Synthesis of 1-hydroxy and 1-acyloxypyrrolidin-2-ones

A series of 1-hydroxypyrrolidin-2-ones (v) has been prepared by reduction of gamma-nitrocarboxylic acid esters with Zn dust in the presence of ammonium chloride. Acylation of compounds (v) gave the corresponding 1-acyloxypyrrolidin-2-ones (VI). None of the synthesized compounds showed any significant antiflammatory activity.     

Synthesis and antimyoctic properties of 1-(2-alkyl-2-phenylethyl)-1H-imidazoles

The synthesis of 1-(2-alkyl-2-phenylethyl)-1H-imidazoles was accomplished starting from the corresponding phenylacetonitriles. Via alkylation, esterification, and sodium borohydride reduction-in the presence of lithium iodide-beta-phenylalconols were obtained. Mesylation of these alcohols and refluxing with imidazole in dimethylformamide furnished title compounds, which were active in vitro against dermatophytes, yeasts, other fungi, and gram-positive bacteria and in vivo as well as in vitro against Candida albicans.     

Synthesis of AgGa1-xInxSe2 Polycrystalline Materials

AgGa1-xInxSe2 polycrystals were synthesized by the method of mechanical oscillation and temperature oscillation. X-ray diffraction spectra of polycrystal powder are conformable with the JCPDS cards. Lattice constants a and c calculated from the XRD were found to obey Vegard's law. The melting point of AgGa0.8In0.2Se2 obtained by means of differential scanning calorimetry (DSC) is 796.53 ℃. The DSC curve also show that there are no other transformation points below the melting point. The results indicate that polycrystalline materials synthesized by the method mentioned above are high-quality and can be used to grow single crystals by the vertical Bridgman technology.     

Synthesis of 1- and 2-substituted indazoles as anthelmintic agents

Selective synthesis of 1- and 2-acyl-, alkoxycarbonyl-, and carbamoylindazoles are described. Spectroscopic data which were the basis for structural assignments are presented. These compounds, particularly methyl 2H-indazole-2-carboxylate and N-heptyl-N-methyl-2H-indazole-2-carboxamide, lack the spectrum of anthelmintic activity of the benzimidazole and benzotriazole anthelmintics to which they are structurally related.     

LiMnxNixCo1-2xO2的自蔓延燃烧合成及电化学性能研究

采用自蔓延燃烧法合成LiMn(x)Ni(x)Co(1-2x)O2(x=0.25,0.33,0.4.0.45)系列锂离子电池正极材料,通过X射线衍射(XRD)、X射线光电子能谱(XPS)分析研究钴含量的变化对材料结构的影响;利用场发射电子显微镜(FESEM)对材料的形貌进行了表征.由XPS图谱分析,在LiMn(x)Ni(x)Co(1-2x)O2(x=0.25.0.33,0.40,0.45)中.当x为0.4时合成材料中的Mn(3+)和Ni(3+)相对含量较少.在2.5～4.5 V电压范围和0.5C充放电条件下,LiMn(x)Ni(x)Co(1-2x)O2(x=0.25,0.33,0.40.0.45)的初始放电比容量分别为174,177,180和155 mAh·g(-1),循环40次后的容量保持率分别为87.7%,88.0%,90.9%和87.7%,LiMn(0.4)Ni(0.4)Co(0.2)O2的初始放电比容量最高且循环性能最好.在LiMn(x)Ni(x)Co(1-2x)O2(x=0.25,0.33,0.40,0.45)中,随着钴含量的增加,其倍率性能越好.     

Synthesis conditions for obtaining fine powders of pure and alloyed titanium aluminide without milling

We have studied processes not involving milling for obtaining fine powders of either pure titanium aluminide or titanium aluminide alloyed with chromium and manganese. We consider the effect of heat treatment, pressing pressure, and also the degree of dilution of the starting mixture with titanium aluminide. We show that manganese and chromium form solid solutions based on AlTi that cause an elevation in microhardness by 50% and 80% respectively. We have investigated treatment of titanium aluminide powder particles with an Al₂O₃ coating.     

