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Wegen seiner geringen Loslichkeit und der hohen Maximalkonzentration des substanzspezifischen Verdampfers ist Sevofluran fur die Durchfuhrung von Niedrigflusnarkosen besonders geeignet. Ein- und Auswaschphasen konnen kurz gehalten werden, die Differenz zwischen Frischgas- und der Narkosemittelkonzentration im Atemsystem ist vergleichsweise gering und auch bei niedrigem Frischgasflus sind die Zeitkonstanten vergleichsweise kurz. Mit einem standardisierten Dosierkonzept lassen sich reproduzierbare Sevoflurankonzentrationen im Narkosesystem etablieren. Das Monitoring, das zur Gewahrleistung der Patientensicherheit zu fordern ist, gehort zum heute allgemein geforderten sicherheitstechnischen Standard. Wegen der Moglichkeit der Akkumulation von Compound A sollte – bis die wissenschaftliche Diskussion um eine mogliche Nephrotoxizitat dieser Substanz beim Menschen abgeschlossen ist – der Frischgasflow zumindest 1 l/min betragen. Mit der Low Flow-Anasthesie wird ein kontinuierliches Auswaschen von Fremdgasen aus dem Narkosesystem gewahrleistet. Streng mus bei der Anwendung von Sevofluran darauf geachtet werden, das der Atemkalk nicht ausgetrocknet ist. An trockenem Atemkalk wird Sevofluran in einer stark exothermen Reaktion fast vollstandig absorbiert und in nennenswerter Menge chemisch abgebaut, wobei die fluchtigen Abbauprodukte die Atemwege reizen und evtl. toxisch sind. Nur mit der Low Flow-Anasthesie erreicht die Anwendung von Sevofluran eine wirtschaftlich und okologisch vertretbare Effektivitat.

In the presence of carbon dioxide absorbents, sevoflurane is degraded to CF2=C(CF3)OCH2F, an olefin compound A. There remains some concern of the hepatic and renal toxicity that compound A poses when using low-flow anaesthetic techniques. We investigated a device to decrease the concentration of compound A products by decreasing the temperature of exhaled air and soda lime in semi-closed low-flow anaesthesia technique in surgical patients. Ten patients, ASA 1 or 2, were studied. Five received anaesthesia using a cooling circuit, that consisting of an anaesthetic circuit and an intercooler device interposed in the expiratory tube. The intercooler was dipped in an iced water tank. Anaesthesia was given through this circuit from induction to emergence. Another five patients received anaesthesia without cooling. Anaesthesia was maintained with sevoflurane and O2 50%/N2O during four to six hours of operation. A fixed concentration of sevoflurane 2% at a total flow of 1 L·min−1 was administered. Gas samples were taken every hour and compound A was quantitated by gas chromatography. The temperatures of canister, circuit and body were measured every hour. The device effectively lowered the temperatures [24 ± 3.4 to 5 ± 1,3°C] and the concentrations of compound A [27.1 ± 3.8 ppm to 16.3 ± 2.08 ppm,P < 0.05] in the circuit. The body temperatures were not lowered. Compound A concentrations were reduced by cooling the anaesthetic circuit in clinical settings. En presence d’absorbants du gaz carbonique, le sevoflurane se degrade en CF2=C(CF3)OCH2F, un compose olefine A. Ce qui nous fait toujours craindre une certaine toxicite hepatique et renale possible lors de l’emploi de techniques anesthesiques a debit lent. Nous avons fait l’essai d’un dispositif qui diminuerait la concentration du compose A en abaissant la temperature de l’air expire et de la chaux sodee dans un circuit anesthesique semi-ferme a debit lent. Dix patients, ASA I ou II, ont ete etudies. Cinq d’entre eux ont recu une anesthesie avec l’emploi d’un appareil refroidisseur interpose sur le tube d’expiration du circuit d’anesthesie. Le refroidisseur etait plonge dans un reservoir d’eau glacee. L’anesthesie a ete administree par ce circuit depuis l’induction jusqu’au reveil. Les cinq autres patients ont recu une anesthesie sans refroidissement. Lanesthesie a ete maintenue avec du sevoflurane et un melange d’O2 et de N2O a 50 % pendant les quatre a six heures de l’intervention. Une concentration fixe de 2 % de sevoflurane a un debit total de 1 L·min−1 a ete administree. Des echantillons de sang ont ete preleves a chaque heure et le compose A a ete mesure par Chromatographie en phase gazeuse. Les temperatures de la chaux, du circuit et du corps ont ete mesurees a chaque heure. Le dispositif a efficacement reduit les temperatures [de 24 ± 3,4 a 5 ± 1,3°C] et les concentrations du compose A [de 27,1 ± 3,8 ppm a 16,3 ± 2,08 ppm,P < 0,05] dans le circuit. La temperature du corps n’a pas baisse. Les concentrations de compose A ont ete reduites par le refroidissement du circuit anesthesique en pratique clinique.

