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A new isoflavone, 4‘,5,7-trihydroxy-6,8-dimethylisoflavone (1), and a new sesterterpenoic acid (2), together with five known compounds, lichexanthone (3), (−)-pinoresinol (4), betulinic acid, palmitic acid, and β-sitosterol, were isolated from a dichloromethane extract of the branches of Henriettella fascicularis. Their structures were established by extensive spectroscopic methods. An attempt to determine the absolute stereochemistry of (2E,6S)-6-[(1R,5Z,3aS,9R,10Z,12aR)-1,2,3,3a,4,7,8,9,12,12a-decahydro-9-hydroxy-3a,6,10-trimethylcyclopentanocycloundecen-1-yl]-2-methylhept-2-enoic acid (2) was performed by single-crystal X-ray analysis, using Cu Kα radiation. Compound 1 showed significant competitive binding to estrogen receptor β and moderate antiestrogenic activity with cultured Ishikawa cells.

Four new sesquiterpenoid derivatives named mansonones N (1), O (2), P (3), and Q (4) were isolated from a dichloromethane extract of the heartwood of Mansonia gagei, a plant used in folk medicine in Thailand. Their structures were resolved on the basis of spectrometric data interpretation and the single-crystal X-ray analysis of 1 and 2.

Abstract:: We study finite-size effects in the self-organized critical forest-fire model by numerically evaluating the tree density and the fire size distribution. The results show that this model does not display the finite-size scaling seen in conventional critical systems. Rather, the system is composed of relatively homogeneous patches of different tree densities, leading to two qualitatively different types of fires: those that span an entire patch and those that do not. As the system size becomes smaller, the system contains less patches, and finally becomes homogeneous, with large density fluctuations in time.

This report concerns the organometallic chemistry of niobium based on a macrocyclic ligand. To this purpose, the (meso-octaalkylporphyrinogen)niobium(V) complex [(η⁵:η¹:η⁵:η¹-Et8N4)NbCl], 2, has been used as an appropriate starting material. The ionization of the Nb−Cl bond by the use of AgSO3CF3 gave a bifunctional acid−base system with an increased acidity of the metal center in [(η⁵:η¹:η¹:η¹-Et8N4)Nb(THF)(O3SCF3)], 3. The alkylation of 2 with LiMe gave a quite stable Nb(V) organometallic derivative [(η⁵:η¹:η¹:η¹-Et8N4)Nb−Me], 4, which undergoes a migratory insertion reaction with Bu^tNC leading to an η²-iminoacyl derivative [(η⁵:η¹:η¹:η¹-Et8N4)Nb(Bu^tNC)(η²-C(Me)&dbd;NBu^t)], 6 (νC&dbd;N, 2217 and 1736 cm^-1). Two steps of the reaction have been identified. An attempt to functionalize the Nb&dbd;O in [(η⁵:η¹:η¹:η¹-Et8(C4H2N)3(p-MeC5H2N)Nb&dbd;O], 7, by the use of LiMe led, on the contrary, to [(η¹:η¹:η¹:η¹-Et7(CH-Me)(C4H2N)3(p-MeC5H2N)NbOLi(THF)3], derived from the metalation of one of the meso-ethyl groups in 9. While X-ray analysis provided information on the solid state structures of 3, 4, 6, and 9, NMR studies allowed us to establish a relationship between the bonding mode of the porphyrinogen in the solid state and in solution.

Summary.: Total knee arthroplasty has become a routine procedure in surgery. Deep infections have an incidence of 2–5 %. Major risk factors are large prostheses, rheumatoid arthritis, diabetes mellitus and postoperative wound-healing complications. In large soft-tissue defects with skin necrosis, local wound care shows poor results, especially if loosening of the prosthesis and necrosis of the patellar ligament are evident. In these cases, no standard surgical therapy has been developed yet. Thus, we consider meticulous débridement with synovialectomy to be mandatory. Exchange of the prosthesis may be necessary. Soft-tissue coverage ought to be performed with a gastrocnemius muscle flap covered with a split-thickness skin graft. In the last three years, 11 patients with large soft-tissue defects and necrosis of the ligament were treated according to this concept. In all cases the muscle flap healed primarily and soft tissue coverage was excellent. Two patients who underwent single-stage removal and reimplantation of the prosthesis showed reinfections of the prosthesis. Reconstruction of the ligament was performed with the flap tendon. The patients with two-stage removal and reimplantation of the prosthesis and those who retained their implants had a good functional outcome. The gastrocnemius muscle flap provides easy and reliable soft-tissue reconstruction in large defects. In our patients a two-stage operation for reimplantation of the prosthesis was superior to a single-stage procedure. The reconstructed ligament should be reinforced with autologous material to prevent a secondary rupture. Early reconstruction with sufficient soft-tissue coverage and reconstruction of the ligament offers the patient the best chances of obtaining a good functional result and prevents arthrodesis or amputation. In addition, reconstructive surgery reduces the length of hospital stay and costs.

