Synthesis and Crystal Structure of 2-Amino-4- chloro-5-（4-methylbenzyl）-6-methylpyrimidine

The title compound 2-amino-4-chloro-5-(4-methylbenzyl)-6-methylpyrimidine (C26H28Cl2N6, Mr = 495.44) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 14.892(7), b = 6.129(3), c = 14.889(7) , β = 109.795(8)°, V = 1278.7(10) 3, Z = 2, F(000) = 520, Dc = 1.287 g/cm3, μ = 0.280 mm-1, the final R = 0.0577 and wR = 0.1589 for 1357 observed reflections with I > 2σ(I). A total of 6091 reflections were collected, of which 2257 were independent (Rint = 0.033). The X-ray analysis reveals that the chlorine atom and methyl of the title compound are disordered.     

1－甲基－2－甲氧羰基－4－氨基吡咯盐酸盐的合成

以1－甲基吡咯为原料，通过酰化、硝化、酯化、还原、成盐等五步反应，合 成得到1－甲基－2－甲氧羰基－4－氨基吡咯盐酸盐，总产率20％左右。该法具有 原料便宜易得、操作简单、产物易于分离提纯等优点，有利于该化合物的大量制备 和应用。     

通过三乙基铝促进的a-羟基环氧化合物的重排还原反应合成Madindoline母核片断——全取代环戊烯二酮单元

The fully substituted cyclopentenedione core of madindoline A （1） and B （2） as potent and selective inhibitor of IL-6 has been synthesized efficiently. The quaternary carbon center C-2＇ was constructed on the basis of a newly developed AIEt3-promoted tandem reductive rearrangement of α-hydroxy epoxides.     

西松烷型二萜内酯的全合成进展

按照内酯环的大小综述了西松烷二萜的合成方法。     

Biocatalytic process intensification via efficient biocatalyst immobilization,miniaturization, and process integration

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数码成像比色法测定水样中的总磷

在酸性介质中,磷酸二氢钾与钼酸铵、酒石酸锑钾及抗坏血酸作用,生成蓝色的络合物。随着磷酸二氢钾浓度的增加,溶液颜色加深,其数码成像的RGB值亦随着磷酸二氢钾浓度的增加而增加,由此建立数码成像比色法(DIC)测定水样中总磷的新方法。考察了DIC法的影响因素和最佳反应条件。与钼酸铵分光光度法对照,该方法简单,快速。用于实际水样的测定,相对标准偏差为1.8%~3.4%,回收率为99.7%~102.5%,结果与分光度法一致。     

STUDY ON THE PROPERTIES OF BLEND OF NATURAL RUBBER LATEX/METHYL METHACRYLATE GRAFTED RUBBER LATEX BY GAMMA RADIATION

Natural rubber latex(NRL)and methyl methacrylate(MMA)grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from Co-60 source at room temperature.The tensile properties, swelling ratio and permanent set were measured.The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy.Modulus increases from 6.99 MPa to 9.87 MPa for an increase in proportion of MMA grafted rubber from 40% to 60% in the blend at similar absorbed dose.Elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA grafted rubber content in the blends.The decreasing trend of permanent set is high up to 5 kGy absorbed dose,and beyond that dose,it becomes almost flat.     

Radiation formation of polymeric nanogels

An alternative method of synthesis of polymeric nanogels is proposed, based not on polymerization, but on intramolecular crosslinking of polymer chains, initiated by pulse irradiation in dilute aqueous solutions. Kinetic data show that for many water-soluble polymers irradiation under these conditions result in intramolecular crosslinking. Preliminary product studies on poly(vinyl alcohol) indicate that in fact internally crosslinked macromolecules can be obtained by this technique.     

A study for quality evaluation of Taxilli Herba from different hosts based on fingerprint-activity relationship modeling and multivariate statistical analysis

In this study, a fingerprint-activity relationship modeling between chemical fingerprints and antirheumatic activity was established, and multivariate statistical analysis was used to evaluate the quality of Taxilli Herba (TH) from different hosts. Characteristic fingerprints of 20 batches of TH samples were generated by high-performance liquid chromatography coupled with triple quadrupole-time of flight tandem mass spectrometry (HPLC-Triple TOF-MS/MS), and the similarity analysis was calculated based on thirteen common characteristic peaks by hierarchical clustering analysis (HCA). Subsequently, nine efficacy markers were discovered by combining fingerprints and antirheumatic activity through grey correlation analysis (GCA) and bivariate correlation analysis (BCA). Meanwhile, the content of 5 constituents in 9 markers was determined by high-performance liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry (HPLC-QTRAP-MS/MS). The comprehensive quality of TH was assessed using multivariate statistical analysis, including principal components analysis (PCA) and technique for order preference by similarity to ideal solution (TOPSIS). The results showed that a high dose of TH extract could markedly ameliorate arthritis damage compared to other doses, with flavonoids playing an important role in the antirheumatic activity. The comprehensive quality of samples from Morus alba L. (SS) was superior to those from Liquidambar formosana Hance (FXS). The present study will demonstrate the markers associated with efficacy, and provide an applicable strategy for more comprehensive quality control and evaluation of TH.