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PubMedDate not supplied

Lipid peroxidation: detection in vivo and in vitro through the formation of saturated hydrocarbon gases.

Saturated, short-chain hydrocarbon gases (ethane, propane, etc.--but not methane) are evolved during the spontaneous lipid peroxidation of mouse tissue slices or homogenates. A relatively-selective increase in either ethane or pentane was observed when either linolenic acid or linoleic acid, respectively, was added to tissue homogenates. When mice were challenged by injection of carbon tetrachloride or cumene hydroperoxide (two agents that induce a lipid peroxidative attack on liver), they exhaled ethane. The gas chromatographic detection and monitoring of hydrocarbon gases can serve as an index of lipid peroxidation in vivo.

Animals↗
PubMed1979

An autoradiographic and immunocytochemical study of the neonatal rat pituitary gland.

Two-day-old female rats were injected with 5 nmole/kg of 6,7-3H-11 beta-methoxy-17-ethylestradiol (R 2858 = moxestrol) and killed one hour later. The animals were decapitated and, the pituitary glands were removed, mounted on tissue holders and frozen in liquified propane. The tissue was then processed for autoradiography according to the thaw-mount technique. At the end of the exposure time, prior to photographic development, some of the tissue was fixed in 10% formalin and then photographically developed for autoradiography. The fixed tissue was subsequently stained immunocytochemically using antibodies to luteinizing hormone or prolactin. Between 10 and 15% of the cells of the pars distalis concentrated the synthetic estrogen or its metabolite. The immunocytochemical procedure revealed that both LH-gonadotrophs and lactotrophs concentrated the steroid. These studies along with earlier studies suggest that the neonatal rat pituitary contains only a small portion of the adult complement of estrogen receptors and that these receptors are dispersed across a number of cell types.

Animals↗
PubMed1994

Ultrastructural studies and immunolocalization of enamel proteins in rodent secretory stage ameloblasts processed by various cryofixation methods.

BACKGROUND: Cryofixation rapidly immobilizes cell and tissue components in their native state, thereby resulting in an ultrastructural preservation very close to the living situation. We have applied this approach to examine the morphology of secretory stage ameloblasts and the distribution of enamel proteins in these cells. METHODS: Molar and incisor tooth germs from newborn mice and/or rats were quickly dissected and divided into segments. The segments were then rapidly frozen using slam, plunge or pressure freezing, freeze-substituted and embedded in Epon. In addition, incisors from older rats were chemically fixed by vascular perfusion and also dehydrated by freeze-substitution. RESULTS: Well-preserved ameloblasts were obtained with all four tissue processing methods. However, slam freezing often showed mechanical damage to the ameloblasts, particularly at the level of the distal portion of Tomes' processes which appeared severed or distorted. Plunging into liquid nitrogen-cooled liquid propane resulted in comparatively less tissue distortion. High pressure freezing gave a relatively higher yield of well-preserved specimens, although displacement of organelles in ameloblasts was sometimes observed, probably resulting from hydrostatic pressure. Minimal ice crystal and mechanical damage was observed in chemically fixed tooth samples processed by freeze-substitution since such specimens are cryoprotected and their examination is not restricted to a surface layer. With all of the above cryopreparation methods, the ultrastructure of well-preserved ameloblasts was, in general, similar to that obtained following conventional chemical fixation, and immunocytochemistry with an anti-amelogenin antibody indicated no profound differences in the distribution of enamel proteins. CONCLUSIONS: These results indicate that, despite some limitations, it is possible to adequately cryofix tooth organs while preserving the architecture of ameloblasts and permitting immunolocalization of enamel proteins. Furthermore, they confirm the general morphology of secretory stage ameloblasts as currently derived from conventional chemical tissue processing.

Ameloblasts↗
PubMed1994

[Antimycobacterial indole derivatives].