The reduction of dioxygen to water by cytochrome c oxidase was monitored in the Soret region following photolysis of the fully reduced CO complex. Time-resolved optical absorption difference spectra collected between 373 and 521 nm were measured at delay times from 50 ns to 50 ms and analyzed using singular value decomposition and multiexponential fitting. Five processes were resolved with apparent lifetimes of 0.9 micros, 8 micros, 36 micros, 103 micros, and 1.2 ms. A mechanism is proposed and spectra of intermediates are extracted and compared to model spectra of the postulated intermediates. The model builds on an earlier mechanism that used data only from the visible region (Sucheta et al. (1997) Biochemistry 36, 554-565) and provides a more complete mechanism that fits results from both spectral regions. Intermediate 3, the ferrous-oxy complex (compound A) decays into a 607 nm species, generally referred to as P, which is converted to a 580 nm ferryl form (Fo) on a significantly faster time scale. The equilibrium constant between P and Fo is 1. We propose that the structure of P is a3(4+)=O CuB2+-OH- with an oxidizing equivalent residing on tyrosine 244, located close to the binuclear center. Upon conversion of P to Fo, cytochrome a donates an electron to the tyrosine radical, forming tyrosinate. Subsequently a proton is taken up by tyrosinate, forming F(I) [a3(4+)=O CuB2+-OH- a3+ CuA+]. This is followed by rapid electron transfer from CuA to cytochrome a to produce F(II) [a3(4+)=O CuB2+-OH- a2+ CuA2+].

Olpadronate is a nitrogenated bisphosphonate. Although it shares the therapeutic and pharmacological properties of pamidronate and alendronate, it has a greater dosage amplitude, more predictable effects and a greater digestive tolerability than other bisphosphates. Therefore, it may be more appropriate in the treatment of medical osteopathies, by both oral and parenteral routes of administration. According to various experimental and human models, the pharmacological potency of olpadronate is 5- to 10-times higher than that of pamidronate and close to that of alendronate. The two methyl groups bound to the nitrogen atom give the compound a high water solubility, which is about 8-times higher than that of the two other bisphosphonates. The lack of a terminal amino group in the side-chain of the molecule and the absence of crystallised forms of the compound in the digestive tract (due to its high water solubility) may avoid the potential for inducing oesophageal and gastrointestinal side-effects. These features may explain the high tolerability reported after the administration of doses of olpadronate (by the oral route) up to 5- to 10-times higher than the maximum tolerated dose of alendronate in Paget's bone disease and bone metastases, thus widening the possibilities for its clinical usage. In addition, initial pharmacokinetic studies suggest that olpadronate's oral bioavailability would fit into a confidence range of 2-4%, which contrasts with the erratic absorption shown by other highly potent bisphosphonates. The clinical efficacy demonstrated in preliminary studies in Paget's bone disease (including ultra-short treatments), and also in single-dose iv. therapy of hypercalcaemia of malignancies, renders olpadronate among the most promising bisphosphonate compounds, with potential use in the treatment of a variety of bone-involving diseases, such as osteoporosis, malignancies and rheumatoid arthritis.

An o-bromophenylzinc compound, first prepared in an excellent yield by the reaction of o-bromoiodobenzene with zinc powder in THF, was found to be an efficient synthetic equivalent of o-phenylene 1-anion 2-cation in Pd(0)-catalyzed stepwise cross-coupling reactions, affording unsymmetrically 1,2-disubstituted benzenes with diverse substitution patterns and with a variety of functional groups.