Synthesis and thermodynamics of oligonucleotides containing chirally pure R(P) methylphosphonate linkages

Methylphosphonate (MP) oligodeoxynucleotides (MPOs) are metabolically stable analogs of conventional DNA containing a methyl group in place of one of the non-bonding phosphoryl oxygens. All 16 possible chiral R(P) MP dinucleotides were synthesized and derivatized for automated oligonucleotide synthesis. These dimer synthons can be used to prepare (i) all-MP linked oligonucleotides having defined R(P) chirality at every other position (R(P) chirally enriched MPOs) or (ii) alternating R(P) MP/phosphodiester backbone oligonucleotides, depending on the composition of the 3'-coupling group. Chirally pure dimer synthons were also prepared with 2'-O-methyl sugar modifications. Oligonucleotides prepared with these R(P) chiral methylphosphonate linkage synthons bind RNA with significantly higher affinity than racemic MPOs.     

Infrared discrimination of enantiomerically enriched and racemic samples of methamphetamine salts

A method has been developed for the synthesis of [18F]fluoroetanidazole, a potential tracer for imaging hypoxia with positron emission tomography. The compound is prepared by an active ester coupling reaction between the 2,3,5,6-tetrafluorophenyl ester of 2-nitroimidazole acetic acid and [18F]fluoroethylamine. [18F]Fluoroethylamine is prepared from N-[2-(toluene-4-sulfonyloxy)-ethyl]-phthalimide and [18F]fluoride and purified by distillation. The overall reaction takes about 90 min and gives a yield, uncorrected, of about 25%. Purification on a reversed-phase column is straightforward.     

Synthesis of 1-(beta-D-glycopyranosyl)-3-deazapyrimidines from 2-hydroxy and 2-mercaptopyridines

The synthesis of new 4- and 5-substituted-3-cyanopyridine nucleosides has been performed by reacting the silylated pyridines and penta-omicron-acetyl-alpha -D-glycopyranose in dichloroethane in the presence of SnCl4. The free nucleosides were tested for their potential activity against HIV and different types of tumor.     

Synthesis and biological properties of 5-o-carboranyl-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil

A novel 5-o-carboranyl-containing nucleoside, 5-o-carboranyl-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil (6, CFAU), was synthesized as a potential intracellular neutron capture agent. This compound was prepared in five steps starting from 5-iodo-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)uracil (1). The desired carboranyl derivative was obtained by addition of decaborane [as the bis(propionitrile) adduct] to the protected acetylenic nucleoside precursor followed by debenzoylation. The synthesis of CFAU was also performed by glycosylation of the suitably protected 5-o-carboranyluracil with the appropriate 2-fluoroarabinosyl derivative. This compound was evaluated for its cytotoxicity in human lymphocytes, monkey cells, and rat and human gliomas cells, as well as for antiviral activity against human immunodeficiency virus and herpes simplex virus type 1. Its biological activity was compared to 5-o-carboranyl-1-(2-deoxyribofuranosyl)uracil in these cell culture systems, human bone marrow cells, and mice. The results obtained to date suggest that CFAU has suitable characteristics as a sensitizer for boron neutron capture therapy.     

Antibacterials and antimycotics: Part 1: Synthesis and activity of 2-pyrazoline derivatives

A series of 3-styryl-1,5-diphenyl and 5-styryl-1,3-diphenyl 2-pyrazolines of different substitutions has been synthesized by condensation of substituted alpha,beta-unsaturated ketones with phenylhydrazine hydrochloride in presence of catalytic amount of concentrated HCl. Compounds in the 3-styryl series had OMe, NMe2, NO2, OH and isopropyl substituents and those in the 5-styryl series had OMe, NMe2 and NOs. The 3-styryl-1,5-diphenyl compounds showed little variation in antibacterial activity towards gram-positive and gram-negative bacteria in terms of geometric mean minimum inhibitory concentrations (MIC). The 4',4"-NMe2, 4',4"-NO2 and 4',4"-OMe compounds were found to possess the highest activity in the series. The 5-styryl-1,3-diphenyl series showed lower activities than the 3-styryl series. The in vitro antimycotic activity of the 4',4"-OH and 2',2"-OH substituted compounds showed good activity than the other molecules in the two series.     