Summary 112 patients with a history of proven myocardial infarction were studied. 17 had overt diabetes mellitus. In the remaining 95 patients carbohydrate tolerance and the insulin secretory response to i.v. glucose were studied. 45% of all patients had pathological i.v. glucose tolerance-tests (KG<1.00) and 17% had borderline results (KG 1.00–1.20).

The structural phase transitions between the intercalated and the non-intercalated phases of the layer structure compound n-decylammoniumchloride and n-hexylammoniumchloride have been studied via proton-14N and proton-35Cl nuclear quadrupole double resonance. The results have been related to an order-disorder model of the alkylammonium chains. The temperature dependence of the order parameters of the -NH3 head groups has been determined.

Summary Mutation induction was investigated in wild-type haploid yeastSacchaomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency.

The coordination properties of [(η⁵-C5H5)Co{PR2(O)}3]^- (R = OEt (LOEt^-), Et (LEt^-)) toward Zr(IV) have been investigated and compared to related cyclopentadienyl complexes. Addition of 2 equiv of LOEt^- to [ZrCl4(THF)2] yields labile [Zr(LOEt)2Cl2] (2), which undergoes Arbuzov dealkylation to yield a dinuclear, seven-coordinate complex 1. Reaction of 2 with MeLi yields the metathesis product LiLOEt. Addition of 2 equiv of AgOTos to 2 affords octahedral [Zr(LOEt)2](OTos)2 (3). Reaction of [ZrCpCl3] with LOEt^- leads to Cp^- displacement to give [ZrLOEtCl3] (4). Addition of 2 equiv of LEt^- to [ZrCl4(THF)2] yields octahedral [Zr(LEt)2](Cl)2 (5). Compounds 1, 3, 4, and 5 have been characterized by X-ray crystallography.

Solubilization of the highly insoluble polymeric ZrCl4 is achieved using 1,2,4,5-Me4C6H2 (durene) as a carrier in a halogenated solvent, such as CH2Cl2, CHCl3, 1,2-Cl2C2H4, or o-Cl2C6H4. Solubilization can reach the level of 40 g of ZrCl4 in 100 mL of CH2Cl2 using an equimolar amount of durene. This is a very successful approach to making available soluble ZrCl4 in a noncoordinating solvent. The solubilization occurs via the formation of a η⁶-arene complex, which has been structurally characterized in the form of the hexamethylbenzene derivative [(η⁶-Me6C6)Zr2(μ-Cl)3Cl5] (3). This complex is in equilibrium, as revealed by the ¹H NMR spectrum in CH2Cl2, with free C6Me6 and a complex (4) which contains a higher Zr/C6Me6 ratio. A careful analysis of the CH2Cl2 solution, containing originally ZrCl4 and durene, showed that durene underwent transformation to C6Me5H and C6Me6. These species have been trapped, bonded to zirconium in complex [(η⁶-C6Me5R)Zr2(μ-Cl)3Cl5] (2, R = H, 50%; R = Me, 50%), which has been structurally characterized. The methyl redistribution reaction in CH2Cl2 can result in the inconvenient formation of byproducts derived from the Zr-assisted Friedel−Craft reaction of CH2Cl2 on the arene. The intermediate of such a reaction has been isolated as [C6Me6CHCl2]⁺[Zr2Cl9]^- (5), whose X-ray structure is available. In order to avoid the intervention of the solvent and to speed up the reaction, the ZrCl4 rearrangement of methylbenzenes was carried out in neat hydrocarbon at 90 °C for 6 h. This rearrangement has a number of peculiarities:  (i) unlike the original Jacobsen reaction, it involves intermolecular methyl transfer; (ii) it reaches an equilibrium of methyl distribution; and (iii) it is catalytic in zirconium. The very high stability of 3 accounts for the isolation of the same compound derived from the ZrCl4-assisted trimerization of 2-butyne in n-hexane.