1,3-Dinitro-2-(indol-3'-yl)-propanes 3 are synthesized by Michael reaction of nitromethane with the indolylnitroethenes 2. Reaction of the aldehydes 4 and 10 with the benzylamines 12 as well as the reaction of the indolylalkylamines 6a and 9a with the benzaldehydes 11 lead to Schiff bases which are reduced to N-benzyl-(indol-3-ylmethyl)-amines 13 and N-benzyl-(indol-3-ylethyl)-amines 14, respectively; tert amines 16 are synthesized via the formamides 15, amines 18 are prepared according to Mannich. Inhibitory effects on Mycobacterium tuberculosis H 37 Ra are investigated, a structure-activity relationship is discussed.

Anti-Bacterial Agents↗
PubMedDate not supplied

Membrane fusion induced by a lipopeptidic epitope from VP3 capside protein of hepatitis A virus.

Palmitoyl-VP3(110--121) (PVP3) is a synthetic lipopeptide derivative of a continuous epitope from the VP3 capsid protein of hepatitis A virus, and it is highly immunogenic in vivo. We have investigated the interaction of PVP3 with lipid model membranes of varying surface charge. Binding of PVP3 to anionic vesicles of PC/SM/PE/PS; (PC) 1-palmitoyl-2-oleoyl-phosphatidylcholine, (SM) sphingomyelin, (PE) 1,2-dipalmitoyl-phosphatidylethanolamine and (PS) L-alpha-phosphatidyl-L-serine, a composition that mimics the lipid component of natural membranes, was determined by tryptophan fluorescence and quenching experiments. In addition, and given the anionic net charge of the lipopeptide, binding to zwitterionic (PC/SM/PE) and cationic PC/SM/PE/DOTAP (DOTAP) 1,2-dioleoyl-3-trimethylammonium-propane mixtures was also determined. PVP3 binds to all three types of vesicles, but it adopts different forms depending on the electrical charge of the interface. This conclusion is supported by the insertion of PVP3 into lipid monolayers of the same charges spread at the air-water interface. The bound lipopeptide has membrane-destabilizing effects in all three vesicle compositions, as demonstrated by leakage of vesicle contents, whereas lipid mixing only occurs in cationic liposomes. Our results provide useful information for the design of a liposomal system that promotes a direct delivery of the membrane-incorporated immunogen to the immunocompetent cells, potentially increasing the immune response from the host.

Capsid↗
PubMedDate not supplied

Scavenging of reactive oxygen species by the plant phenols genistein and oleuropein.

The plant-derived phenolic compounds genistein and oleuropein are known to exhibit several biological properties, many of which may result from their antioxidant and free radical scavenger activity. In this paper we report the results of a complex study of antioxidant activity of genistein and oleuropein, using electron spin resonance (ESR), chemiluminescence, fluorescence and spectrophotometric techniques. Different reaction systems were applied to study the inhibitory effect of the phenolic compounds studied: (a) the potassium superoxide/18-crown-6 dissolved in DMSO system, which generates superoxide radical (O(2).(-)) and hydrogen peroxide (H(2)O(2)); (b) the Co(II)-EDTA-H(2)O(2) system (the Fenton-like reaction), which generates hydroxyl radical (HO.); (c) 2,2'-azobis(2-amidino-propane)dichloride (AAPH) as the peroxyl radical (ROO.) generator, and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical test. Results showed that genistein and oleuropein decreased the chemiluminescence sum from the O(2).(-) generating system, an inhibitory effect that was dependent on their concentration. These compounds also reacted with ROO radicals and they showed activity about two-fold greater than the standard Trolox. The antioxidant effects were studied at different concentrations and reflected in protection against the fluorescence decay of beta-phycoerythrin (beta-PE), due to ROO. attack on this protein. Using the Fenton-like reaction and the spin trap agent 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), the phenolic compounds examined were found to inhibit DMPO-.OH radical formation in the range 10-90% at concentrations of 0.1 mmol/L to 2 mmol/L. Furthermore, these compounds also inhibited HO.-dependent deoxyribose degradation; about 20% and 60% inhibitions were observed in the presence of 0.5 mmol/L genistein and oleuropein, respectively. It was also demonstrated that genistein had a weaker DPPH radical scavenging activity than oleuropein. Our results confirm good scavenging activity towards O(2).(-), HO. and ROO. and the antioxidant effect of genistein and oleuropein.