Synthesis and Characterization of Li1＋2x＋3y AlxScyZny Ti2-x-2ySixP3-xO12

Recentyearssomenaturalaluminosilicates ,suchaspyrophylliteandkaolinite ,havebeenusedasastartingmaterialstopreparemineralfastionconduc tors .Meanwhile ,somerareearthelementshavebeenintroducedintomineralfastionconductorsystemtoformsocalledrareearthmineralfastionconductors .Intheareaoffastionconductors ,moreandmoreat tentionhasbeenpaidtolithiumfastionconductorsduetotheirpotentialapplicationinhighenergydensi tybatteryandotherelectrochemicaldevices .Severalcomplexesareknowntoshowhighlithiumioncondu…     

Synthesis and biological activities of 2 beta-chloro-, 2 beta-fluoro-, and 2 beta-methoxy-1 alpha,25-dihydroxyvitamin D3

Using 1 alpha,2 alpha-oxido-cholesta-5,7-diene-3 beta,25-diol (2) as a starting material, the provitamins of calcitriol with an additional 2 beta-chloro-, 2 beta-fluoro-, and 2 beta-methoxy-substituent (3,4,5) are obtained by transdiaxial opening of the oxirane ring with nucleophiles. An efficient irradiation process is described and used for the synthesis of the 2 beta-substituted calcitriols NS2 (2 beta-Cl), NS6 (2 beta-F), and NS7 (2 beta-OCH3). The affinity of these three vitamin D3 derivatives to the vitamin D receptor (VDR) and was determined. These three A-ring derivatives of 1,25(OH)2D3 were further tested for their proliferation-inhibitory and anti-adipogenic activity and gene regulatoric activity in the vitamin D3-sensitive, murine, mesenchymal cell line C3H10T1/2. The VDR-affinity of the 2 beta-chloro derivative, NS2 (2 beta-Cl), was identical to 1,25(OH)2D3 and its vitamin D binding protein (DBP)-affinity was in the range of 1,25(OH)2D3. NS2 inhibited the proliferation of C3H10T1/2(BMP-4)-cells in the presence of fetal calf serum (FCS) 9 times, and, in the absence of FCS, 111 times lower, as compared with 1,25(OH)2D3. The ID50 dose of adipogenesis-inhibition of NS2 was 13 times higher than the ID50 dose of 1,25(OH)2D3. NS6 (2 beta-F) displayed a slightly higher affinity than 1,25(OH)2D3 to the VDR and DBP-affinity. The proliferation-inhibitory activity in the presence of FCS was 90 times higher, as compared with 1,25(OH)2D3. In the FCS-free proliferation assay NS6 displayed an inhibitory activity in the range of 1,25(OH)2D3. NS6 showed an 5 times higher potency to inhibit (pre)adipocyte-differentiation in C3H10T1/2(BMP-4)-cells than 1,25(OH)2D3. NS7 (2 beta-OCH3) showed the lowest VDR-affinity and the highest DBP-affinity of the tested substances, as compared with 1,25(OH)2D3 (11 times lower and 35 times higher respectively). Its proliferation-inhibitory activity in the FCS-free medium was 9 times and in the FCS-containing assay 67 times lower in comparison with 1,25(OH)2D3. A 1250 times higher NS7-dose was needed to reach the anti-adipogenic potency of 1,25(OH)2D3. All tested substances displayed a similar ability to activate a vitamin D responsive element-regulated reporter gene compared to 1,25(OH)2D3 (NS2 and NS6: 1.3 times higher activity; NS7: 1,4 times lower activity).     

Synthesis and biological investigations of 1-(tetrahydropyran-2'-yl)- and 1-(tetrahydrofuran-2'-yl)benzimidazoles and 1/2-(tetrahydropyran-2'-yl)- and 1/2-(tetrahydrofuran-2'-yl)benzotriazoles

Sets of benzimidazole and benzotriazole derivatives bearing on position 1 or 2 a tetrahydrofuranyl or tetrahydropyranyl moieties were prepared through the addition of the suitable benzazoles on 2,3-dihydrofuran and 3,4-dihydro-2H-pyran. The reactions were carried on either without solvent or in carbon tetrachloride solution. In the last case some peculiar chlorinated side products were isolated and characterized. Twenty compounds were screened for in vitro antitumoral and anti-HIV-1 activities and found poorly active or completely inactive. On the other hand several compounds exhibited good tracheal relaxant activity in vitro; compound 8, 11, 16, 24 and 26 resulted more active than theophylline in this test, while compound 11 was comparable to amrinone till the concentration of 3 micrograms/ml. Finally, compound 5 resulted endowed with a strong diuretic and saluretic activity at the dose of 3 mg/Kg, thus representing a new lead for discovering new diuretic agents.     