An organic nonlinear optical crystal, 5-nitro-2-thiophenecarboxaldehyde-4-methylphenylhydrazone (NTMPH), has been prepared and investigated with regard to polymorphism, growth, and characterization of the structural and physical properties. Recrystallization of NTMPH in various solvents under different conditions showed the existence of three crystalline phases, red greenish plates (NTMPH−I) in space group P21/n, red orange prisms (NTMPH−II) in space group Pna21, and black needle (NTMPH−III) in space group P21/n. The crystal structures of NTMPH showed that three different intermolecular forces dominate the stabilization of one- or two-dimensional structures (called secondary structures in this work) of the three phases of the NTMPH crystals, namely the hydrogen bonding, dipole−dipole interactions, and the van der Waals forces for NTMPH−I, −II, and −III crystals, respectively. The thermal analysis showed that within the trimorphs the NTMPH−I crystal has the lowest thermodynamic stability with the lowest melting point and enthalpy, but NTMPH−II and −III crystals possess a higher thermodynamic stability and are called thermodynamic phases. The NTMPH−I crystal is easily crystallized in most conditions and is called a kinetic phase, whereas NTMPH−II and −III are crystallized with a higher supercooling (equal to a higher chemical potential), which also means that higher energy barriers for the nucleation of NTMPH−II and −III must be overcome. Since crystal structures cannot be designed precisely based on the molecular properties, especially for flexible molecules, the finding and selective growth of interesting polymorphic crystals is an essential step for the development of highly active nonlinear optical materials.

We injected mice with human serum once or several times and investigated the morphological changes in the lymphatic system and the formation of antibody for 70 days. As to its cellular composition, the antibody-forming tissue reacted in two phases. The formation of antibody was also biphasic. Microscopically in the first stage the number of small lymphocytes diminished and the number of large lymphocytes, small reticulum cells and lymphatic nodules increased. In the second phase, there was an increase in the number of large reticulum cells, immature plasma cells and mature plasma cells.

Zusammenfassung An Hand einer fast 30jährigen Erfahrung unserer Klinik wird die Zweckmäßigkeit einer Wachstation—sie wurde Anfang der 30er Jahre hier vonKirschner eingeführt—gezeigt, die sich von den sonst häufig üblichen reinen Postoperativen—gezeigt, die sich von den sonst dadurch unterscheidet, daß sie dieschwersten Fälle aller chirurgischen Kategorien umfaßt. Es kommen dabei 4 Personengruppen in Frage: 1. dieFrischoperierten der Schädel-, Thorax-und großen Bauchchirurgie sowie Sonderfälle. 2. Alleschwer akut Erkrankten, die einer besonderen Beobachtung und Behandlung bedürfen, sowie alle akuten unklaren Krankheitsbilder. 3. Dieschweren Unfälle (Bewußtlosigkeit, Schock, Fettembolie). 4. Sonderfälle, die einebesondere Belastung darstellen, wie Tetanus, schwerer Basedow, Verbrennungen und Suicid-Fälle.

A novel bismuthates(III) complex, (C6H14N)4[BiCl6]Cl·2H2O, was synthesized and characterized by X-ray diffraction and FT-IR spectroscopy. Its structure consists of protonated cyclohexylamine cations, discrete [BiCl6]3−anions, chlorine anions and water molecules. The chlorobismuthate(III) anions alternate with the water molecules O1 as to form hydrogen-bonded helical chain running along the crystallographic b-axis with a period of 17.622 Å. These components are connected into a three-dimensional network via hydrogen bonds. In addition, the ground state geometry, vibrational wavenumbers and Natural bond orbital (NBO) analysis were studied by means of density functional theory (DFT/B3LYP) with LanL2DZ basis set. Theoretical results are within the range of the experimental data. The NBO analysis reveals the influence of the N–H…O, N–H…Cl and OH…Cl intermolecular interactions on crystal packing. Moreover, the electrochemical behavior of this complex was investigated in DMSO by cyclic voltammetry (CV).

Summary The haemodynamic effects of intravenous injections of furosemide and ethacrynic acid were studied in 12 patients during rest and excercise.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.