We performed low-flow sevoflurane anaesthesia at a flow rate of 1 litre min-1 in three groups (n = 8 each) using 600 g of fresh soda lime (control group), 600 g of soda lime with 60 ml of water added (water group) or 600 g of soda lime saturated with carbon dioxide, that is partly exhausted soda lime (carbon dioxide group). Degradation products in the system were measured hourly. Inspired and end-tidal carbon dioxide and sevoflurane concentrations, carbon dioxide and temperature of the soda lime were monitored. CF2 = C(CF3)-O-CH2F (compound A) was the only sevoflurane degradation product detected. The mean maximum concentration of compound A was significantly higher in the control group (mean 16.0 (SD 5.0) ppm) than in the water (1.4 (1.0) ppm) or carbon dioxide (4.0 (1.8) ppm) group, and the maximum temperature of the soda lime was significantly lower in the carbon dioxide group (30.7 (3.5) degrees C) than in the control (43.4 (1.8) degrees C) or water (40.8 (1.8) degrees C) group (P < 0.05). The use of partly exhausted soda lime or soda lime with water added reduced compound A concentrations in the system during low-flow sevoflurane anaesthesia.

Sevoflurane (CH2F-O-CH[CF3]2) reacts with carbon dioxide absorbents to produce Compound A (CH2F-O-C[=CF2][CF3]). Because of concern about the potential nephrotoxicity of Compound A, the United States package label (but not that of several other countries) for sevoflurane recommends the use of fresh gas flow rates of 2 L/min or more. We previously demonstrated in humans that a 2-L/min flow rate delivery of 1.25 minimum alveolar anesthetic concentration (MAC) sevoflurane for 8 h can injure glomeruli (i.e., produce albuminuria) and proximal tubules (i.e., produce glucosuria and urinary excretion of alpha-glutathione-S-transferase [alpha-GST]). The present report extends this investigation to fasting volunteers given 4 h (n = 9) or 2 h (n = 7) of 1.25 MAC sevoflurane versus desflurane at 2 L/min via a standard circle absorber anesthetic system (all subjects given both anesthetics). Markers of renal injury (urinary creatinine, albumin, glucose, alpha-GST, and blood urea nitrogen) did not reveal significant injury after anesthesia with desflurane. Sevoflurane degradation with a 2-L/min fresh gas inflow rate produced average inspired concentrations of Compound A of 40 +/- 4 ppm (mean +/- SD, 8-h exposure [data from previous study]), 42 +/- 2 ppm (4 h), and 40 +/- 5 ppm (2 h). Relative to desflurane, sevoflurane given for 4 h caused statistically significant transient injury to glomeruli (slightly increased urinary albumin and serum creatinine) and to proximal tubules (increased urinary alpha-GST). Other measures of injury did not differ significantly between anesthetics. Neither anesthetic given for 2 h at 1.25 MAC produced injury. We conclude that 1.25 MAC sevoflurane plus Compound A produces dose-related glomerular and tubular injury with a threshold between 80 and 168 ppm/h of exposure to Compound A. This threshold for renal injury in normal humans approximates that found previously in normal rats.Human (and rat) kidneys are injured by a reactive compound (Compound A) produced by degradation of the clinical inhaled anesthetic, sevoflurane. Injury increases with increasing duration of exposure to a given concentration of Compound A. The response to Compound A has several implications, as discussed in the article.

A structure determination using high resolution neutron powder data (difference Fourier maps) has shown that the hexagonal compound TbCr 6 Ge 6 (P6/ mmm ) is a partly disordered derivative of the HfFe 6 Ge 6 -type structure where a part of the Tb atoms at 1(a) (0,0,0) and a part of the Ge 3 atoms at 2(e) (0,0,0.347) populate intermediate lattice positions which are shifted by c /2. The observed atomic disorder modifies the R-R inteactions as well as the crystal field, leading to an ordered state and easy axis for the Tb moments different from that found for the (fully ordered) isomorphic TbMn 6 Ge 6 compound. As the CrCr interaction is very weak the ordering is dominated by the R-R interaction. TbCr 6 Ge 6 orders below T c = 10.3 K with a canted ferrimagnetic moment arrangement where the moments of the Tb and Cr sublattices have different orientations making an angle of 25(2) deg. and 143(7) deg. with the c -axis respectively. The ordered moment values of the two sublattices at 1.5 K are 8.74(1) μ B /Tb and 0.48(10) μ B /Cr. The net magnetic moment of the structural model proposed is found to be in satisfactory agreement with results of magnetic measurements reported earlier.