Antioxidants↗
PubMedDate not supplied

Anti-oxidant and pro-oxidant behaviour of bucillamine.

Bucillamine (BUC) is used clinically for the treatment of rheumatoid arthritis. Some of the pharmacological action of BUC has been reported as being dependent on the production of reactive oxygen species (ROS). In this paper the reactivity of BUC with superoxide anion radical (O(2) (*-)) generated from potassium superoxide/18-crown-6 ether dissolved in DMSO, hydroxyl radical (HO(*)) produced in the Cu(2+)-H(2)O(2) reaction, peroxyl radical (ROO(*)) from 2,2'-azobis (2-amidino-propane) dichloride decomposition, and singlet oxygen ((1)O(2)) from a mixture of alkaline aqueous H(2)O(2) and acetonitrile, have been investigated. Chemiluminescence, fluorescence, electron paramagnetic resonance (EPR) spin-trapping techniques and the deoxyribose and oxygen radical absorbance capacity towards ROO(*) (ORAC(ROO)) assays were used to elucidate the anti- and pro-oxidative behaviours of BUC towards ROS. The results indicated that BUC efficiently inhibited chemiluminescence from the O(2) (*-)-generating system at relatively high concentrations (0.5-2 mmol/L); however, at lower concentrations (<0.5 mmol/L) the drug enhanced light emission. The behaviour of BUC was correlated with a capacity to decrease the chemiluminescence signal from the Cu(2+)-H(2)O(2) system; scavenging HO(*) was effective only at high concentrations (1-2 mmol/L) of the drug. Bucillamine also prevented deoxyribose degradation induced by HO(*) in a dose-dependent manner, reaching maximal inhibition (24.5%) at a relative high concentration (1.54 mmol/L). Moreover, BUC reacts with ROO(*); the relative ORAC(ROO) was found to be 0.34 micromol/L Trolox equivalents/micromol sample. The drug showed quenching of (1)O(2)-dependent 2,2,6,6-tetramethylpiperidine-N-oxide radical formation from 2,2,6,6-tetramethyl-piperidine (e.g. 90% inhibition was found at 1 mmol/L concentration). The results showed that BUC may directly scavenge ROS or inhibit reactions generating them. However, the drug may have pro-oxidant activity under some reaction conditions.

Anions↗
PubMed2006

Influence of water-miscible organic solvents on kinetics and enantioselectivity of the (R)-specific alcohol dehydrogenase from Lactobacillus brevis.

Using the organic solvents acetonitrile and 1,4-dioxane as water-miscible additives for the alcohol dehydrogenase (ADH)-catalyzed reduction of butan-2-one, we investigated the influence of the solvents on enzyme reaction behavior and enantioselectivity. The NADP(+)-dependent (R)-selective ADH from Lactobacillus brevis (ADH-LB) was chosen as biocatalyst. For cofactor regeneration, the substrate-coupled approach using propan-2-ol as co-substrate was applied. Acetonitrile and 1,4-dioxane were tested from mole fraction 0.015 up to 0.1. Initial rate experiments revealed a complex kinetic behavior with enzyme activation caused by the substrate butan-2-one, and increasing K(M) values with increasing solvent concentration. Furthermore, these experiments showed an enhancement of the enantioselectivity for (R)-butan-2-ol from 37% enantiomeric excess (ee) in pure phosphate buffer up to 43% ee in the presence of 0.1 mol fraction acetonitrile. Finally, the influence of the co-solvents on water activity of the reaction mixture and on enzyme stability was investigated.

