Time Related Influence of α-Mercapto-β-(2-Furyl) Acrylic Acid (MFA) in Cadmium Toxicity

The effect of a-mercapto-β-(2-furyl) acrylic acid (MFA, 200 mg/kg, oral) administered 30 min or 24 h post cadmium (1 mg/kg, i.p.) exposure on cadmium toxicity, was investigated in rats. The Cd induced hepatic metallothionein was reduced by MFA treatment parallel to the depletion of hepatic Cd. However, in renal tissue,MFA caused only redistribution of metal from the paniculate to the soluble fraction. Hepatic and renal Zn and renal Cu were significantly increased on Cd exposure. MFA therapy, however, lowered the hepatic Zn and increased the renal Cu levels. The action of MFA appears to be via metal chelation rather than by MT induction.

Determination of Trace Amounts of Zinc, Iron and Copper by Flame Atomic Absorption after Their Preconcentration Using Sodium Dodecyl Sulfate (SDS) Coated Alumina Nanoparticles Modified with 3-Mercapto-D-Valin from Environmental Samples

A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Copper on SDS-coated alumina nanoparticles, which is also modified with 3-mercapto-D-valine. The retained analyte ions on modified solid phase were eluted using 5 mL of 4 mol·L﹣1 HNO3. The analyte determination was carried out by flame atomic absorption spectrometry. The influences of some metal ion and anions on the recoveries of understudy analyte ion were investigated. The influences of the analytical parameters including pH, ligand and SDS amount, eluting solution (type and concentrations) and sample volume on metal ions recoveries were investigated. The extraction efficiency was > 98% with relative standard deviation lower than 3% the method has been successfully applied for the extraction and determination of these ions content in some real samples. Prepared adsorbent was characterized by SEM and FT-IR measurements.

Synthesis and anti-HBV activity of S-substituted 7-mercapto-4-methylcoumarin analogs

Twelve S-substituted 7-mercapto-4-methylcoumarin analogs were synthesized and evaluated for the inhibition to HBV in HepG2 2.2.1.5 cell. Among them, ten compounds exhibited potent inhibition to HBsAg and/or HBeAg with the IC50 values of sub μmol/L level. The ICso of anti-HBsAg activities of 5c and 5j reached 0.01 μmol/L respectively which were 16 fold more potent than that of 3TC. Compounds 3, 5e, 5g, 5h and 5i showed admirable inhibitory activity to both HBsAg and HBeAg. The bioassay results indicated the S-substituted 7-mercapto-4-methylcoumarin analogs merit attention as novel anti-HBV agents.

Synthesis of a New β-Mercaptoalcohol

In this letter, (R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol was synthesized from L-valine and two synthetic routes have been tried.

Chelation in Metal Intoxication XLIV: Efficacy of α-Mercapto β-(5-Substituted, 2-Furyl) Acrylic Acids in Mobilizing Intracellularly Bound Cadmium in Rat

The efficacy of α mercapto β (2_furyl) acrylic acid (MFA), α mercapto β (5_sodiumsulfonate, 2_furyl) acrylic acid (MSFA) and α mercapto β (5_acetoxymethyl, 2_furyl) acrylic acid (MAFA) to mobilize intracellularly bound cadmium in liver and kidney was investigated in rats pre_exposed to cadmium. MFA was effective in reducing cadmium levels of hepatic and renal supernatant cytosolic fraction (SCF) while MSFA and MAFA were effective in lowering cadmium levels of renal SCF and hepatic SCF respectively. All the chelating agents also enhanced the excretion of cadmium more in feces than in urine. However, substitution on the furan ring lowered cadmium mobilizing efficacy of the parent compound, MFA. The treatment with MFA did not affect the status of endogenous zinc and copper while the treatment with MSFA and MAFA enhanced their excretion. MSFA increased hepatic and renal zinc and renal copper while MAFA increased their copper levels.