Combined sensitizations to different azo dyes, probably based both on true cross-sensitization and on simultaneous positive reactions, have frequently been described. However, since azo dyes are included in the standard series in a minority of countries, the case studies considered comprise, with few exceptions, a small number of subjects. The aim of our study was to investigate cross-reactions between different azo dyes and para-amino compounds in azo-dye-sensitive subjects, to study the clinical aspects of azo dye dermatitis, to assess the relevance of sensitization to azo dyes, and to relate the pattern of cross-sensitizations to the chemical structure of the different dyes. Out of 6203 consecutively tested patients, 236 were sensitized to at least 1 of 6 azo compounds employed as textile dyes, included in our standard series. 107 subjects reacted to Disperse Orange 3 (DO3), 104 to Disperse Blue 124 (DB124), 76 to p-aminoazobenzene (PAB), 67 to Disperse Red 1 (DR1), 42 to Disperse Yellow 3 (DY3), and 31 to p-dimethylaminoazobenzene (PDAAB). Co-sensitizations to para-phenylenediamine were present in most subjects sensitized to DO3 (66%) and PAAB (75%), in 27% and 36% of DR1 and DY3-sensitive subjects, and only in 16% of subjects sensitized to DB124. Apart from the hands and the face, the neck and the axillae were the most frequently involved skin sites. Whereas the involvement of flexural areas was mainly connected with sensitization to DB124, in patients with hand dermatitis and in those working as hairdressers, sensitization to DO3 and PAAB was more frequent. Moreover, in the former patient group, a history of textile dye allergy was most frequently obtained. Out of 33 patients tested with an additional textile dye series, only 5 subjects reacted to anthraquinone dyes. Cross-sensitizations between azo dyes and para-amino compounds can partially be explained on the basis of structural affinities.

In discussing the Chl b biosynthetic pathway, use will be made of kinetic analysis of precursor-product relationships in vivo. In 1988, equations were derived to investigate possible precursor-product relationships in branched, and interconnected pathways (Rebeiz et al. 1988; Tripathy and Rebeiz 1988). It was shown that for any two compounds A and B, formed from a common precursor P such as ALA, and having a possible direct precursor-product relationship between them, for any number of time intervals t1 to t2, the following equation describes the relationship between the specific radioactivity of compound A, possible radiolabel incorporation from compound A into compound B, and the net synthesis of compound B from compound A (Rebeiz et al. 1988): $$ {\bf Q}{{{\bf B}}_2}={(^{*}}{{{\bf A}}_1}{+^{*}}{{{\bf A}}_2})/2)\cdot {(^{*}}{{{\bf B}}_2}) $$

Article history: Received on: 19/12/2012 Revised on: 09/01/2013 Accepted on: 19/01/2013 Available online: 28/01/2013 From methanol extract of Kalanchoe pinnata (Lam.) Pers. leaves, a flavonol compound has been isolated. Fractionation of the methanol extract with ethyl acetate, followed by ethyl acetate fraction purification using column chromatography method with ethyl acetate : n-hexane as mobile phase gave a yellow crystal compound (A). Further analysis using 1Dand 2D-nuclear magnetic resonance (NMR), confirmed with mass spectrometer (LC-MS), compound A identified as 3’,4’-dimethoxy quercetin.

The synthesis of new fluorinated α,ω-diiodo telomers I(TFE) x (VDF) y (HFP) z I (A) where TFE, VDF and HFP represent tetrafluoro-ethylene, vinylidene fluoride and hexafluoropropene, respectively, was carried out by thermal telomerization of HFP with VDF oligomers, I(TFE) x (VDF) y I, as transfer agents. Compound A was obtained in 55% yield when x = y = 1, whereas almost no reaction occurred when x = 1 and y = 2. Interestingly, HFP reacted with IC 2 F 4 CH 2 CF 2 · selectively and not with ICF 2 CH 2 CF 2 CF 2 · whereas, from IC 4 F 8 CH 2 CF 2 I, HFP could be introduced on both end-groups but produced a higher amount of I(TFE) 2 (VDF)(HFP) I. The reactivity of HFP is compared with that of VDF in reactions with fluorinated α,ω -diiodinated telogens and it is shown that the environment of the terminal C-I bond in the telogen influences the orientation of the reaction.

