Derivatives of the closo-dodecaborate anion and their application in medicine

The paper presents a comparative analysis of the possibilities and characteristic features of the application of various polyhedral boron compounds, viz., the closo-decaborate anion [B₁₀H₁₀]^2–, the closo-dodecaborate anion [B₁₂H₁₂]^2–, the carba-closo-dodecaborate anion [CB₁₁H₁₂]^–, carboranes C₂B₁₀H₁₂, and the bis(dicarbollide) complexes [M(C₂B₉H₁₁)₂]^– (M = Fe, Co, or Ni), in boron neutron capture therapy (BNCT) for cancer. The requirements on compounds used in BNCT are formulated and the advantages of the application of the closo-dodecaborate anion are considered. The data on the synthesis of various derivatives of the closo-dodecaborate anion, which either already found use in BNCT or are most promising in this field, are summarized. The possibilities of the application of agents derived from the closo-dodecaborate anion in medical diagnostics are discussed.     

内分子DIELS-ALDER反应合成DRIMANE类倍半萜化合物DRIMENIN, POLYGODIAL及CINNAMOLIDE的全合成

近年来有不少报道从事于生理活性Drimane类倍半萜的合成,较多采用了分子间Diels-Alder反应来建立Drimane的骨架。本文首次采用内分子Diels-Alder反应作为关键反应合成了Drimane类化合物。同时还在引入了手性诱导基团后,首次完成了从无手性的原料化合物β-紫罗兰酮至光学活性(-)-drimenin1的不对称合成。     

Superstability estimates for anharmonic systems

We consider an anharmonic crystal described by variablesS _x ,x ^d ,S _x , with one-body interaction ¦S _x ¦ and nearest neighbor (n.n.) two body interaction ¦S _x –S _y ¦. We prove that, for ^d bounded, , where is the correlation function for the free boundary condition Gibbs state in ,>0 and are suitable constants independent of and . This generalizes previous results obtained in the case.Research partially supported by Consiglio Nazionale delle Ricerche.     

Simultaneous screening and determination eight phthalates in plastic products for food use by sonication-assisted extraction/GC-MS methods

Studies on determination of eight kinds of phthalates, e.g. di-ethyl phthalate (DEP), di-propyl phthalate (DPP), di-isobutyl phthalate (DIBP), di-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-cyclohexyl phthalate (DCHP), di-(2-ethylhexyl) phthalate (DEHP), di-octyl phthalate (DOP), in 25 kinds of plastic products for food use, including packaging bags, packaging film, containers, boxes for microwave oven use, sucking tubes, spoons, cups, plates, etc. by gas chromatography in combination with mass spectrometry detector (GC-MS) in electronic ionisation mode (EI) with selected-ion monitoring (SIM) acquisition method (GC-MS (EI-SIM)) have been carried out. Methods have been developed for both qualitative and quantitative analysis of phthalates. Extraction, clean-up and analysis procedure have been optimized. Determination of samples were performed after frozen in liquid nitrogen and sonication-assisted extraction with hexane, clean-up with LC-C18 SPE and analyzed by GC-MS methods. The base peak (m/z = 149) of all the phthalates was selected for the screening studies. The characteristic ions, 121, 177, 222 for DEP; 191, 209 for DPP; 57, 223 for DIBP; 104 for DBP; 91, 132, 206 for BBP; 55, 167 for DCHP; 113, 167, 279 for DEHP; 279 for DOP were chosen for quantitative studies. These techniques are possible to detect phthalates at the level of 10.0 μg/kg. Overall recoveries were 82-106% with R.S.D. values at 3.8-10.2%. Only one of the 25 examined samples was free from phthalates. The rest 24 samples were found to contain at least three or more of these phthalates. The predominant phthalate detected in the studied samples was DEHP.     

Continuous determination of carbon dioxide evolved during thermal decomposition reactions

A simple device suitable for continuous monitoring of carbon dioxide evolved during thermal decomposition reactions is described. Carbon dioxide is transported by a carrier gas through the device connected to thermoanalytical equipment and absorbed by soda lime reagent. The reaction heat released is linearly proportional to the amount of carbon dioxide absorbed.     

Magnetic microcapsules for targeted delivery of anticancer drugs

To achieve targeted distribution of anticancer drugs with sustained activity, ferromagnetic ethylcellulose microcapsules containing an anticancer drug, mitomycin C (FM-MMC-mc), were prepared by a method based on phase separation principles. Two prototypes of FM-MMC-mc were made: one with the drug as the core and zinc ferrite on its capsular surface (outer type); the other with both the drug and zinc ferrite as the core (inner type). Both preparations provided a sustained-release property and a sensitive response to conventional magnetic force, although certain differences in the release rate of drug, magnetic responsiveness, and particle size were found between the two dosage forms. Animal studies showed that the magnetic microcapsules could be magnetically controlled in the artery and urinary bladder. VX2 tumors in the rabbit hind limb and urinary bladder were successfully treated with magnetic control of FM-MMC-mc. Pharmacokinetic study revealed that the targeting of the microcapsules markedly enhanced the drug absorption into the surrounding tissues for a prolonged period of time. The results indicate the feasibility and effectiveness of the magnetic microcapsules as a targeted drug delivery system.     

Ba2Cu3O5+δ as an intermediate phase during the synthesis of YBa2Cu4O8

We propose a reaction model for the synthesis of YBa₂Cu₄O₈ under normal pressure conditions, which contains 4 partial reaction steps. In a first step bariumnitrate and copperoxide react to Ba₂Cu₃O_5+δ. This substance will be formed for each mixtures Ba:Cu=2∶3...3∶2. The following two partial reaction steps are connected to Ba₂Cu₃O_5+δ, which reacts with Y₂O₃ and CuO to YBa₂Cu₄O₈ or decomposes to BaCuO₂ and CuO. In a last step parts of BaCuO₂ reacts with Y₂O₃ and CuO to YBa₂Cu₄O₈.     

核磁共振法研究CH2=CHSi（OET）3的水化反应

高强水泥的生产近年来巳成为许多国家发展水泥生产的一个主要方向。在水泥中加入有机单体可以改善混凝土的质量,如加重量比为3％的有机硅烷偶联剂乙烯基三乙氧基硅烷CH_2=CHSi(OEt)_3(简称VTES)于水泥中,即可在较大程度上增加水泥石的强度。     

The absorption spectra of the phenoxyl radical in solid argon

Vacuum ultraviolet photolysis of phenol, phenol-d₆ and anisole during condensation with excess argon at 20 K has produced and trapped the phenoxyl radical as evidenced by structured absorptions at 397.2 and 628.1 nm. A broad photosensitive 416 ± 2 nm band is tentatively assigned to the phenol cation.     

Analysis of polynuclear aromatic hydrocarbons by glass capillary gas chromatography using simultaneous flame ionization and electron capture detection

The possibility of simultaneous application of an electron capture (ECD) and a flame ionization detector (FID) connected to a glass capillary column for analyzing polynuclear aromatic hydrocarbons (PNA) has been investigated. The ECD/FID ratio is determined for 46 PNA compounds. The ratios vary from 0.02 to 117 with relative standard deviations better than 20 percent determined from 10 replicate analyses. The results suggest that the method may be used for obtaining additional evidence in identifying PNA in environmental samples. Impurities and transformation products in the standard were identified by computerized glass capillary gas chromatography/mass spectrometry. Quinones and diones are responsible for the high EC-response determined in some trace components in the standard. An application of the method is shown for PNA from particulates in urban atmospheres.