Synthesis and Crystal Structure of a Novel Mercapto-organotin Complex: [Et_3NH] [Ph_2SnCl(μ~2-SCH_2COO^-)]

A novel complex [Et3NH] [Ph2SnCl(μ2- SCH2COO-)] has been unexpectedly obtained by the reaction of Ph3SnCl and HSCH2COOH in 2:1 molar ratio in the presence of organic base Et3N. Possible dephenylation mechanism was illustrated. The X-ray diffraction study has shown that the title complex consists of cation moiety [Et3NH] and anion moiety [Ph2SnCl(μ2 - SCH2COO)] with tin(IV) in a trigonal bipyramidal coordination geometry.

A facile synthesis of terminal arylacetylenes via Sonogashira coupling reactions catalyzed by MCM-41-supported mercapto palladium(0) complex

许多终端 arylacetylenes 方便地被综合了在对经由 Sonogashira 联合芳基碘化物与的高收益好(trimethylsilyl ) 乙炔由 MCM-41-supported mercapto 钯(0 ) 催化复杂，在温和条件下面由 desilylation 列在后面。没有任何减少，这聚合的钯催化剂能在活动多次被再使用。

5-取代-4-氨基-3-巯基-1,2,4-三唑衍生物的应用进展

5-取代-4-氨基-3-巯基-1,2,4-三唑是一类重要的五元杂环化合物,由于分子中含有巯基和伯胺基两个活性基团,既可以单个基团参与反应生成N-或S-取代产物,又可以同时发生反应生成稠杂环化合物。由其衍生而来的化合物具有广泛的生物活性,在抗菌、抗肿瘤、抗结核、抗炎镇痛、酶抑制剂、荧光探针等方面都表现出优异的性能。综述了近年来5-取代-4-氨基-3-巯基-1,2,4-三唑衍生物在医学、农业及材料领域的应用,为今后进一步研究、开发此类化合物提供参考。

6-巯基-5-三唑并[4,3-b]-s-四嗪(MTT)的密度泛函理论研究

采用密度泛函理论(Density functional theory,DFT),在B3LYP/6-31g(d)(C,H,N,S),Ag原子采用LanL2d赝势基组水平上对甲醛(HCHO)与4-氨基-5肼基-3-巯基-1,2,4-三唑(4-amino-5-hydrazino-3-mercapto-1,2,4-triazole,AHMT)衍生化反应生的成产物6-巯基-5-三唑并[4,3-b]-s-四嗪(6-mercapto-5-triazolo[4,3-b]-s-tetrazine,MTT)及其银配合物进行结构优化,优化结果表明MTT的结构是一个近平面结构.通过对频率计算,获得MTT分子及其银配合物的拉曼光谱,对400-1800 cm^(-1)波段内的拉曼光谱特征峰进行了指认.同时讨论了MTT分子的表面静电势,分析可能发生化学反应的位点.并采用含时密度泛函理论(Time Dependent density functional theory,TDDFT)对MTT分子与Ag3配合物的激发态进行了计算分析,并使用电荷转移光谱对Ag配合物与MTT之间电荷转移关系进行了研究.该研究对MTT分子的光谱测定和电子性质提供了理论基础.

赤铁矿与巯基坡缕石复配对砷镉复合污染土壤修复效应研究

为探讨巯基坡缕石(MPAL)和赤铁矿(Fe2O3)对土壤重金属污染钝化阻控效应,以江西某农田Cd-As复合污染水稻土为供试土壤,采用盆栽试验研究了巯基坡缕石、赤铁矿单一以及复配处理下土壤pH值、Cd-As有效态与形态分布及水稻生物量和Cd、As、Fe含量。结果表明:施加不同材料后水稻籽粒生物量较对照显著增加了2.37~2.45倍,土壤中DTPA-Cd含量显著降低16.94%~22.57%(P<0.05)。土壤连续浸提形态分析显示,MPAL和Fe2O3复配处理提高了土壤中无定形态铁氧化物结合态Cd、As含量。MPAL和Fe_(2)O_(3)复配处理下水稻根系Cd和As含量降幅分别达7.14%、25.13%,不同处理下稻米Cd含量降幅为40.00%~60.00%,但籽粒As含量处理间差异不显著。研究表明,巯基坡缕石和赤铁矿复配材料可以有效降低土壤中Cd和As含量,减少水稻对Cd和As的吸收,具备Cd-As复合污染农田修复和安全利用的潜在应用价值。