The present paper addresses the potential use of capillary zone electrophoresis (CZE) as an analytical tool in 99- technetium speciation studies. In order to optimise sampling, storage and analytical procedures, the three marker compounds 99mTcO4-, 99mTc-DTPA and 99mTc-citrate were synthesised and used in test-measurements with CZE. The results underline the superior separation power of the CZE technique, and indicate good CZE performance for the stable 99mTcO4- and 99mTc-DTPA compounds. The data suggest that CZE may be used without problems for various Tc-compounds of intermediate mobilities. The specific data of 99mTc-citrate suggest that with this marker compound a threshold lability is reached for the use of CZE in plant Tc-speciation studies. This result means that CZE cannot be used in analyses of Tc-compounds which are less stable than Tc-citrate. Future CZE work will comprise the synthesis and use of Tc-markers of intermediate mobilities and stabilities; furthermore, effects of marker matrices and the plant matrix on CZE performance will be investigated.

This article reviews the physico-chemical properties and performance characteristics of the two new potent inhaled anesthetics, desflurane and sevoflurane. Both drugs provide a greater degree of control of anesthetic depth and a more rapid immediate recovery from anesthesia than is currently available with other inhaled agents because of their decreased solubility. Desflurane is currently in widespread clinical use in the United States and parts of Europe. Compared with sevoflurane, it has the additional advantage of being extremely resistant to degradation and biotransformation. However, its pungent odor and tendency to irritate the respiratory tract make it unsuitable for inhalational inductions, and it has been linked to CO production in CO2 absorbents. The sympathetic nervous system activation that occurs with desflurane limits its use in patients with cardiac disease. Otherwise, its hemodynamic and physiologic effects are similar to those seen with isoflurane. Studies of the economics of using desflurane are mixed, although it may offer the advantage of shorter postoperative recovery time. Sevoflurane is currently in widespread clinical use in Japan and parts of South America. The FDA Advisory Panel has recently recommended approval of sevoflurane in the United States, and we can expect the drug to be clinically available in the United States in the second quarter of 1995. Compared with desflurane, sevoflurane has the additional advantage of being nonirritating to the airway; inhalational induction of anesthesia with sevoflurane is achieved rapidly and easily. The instability of sevoflurane with CO2 absorbents and its in vivo biotransformation produce potentially toxic byproducts. These byproducts, including Compound A and fluoride, have been extensively studied, and although the possibility for iatrogenic sequelae from sevoflurane exists, the likelihood of long-term toxicity appears quite low. Phase IV studies are indicated to determine the safety of administering sevoflurane (1) to renally impaired patients and (2) to any patient with fresh gas flows less than 2 L/min. Sevoflurane is otherwise very well tolerated and appears to offer the advantage of rapid and smooth induction and emergence from general anesthesia.

The synthesis of calix[4]arenes permuting 1 or 4 C12 acyl chains at the upper rim and 1 or 4 methylene ethyl ester groups at the lower rim is described. The Langmuir compression isotherms of the compounds show that in the case of 1 acyl + 1 ester, there is probably orientation parallel to the air-water interface. For the other systems, orientation is orthogonal to the interface, and for the 4 +4 compound a pseudo collapse with reorientation of the hydrophilic ester groups is observed.

Comparing dose-response curves (DRCs) of a compound A in the absence and presence of a fixed dose of an antagonist B is standard in pharmacology and toxicology. When B qualitatively resembles A in its action, it is often useful to construct theoretical DRCs of additive and independent combinations. Theoretical curves are calculated from experimental values by the program ALLFIT, which uses the four parameter logistic equation. DRCs of theoretical, additive DRCs are obtained by using the respective values for slope and ED50, which were taken from tables presented here compiled on the basis of the slope of the DRC of A alone (0.6-14) and of the effect of B alone (1-75%). These tables are unnecessary for the construction of theoretical curves if A acts by an independent mechanism, giving values for slope and ED50 identical to those of the DRC of A alone. Experimental DRCs of antiviral and other effects (the latter taken from data in the literature) are compared with theoretical curves by an F-test analysis provided by ALLFIT. The method can be used successfully for the construction of theoretical curves for additive and independent DRCs and comparison with experimental curves. This comparison may help clarify the mode of interaction of A with B.

The electronic properties and topological phases of ThXY (X = Pb, Au, Pt, Pd and Y = Sb, Bi, Sn) compounds in the presence of spin–orbit coupling, using density functional theory are investigated. The ThPtSn compound is stable in the ferromagnetic phase and the other ThXY compounds are stable in nonmagnetic phases. Band structures of these compounds in topological phases (insulator or metal) and normal phases within generalized gradient approximation (GGA) and Engel–Vosko generalized gradient approximation (GGA_EV) are compared. The ThPtSn, ThPtBi, ThPtSb, ThPdBi, and ThAuBi compounds have topological phases and the other ThXY compounds have normal phases. Band inversion strengths and topological phases of these compounds at different pressure are studied. It is seen that the band inversion strengths of these compounds are sensitive to pressure and for each compound a second-order polynomial fitted on the band inversion strengths–pressure curves.