Synthesis and structure-activity relationships of 3-hydrazono-1H-2-indolinones with antituberculosis activity

OBJECTIVES: To evaluate endometrial responses to three different forms of amenorrhea-inducing HRT in postmenopausal women. MATERIAL AND METHODS: Fifty-one postmenopausal women completing a one-year HRT trial with percutaneous estradiol gel containing 1.5 mg estradiol daily combined with a levonorgestrel-releasing intrauterine device (LNG-IUD) (n=18), or natural progesterone 100 mg daily orally (n= 19) or vaginally (n=15) during 1-25 calendar days of each month. Endometrial thickness and uterine size were measured by transvaginal ultrasound, and endometrial cytology/histology was assessed from specimens taken by needle aspiration before the study and at 12 months. RESULTS: Before medication, the median endometrial thickness was 2.0 mm in the LNG-IUD group, 2.4 mm in the oral P group and 2.5 mm in the vaginal P group. At 12 months of therapy the respective values, 3.0, 2.7 and 2.4 mm, did not differ significantly from the initial values. LNG-IUD induced epithelial atrophy in all women, which was accompanied by stromal decidualization in 12 women. On the contrary, only four women in the oral P group and five women in the vaginal P group had an inactive or atrophic endometrium. The remaining cases were dominated by proliferative features. No hyperplasia was seen in any of the groups. CONCLUSION: LNG-IUD appeared to be an effective method of counteracting the stimulatory effect of estrogen on the endometrium, whereas natural progesterone given orally or vaginally was not sufficiently effective in this function at the doses used. The vaginal and oral administrations of progesterone did not differ from each other in this respect.     

一维纳米LiNi1/3Co1/3Mn1/3O2纤维的合成及性能研究

通过静电纺丝法制备出一维纳米LiNi1/3Co1/3Mn1/3O2纤维,根据扫描电子显微镜(SEM)、X射线衍射(XRD)、充放电实验,循环伏安法和交流阻抗法对纳米纤维的形貌、晶体结构和电化学性能进行研究.结果表明,纳米纤维的直径在150～300 nm之间,且具有典型的α-NaFeO2层状结构;所制备的LiNi1/3Co1/3Mn1/3O2纳米纤维在0.5 C(85 mA/g)的倍率下循环30次容量保持率达到了94.1％;在倍率分别为0.1 C、0.2 C、0.5 C、1.0 C、2.0 C和0.2 C的充放电测试中,其比容量分别达到了157 mAh/g、144 mAh/g、134 mAh/g、125 mAh/g、115 mAh/g和141 mAh/g;在CV和EIS测试中,材料表现出优异的可逆性和循环稳定性.由于具有特殊的一维形貌,LiNi1/3Co1/3Mn1/3O2纳米纤维表现出优异的电化学性能.     

Synthesis of 1,2-diaminopropane derivatives. I. Synthesis of D,L-1-dimethylamino-2-aminopropane]

Forty-eight younger (average CA = 21.71, SD = 3.58) and older (average CA = 69.31, SD = 3.84) males participated in a vocabulary task involving varying degrees of risk under neutral, supportive, and challenging instructions. The results indicated that older adults were more cautious than younger adults. Moreover, they selected tasks at which they would have higher probabilities of success; relative to their younger counterparts, they were less likely to raise their level of aspiration following success. No effect of instructions on cautiousness was found for either age group. The results were interpreted as indicative of the significant age differences in the achievement motivational dispositions of the groups. The findings suggest that older adults choose relatively easy tasks as a means of protecting themselves from engaging in self-evaluation of important ability dimensions.