离子液体催化合成巯基丙酸甲酯的性能分析及表征

采用一步法合成吡咯烷酮-硫酸离子液体催化剂,利用红外光谱仪、液相色谱仪、热重分析仪、核磁共振氢谱等对其进行表征。研究了该离子液体对甲醇与巯基丙酸酯化反应的催化性能,并与传统浓硫酸催化剂的催化性能进行比较。结果表明,合成物质为[Hnhp]HSO_(4)离子液体且纯度为96%;与传统浓硫酸催化剂相比,以[Hnhp]HSO_(4)离子液体为催化剂时反应时间短,产品的收率高于浓硫酸催化剂产品收率约5%;[Hnhp]HSO_(4)离子液体重复10次试验后,催化剂性能没有降低,且产品收率在85%左右。

Control of the agglomeration of crystals in the reactive crystallization of 5-（difluoromethoxy）-2-mercapto-lH- benzimidazole

5-（Difluoromethoxy）-2-mercapto- 1H-benzimi- dazole （DMB） was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope （PVM）. We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.

Catalytic asymmetric borane reduction of prochiral ketones using chiral camphor-derived mercapto-alcohols

Easily available D-(+)-camphor-derived chiral mercapto-alcohols 2 and 3 were employed for catalytic asymmetric borane reduction of aromatic ketones. Moderate enantioselectivities with e.e. 20.2–72.1% were obtained with 10 mol% catalyst. Opposite asymmetric induction was achieved' when mercapto-alcohols 2 and 3 were used.

Catalyst-free Multicomponent Synthesis of β-Mercapto Diketones in Water

一条简单、有效、 eco 友好的线路在水里经由醛， acetylacetone 和 thiol 的 multicomponent 反应为 -mercapto diketones 的合成被开发了。这方法论负担得起很多 -mercapto diketone 衍生物在对好收益中等。

巯基改性褐煤的制备及其对Fe^(2+)、Mn^(2+)的吸附特性研究

针对酸性矿山废水中Fe^(2+)、Mn^(2+)含量高,褐煤吸附能力有限等问题,以褐煤为基料,选取硅烷偶联剂3-巯基丙基三甲氧基硅烷(MPTMS)作为改性试剂对褐煤进行改性处理。通过单因素试验单独考察各影响因子变化对响应值的影响,应用响应面法(RSM)进一步确定了各影响因子的交互作用,利用EDS能谱、扫描电镜(SEM)、傅立叶变换红外吸收光谱仪(FTIR)等手段对复合材料进行了表征。结果表明,单因素试验确定巯基改性褐煤较优制备条件为褐煤粒径0.18 mm(80目)、褐煤与甲醇质量比为1∶3、反应温度40℃。利用Design-Expert软件进行优化配比,综合考虑去除率与成本后,提出本试验巯基改性褐煤的最佳配比为:褐煤粒径0.18 mm(80目),褐煤与甲醇质量比为1∶4,反应温度为40℃,其Fe^(2+)、Mn^(2+)去除率分别为84.2%、88.9%,饱和吸附容量分别为6.715、2.295 mg/g,较原褐煤Mn^(2+)去除率提升44.9%,Fe^(2+)吸附容量提高27.42%,Mn^(2+)吸附容量提高29.01%。改性褐煤吸附Fe^(2+)、Mn^(2+)的等温吸附线均符合Langmuir模型,吸附符合单分子层吸附过程。由表征结果可知,褐煤经巯基改性后表面结构遭到破坏,出现大量孔道结构,极大增加了比表面积;同时,MPYMS分子结构中含有硅氧基和巯基,硅氧基易与含有巯基的载体物质发生水解反应,形成—C—Si—O—键,从而将巯基接枝到载体物质表面,且重金属离子与吸附剂表面集团的结合可能会促进其骨架变形或断裂,生成碎片分子,暴露更多的羟基,增加吸附点位,提高褐煤吸附能力。