Birdsongs are an integral part of many landscapes, in urban and countryside areas. Together they constitute an ecological network of interacting sonic agents that are self-organised into an open complex system of similar cognitive aspects, yet with original acoustic content. This work presents a preliminary study and development of an evolutionary algorithm (EA) used here for the generation of virtual birdsongs that create an artificial sonic landscape; a soundscape of birdsongs. They are reproduced by genetic operators that build sequences of parameters to control instantiations of a computer model that emulates a bird syrinx. Such models are capable of synthesising a wide range of realistic birdsongs that altogether compound a dynamic network of artificial bird calls. This system can also be interactive as external input data can be received in real-time through instant text messages from the micro-blog Twitter. These messages are mapped as new individuals living in the EA system population set. As furt...

Treatment of an aryl-sec-alkyl unsymmetrical thiourea (Tu) with Cu(II)X(2) (X = I, Br) transform the thiourea (Tu) into a thioamidoguanidino (Tag) moiety with concomitant reduction of Cu(II) to Cu(I), which forms a [Cu(2)(I)(μ(2)-X)(2)Tag(2)] (X = I (for A) and X = Br (for B)) complex. Meanwhile, the treatment of same unsymmetrical thiourea (Tu) with Cu(I)X (X = Br) forms a stable cluster with a [Cu(I)(3)(μ(2)-S)(4)Tu(4)X(3)] core (C). Single crystal X-ray diffraction revealed that compounds A and B exhibit 1D chain with a Cu(2)(μ(2)-X)(2) core, whereas compound C is a Cu(I)(3)S(4)Br(3) cluster. Compound A is centrosymmetric due to the trans orientation of two Tag units whereas compound B is ascentric due to the cis orientation of two Tag units. In compound A, the Cu(2)I(2) core is perfectly rhomboidal where the iodine atoms are trans oriented. However in compound B, the Cu(2)Br(2) core is not perfectly rhomboidal (bowl shaped) and the bromine atoms are cis oriented. It is interesting to note that although the Tag moiety in compounds A and B contain two morpholine-O atoms; only one of the morpholine-O atoms (O2) is involved in the generation of three-dimensional network. The Cu(I)(3)S(4)Br(3) cluster in compound C contains one tri- and two tetra-coordinated Cu(I) centers. The Cu(I) cluster in C contains a Cu(2)(μ(2)-S)(2) rhomboidal plane exhibiting a chair and a boat form containing the Cu(I)(3)S(3) unit. In compounds A and B, the two Cu(I) centers are μ(2)-X bridged and have a μ(1)-S linkage, whereas in compound C the linkages are opposite having four μ(2)-S bridges and three μ(1)-Br linkages.

BackgroundAn olefin called compound A (CF2 == C(CF3)OCH2F) results from the action of soda lime or Baralyme on sevoflurane. We have demonstrated that rats exposed to the olefin for 3 h died at or were injured by olefin concentrations lower than those previously reported to produce these effects. The

The nucleophilic attack of alcohols, amines and iodine on the magnesium atoms of [Me2Al(µ-NPri2)2MgMe]4A and [Me2Al(µ-NEt2)2MgMe]2B has been investigated. Compound A undergoes metathesis with amines (Et2NH and Pri2NH) and iodine to give [Me2Al(µ-NPri2)2Mg(µ-NR2)](R = Et 7 or Pri4) and [Me2Al(µ-NPri2)2Mg(µ-I)]25, respectively. Partial degradation of A with MeOH or ethanol gives Me2Al(µ-NPri2)(µ-OMe)Mg(µ-NPri2)(µ-OMe)AlMe21a and [Me2Al(µ-NPri2)(µ-OEt)Mg(µ-NPri2)(µ-OEt)AlMe21b, respectively, whereas partial degradation with ButOH gives Me2Al(µ-OBut)2Mg(µ-OBut)2AlMe22 and [Me2Al(µ-OBut)2Mg(µ-OBut)]23. Compound B undergoes metathesis with ButOH also to give 2 and 3. The intermediate, Me2Al(µ-NR2)2Mg(µ-Me)(µ-OBut)Mg(µ-NR2)2AlMe2I in the reactions of A and B with ButOH is also examined. The molecular structures of compounds 1b, 2, 3 and 5 were determined by X-ray diffraction.

