率达99.99%。

Methods MTT assay,electronic microscopy,flow cytometry and tumor volume assay were used to examine the effect of 23-hydroxyl betulinic acid on B16 melanoma cell line.

应用MTT分析，电镜观察，流式细胞仪，肿瘤体积大小测定等方法，对23-羟基桦木酸诱导黑色素瘤细胞进行检测和观察。

FT-IR spectra show that a bridged bidentate complex acid site was formed.

FT-IR光谱分析结果表明，ST/Al-PILC中SO〓离子与TiO〓形成了桥式双配位的酸中心结构。

And cinnamic aldehyde and cinnamic acid were extracted from cinnamon by MAE using water and ethanol as solvents and were analyzed by HPLC method.

利用聚焦式微波辅助萃取系统，结合HPLC分析，对肉桂中的肉桂醛和肉桂酸进行微波萃取分离和分析，并比较了水及乙醇等溶剂作为萃取溶剂的效果。

We systematically evaluated the effects of test temperatureand storage temperature on platelet aggregation using flow cytometryand impedance aggregometry. Aliquots of citrated whole bloodfrom 27 healthy adult male volunteers were stored at 37°Cand 22°C.

我们用流式细胞计量术和阻抗集合度测定系统地评估了测试温度和存储温度对血小板凝集的影响。27名健康成年男性志愿者的一部分含枸橼酸盐的全血储存在37°C 和22°C 的条件下。

Proteins associated with the membrane and the cytosolic portions of the proteome under different copper ion concentrations were differentially labeled with an acid cleavable isotope-coded affinity tag reagent, and the labeled peptides were separated by two-dimensional chromatography and characterized by electrospray ionization-tandem mass spectrometry.

我们分别将在不同铜离子浓度下的细胞质以及细胞内膜中所有蛋白质标识上酸裂性同位素亲和性标识(acid cleavable isotope-coded affinity tag， cICAT)试剂，用二次元管柱层析将所有标识并酵素水解过的片段分离，并且用电洒式串连质谱(electrospray ionization-tandem mass spectrometry， ESI-MS/MS)以及基因体定序资料库决定蛋白质序列。

Both crystallographically unique Zn atoms exit as an octahedral geometry. The four equatorial positions of Zn1 atom are occupied by the carboxylate-oxygen atoms of the two tartrates, and the two oxygens of the left four carboxylate-oxygen atoms coordinate to two different Zn2 atoms, respectively, forming infinite coordination polymer chains. The left two of the trans equatorial positions of Zn2 atom are completed with two oxygen atoms of two water molecules. The axial positions of both Zn atoms are occupied by the nitrogen atoms from different 4,4'-bipyridine molecules to give a 2D rectangular-grid layers with a cavity dimension of 0.51165(3)nm×1.13896(5) nm. A three dimensional network is formed by the crystallization water chains joined by the carboxylate-oxygen atoms through hydrogen-bonding interactions.

两个晶体学独立的Zn原子均为八面体构型，其中Zn1原子赤道配位点被2个酒石酸根中的4个羧酸根氧螯合配位， 2个酒石酸根中剩下的4个羧酸根氧中的2个分别与2个Zn2原子连接形成无限一维链， Zn2原子的另外2个反式赤道配位点被2个水分子氧占据，同时这两种Zn原子的轴向配位点均被4，4'-联吡啶的氮原子占据，形成具有矩形格子[0.51165(3) nm×1.13896(5) nm]的二维层状结构，游离的2个水分子通过氢键作用形成二聚体，并与酒石酸根中未与Zn配位的羧酸氧连接，把二维层状结构连接成三维网状的超分子结构。

Gambogic acid downregulated the expression of Cyclin D3 and Cyclin E dose and time dependently.

3藤黄酸以剂量依赖式降低细胞周期蛋白Cyclin D3和Cyclin E的表达。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