汉麻球蛋白酶解产物中巯基肽的含量及分布研究

采用DTT还原结合Sephadex LH-20葡聚糖凝胶层析的方法分离测定了汉麻球蛋白3种酶解产物中巯基肽的含量,测定结果显示:碱性蛋白酶>胃蛋白酶>木瓜蛋白酶。采用LC-MS-MS检测并鉴定出3种蛋白酶酶解物中巯基肽的分布和序列,结果显示:碱性蛋白酶酶解物中巯基肽数量为41个,木瓜蛋白酶和胃蛋白酶酶解物中都是31个,来源均是Edestin2、Edestin3、清蛋白和非特征蛋白。3种酶酶解获得的麻仁球蛋白(Edestin)巯基肽大部分为亲水性的,分子质量主要分布于1000~2000 u,其中10个是3种酶解产物共有的,碱性蛋白酶和胃蛋白酶酶解物中有4个相同的来源于Edestin3的麻仁球蛋白巯基肽。胃蛋白酶酶解得到1个独有的源于Edestin2的麻仁球蛋白巯基肽。碱性蛋白酶酶解得到了4个独有的源于Edestin3的麻仁球蛋白巯基肽。3种蛋白酶由于作用位点和效力不同得到的麻仁球蛋白巯基肽数量和分布均有不同,但是碱性蛋白酶酶解汉麻球蛋白可以获得更多的麻仁球蛋白巯基肽,推测碱性蛋白酶可以更好地打开汉麻球蛋白中的二级及以上结构,使二硫键更多地暴露出来。

巯基羧酸类有机物对无氰亚硫酸盐体系电镀金的影响

通过直流电沉积、紫外-可见(UV-Vis)分光光度法、扫描电镜(SEM)、X射线衍射(XRD)等手段研究了3-巯基丙酸、巯基丁二酸、1-巯甲基环丙基乙酸和2-氨基-3-巯基丙酸4种巯基羧酸类有机物对无氰亚硫酸盐电镀金体系镀液稳定性和镀层性能的影响。结果表明:在pH 6.0~8.0范围内适量加入巯基丁二酸可以显著提高镀液的稳定性,这可能是因为巯基丁二酸与Au~+形成了稳定的配合物,镀液常温保存6个月仍清澈透明。在Au^(+)3 g/L、巯基丁二酸6.750 g/L、润湿剂3.4 mL/L、pH 6.0(柠檬酸-磷酸氢二钠缓冲体系)、温度40℃、电流密度0.5 A/dm^(2)的条件下电镀10 min,能够得到厚度为1.5~2.0μm的镀金层,其表面均匀致密,结合力、耐蚀性及可焊性良好。

巯基-苯基聚倍半硅氧烷对甲基乙烯基硅橡胶阻尼性能的影响

为改善甲基乙烯基硅橡胶的阻尼性能,采用共混的方式引入阻尼剂巯基-苯基聚倍半硅氧烷,研究了阻尼剂的用量对甲基乙烯基硅橡胶力学性能和阻尼性能的影响。结果表明,当巯基-苯基聚倍半硅氧烷添加量为4phr时效果最佳,硅橡胶能兼顾力学性能与阻尼性能,所得改性硅橡胶的拉伸强度为5.1MPa、撕裂强度为19.7N/mm、损耗角为17.2°。

新型酸铜电镀加速剂MA的应用研究

酸性电镀铜是重要的电子互连制造技术之一。为解决其工业生产过程中,聚二硫二丙烷磺酸钠(SPS)和3-巯基-1-丙烷磺酸钠(MPS)稳定性欠佳,导致镀液老化,使添加剂监控失效、镀液均镀能力下降和镀层结瘤等问题,通过电化学实验、定量分析实验和电镀实验,研究了巯基丙烷磺酸络二铜(MA)作为电子互连中酸铜电镀加速剂的特性。结果表明,MA能够直接替代原配方中的SPS和MPS,作为酸铜加速剂使用,且工作浓度更低,具有更宽的CVS分析线性区间,能够提供更准确的定量分析结果,在微通孔保型电镀中表现出良好的均镀能力,并能实现微盲孔的超级填充,不改变铜镀层的金相织构等,展现出广阔的应用前景。