The double-distorted perovskites Ca(Cu${}_{3\ensuremath{-}x}$Mn${}_{x}$)Mn${}_{4}$O${}_{12}$ ($x$ = 1, 1.25, 1.5, and 2) exhibit a paramagnetic-to-ferrimagnetic transition at a temperature decreasing from ${T}_{C}$ \ensuremath{\approx} 280 K for $x$ = 1 down to ${T}_{C}$ \ensuremath{\approx} 163 K for $x$ = 2. In the latter compound a re-entrantlike spin-glass state emerges around ${T}_{g}$ \ensuremath{\approx} 70 K. For each composition the isothermal entropy change \ensuremath{\Delta}${S}_{M}$ was derived from magnetic measurements recorded up to 9 T. The obtained \ensuremath{\Delta}${S}_{M}$($T$) curves exhibit a broad and dissymmetric distribution, leading to high values of refrigerant capacity. The impact of the $x$ value on the magnetic and magnetocaloric properties is addressed in detail, taking into account the various spin interactions present in these compounds.

Aristolochia manshuriensis has been used for centuries in Chinese medicinal system for their versatile medicinal uses. Recent studies have revealed two new aristolactames (compound A and B) with γ-lactame ring fused with the phenentherene ring as potent inhibitors of human Cycline Dependent Kinase2 (CDK2). Studies on aristolactames and related compounds claim for their CDK2 inhibition without delineating the involved mechanism and structural basis of interaction. Molecular structural model was used to we propose a structural basis of CDK2 inhibition. We showed that these compounds (A and B) can successfully dock into the inhibitor binding pockets of human CDK2. Predicted binding affinities are comparable to known inhibitors of CDK2. Results were in agreement with the earlier biochemical studies. Hence, suggest that studied compounds A and B can be a promising scaffold for rational design of novel and potential drugs against cancer. Abbreviations CDK2 - cyclin-dependent kinase 2, OLO - Olomoucine, NW1 - Cyclohexylmethyloxy-5-Nitroso-Pyrimidine- 2, 4-Diamine, CMG - 6-O-Cyclohexylmethyl Guanine.

In the course of structurally characterizing previously reported complexes based on the 1,2-bis(dimethylphosphino)ethane)) (dmpe) ligand ([(dmpe)(2)UCl(4)] (1) and [(dmpe)(2)UMe(4)] (2)), we find that adjusting the U/dmpe ratio leads to an unprecedented species. Whereas the use of two or three equivalents of dmpe relative to UCl(4) produces 1 as a blue-green solid, the use of a 1:1 dmpe/UCl(4) stoichiometry yields [(dmpe)(4)U(4)Cl(16)]·2CH(2)Cl(2)·(3·2CH(2)Cl(2)) as a green solid. In turn, 3 is used to prepare a mixed-chelating ligand complex featuring the bidentate ligand 4,4'-dimethyl-2,2'-bipyridine (dmbpy), [(dmpe)(dmbpy)UCl(4)] (4). The measured magnetic susceptibilities for 1-4 trend toward nonmagnetic ground states at low temperatures.

We present the relational database EDULISS (EDinburgh University Ligand Selection System), which stores structural, physicochemical and pharmacophoric properties of small molecules. The database comprises a collection of over 4 million commercially available compounds from 28 different suppliers. A user-friendly web-based interface for EDULISS (available at http://eduliss.bch.ed.ac.uk/) has been established providing a number of data-mining possibilities. For each compound a single 3D conformer is stored along with over 1600 calculated descriptor values (molecular properties). A very efficient method for unique compound recognition, especially for a large scale database, is demonstrated by making use of small subgroups of the descriptors. Many of the shape and distance descriptors are held as pre-calculated bit strings permitting fast and efficient similarity and pharmacophore searches which can be used to identify families of related compounds for biological testing. Two ligand searching applications are given to demonstrate how EDULISS can be used to extract families of molecules with selected structural and biophysical features.

In order to study the structural background of the giant thermal hysteresis observed in the thermopower measurements [1] of the CDW system (NbSe4)10I3, zeroth-order Weissenberg and oscillation photographs were taken at temperatures below Peierls transition. A reversible transformation of the room temperature tetragonal lattice into four symmetricaly equivalent monoclinic domains was observed with the monoclinic angle behaving like an order parameter.

The title compound, C(19)H(30)O(9), was prepared by substitution at the C6 position in 1,2;3,4-di-O-isopropyl-idene-6-O-trifluoro-methane-sulfonyl-d-galactose using sodium eth-oxy-malonate in dimethyl-formamide. The conformation is skew-boat (0)S(2), slightly distorted towards boat B(2,5). The inflexible pyran-ose structure makes the title compound a suitable inter-mediate for further synthetic work by keeping stereogenic carbon atoms safe from inversion. Several short intra-molecular C-H⋯ O contacts may stabilize the conformation of the mol-ecule. Inter-molecular C-H⋯O inter-actions also occur.

Isolation and Characterization Chemical Compounds from the Brak of Garcinia rigida. Garcinia rigida is an Indonesia original plant growing on Sumatera, Java, Kalimantan, and Maluku. Most of its genus have been researched and proven as medicinal plants. Two compounds have been isolated from n-hexane stem-bark of Garcinia Rigida. The two compounds are Stigmasterol (compound A) and a triterpen oleanolic acid (compound B). Keywords: Garcinia rigida, stogmasterol, triterpen, oleanolic acid.

Macrocyclic molecules capable of selective recognition of ionic or neutral guests are of considerable current interest. The design and synthesis of host molecules that contain phosphorus have been developed recently. Typically, the model compound A is modified to the more rigid molecule B which can exist as two exo/endo isomers. B represents a new family of preorganized ligands that can involve the phosphorus group during complexation of various guests. The exo/endo isomerisni was investigated by NMR studies. The complexing properties of B were studied by NMR and extraction method with alkaline and ammonium cations. The complexation constants mainly depend on the molecular geometry and the size of the cavity. The highest Ka constants are obtained with the endo isomer where the P=O bond is directed toward the center of the macrocycle. Complex formation and detailed stereochemical data for A and B will be presented.

Flavone was reduced with sodium bis(2-methoxyethoxy)aluminum hydride (SMEAH) to 1-(2-hydroxyphenyl)-3-phenylpropanol (A) and 1-phenylindan-1, 3-diol (B). Product yields depended on the molar ratio of SMEAH/flavone. When the molar ratio of SMEAH was from 1 to 2 in relation to flavone, the main product was compound A, but at a ratio of more than 3, the rearranged compound B was predominant.

MO CVD processes are promising for reliable and flexible preparation of HTSC films and coatings even on large surfaces of different shape. For DPM complexes of Cu and Y characteristics of decomposition process were obtained. Ba DPM complex was shown to be unstable. To replace this compound a new variety of Ba -diketonate (with alcoxy-ligands) is proposed. This type of compounds for other components of HTSC phases are synthesized and studied. Fluorinated carboxylates are also shown to be prospective for preparation of buffer layers and in lithographic processes in HTSC devices technology.

The synthesis of W3S4Cl4, a layered tungsten thiohalide with a basic structure similar to TiS2 is described. W3S4Cl4 was synthesized from WCl2 and sulfur at 350°C. The X-ray powder diffraction pattern was completely indexed on a small hexagonal unit cell with a=3.336 (I) A and c=5.907 (I) A. Electron diffraction studies revealed a 4 × 4 × 8 supercell, giving the compound a superstructure with a=13.356 A and c=47.29 A . An ordering of the tungsten vacancies which can account for this superstructure is discussed in light of the electron diffraction patterns.

Reaction of phosphite with silyl enol ethers using iodosobenzene/boron trifluoride etherate provides a direct route for the preparation of 2-aryl-2-oxoalkylphosphonates in good yields.

Title compound A (I) and (II) is isolated together with the natural clovane 2β-hydroxyclovan-9-one (II).

An o-bromophenylzinc compound, first prepared in an excellent yield by the reaction of o-bromoiodobenzene with zinc powder in THF, was found to be an efficient synthetic equivalent of o-phenylene 1-anion 2-cation in Pd(0)-catalyzed stepwise cross-coupling reactions, affording unsymmetrically 1,2-disubstituted benzenes with diverse substitution patterns and with a variety of functional groups.

Oxyfunctionalization of esters, 1, by (diacetoxyiodo)benzene and 2,2,6,6-tetramethylpiperidinyl-l-oxy radical produced α-TEMPO esters, 2, which are an efficient unimolecular initiator for the living radical polymerization.