Alcohol Dehydrogenase↗
PubMed2005

Scavenging of reactive oxygen species by novel indolin-2-one and indoline-2-thione derivatives.

The antioxidant behavior of a series of new synthesized substituted indoline-2-ones and indolin-2-thiones was investigated in this study using an oxygen radical absorbance capacity assay (ORAC(ROO*-) and 2,2'-azobis(2-amidino-propane) dihydrochloride (AAPH) as the radical generator; system generating superoxide anion radical, O2*- (18-crown-6/KO(2)/DMSO), and the Fenton-like reaction [Co(II) + H(2)O(2) --> Co(III) + HO(*) + HO(-)]. Measurements were done using fluorescence, chemiluminescence methods, and a deoxyribose assay based on the spectrophotometry method, respectively. The results obtained indicated that the examined indoline derivatives had effective activities as radical scavengers and may be considered as an effective source for combating oxidative damage.

Antioxidants↗
PubMed2006

Scavenging of reactive oxygen species by some nonsteroidal anti-inflammatory drugs and fenofibrate.

Ketoprofen and tolmetin are widely used nonsteroidal anti-inflammatory drugs, whereas fenofibrate belongs to a family of hypolipidemic drugs used in the prevention of cardiovascular diseases. The aim of this study was to assess effect of these drugs on reactions generating reactive oxygen species (ROS). The following generators of ROS were used: 18-crown-6/KO(2) dissolved in DMSO as a source of superoxide radical (O(.-)(2), the Fenton-like reaction (Cu/H(2)O(2)) for hydroxyl radical (HO(.)), 2,2'-azobis (2-amidino-propane) dichloride (AAPH) as peroxyl radical (ROO(.)) generator, and a mixture of alkaline aqueous H(2)O(2) and acetonitrile for singlet oxygen ((1)O(2)). Measurements were done using chemiluminescence, fluorescence, and spin-trapping with 2,2,6,6-tetramethylpiperidine combined with electron spin resonance spectroscopy (ESR), and a deoxyribose assay based on the spectrophotometry. The results obtained demonstrated that all tested drugs were active against O(.-)(2). There was a clear ranking of drug inhibition effects on chemiluminescence from the O(.-)(2) system: ketoprofen > tolmetin > fenofibrate. The examined compounds inhibited the HO(.)-dependent deoxyribose degradation and scavenged the ROO(.) concentration dependently with an order of potencies similar to that of the superoxide radical system. Hence, these results indicate that the studied drugs show broad ROS scavenging property and, as a consequence, might decrease tissue damage due to the ROS and thus to contribute to anti-inflammatory therapy.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Aerobic biodegradation of N-nitrosodimethylamine (NDMA) by axenic bacterial strains.

The water contaminant N-nitrosodimethylamine (NDMA) is a probable human carcinogen whose appearance in the environment is related to the release of rocket fuel and to chlorine-based disinfection of water and wastewater. Although this compound has been shown to be biodegradable, there is minimal information about the organisms capable of this degradation, and little is understood of the mechanisms or biochemistry involved. This study shows that bacteria expressing monooxygenase enzymes functionally similar to those demonstrated to degrade NDMA in eukaryotes have the capability to degrade NDMA. Specifically, induction of the soluble methane monooxygenase (sMMO) expressed by Methylosinus trichosporium OB3b, the propane monooxygenase (PMO) enzyme of Mycobacterium vaccae JOB-5, and the toluene 4-monooxygenases found in Ralstonia pickettii PKO1 and Pseudomonas mendocina KR1 resulted in NDMA degradation by these strains. In each of these cases, brief exposure to acetylene gas, a suicide substrate for certain monooxygenases, inhibited the degradation of NDMA. Further, Escherichia coli TG1/pBS(Kan) containing recombinant plasmids derived from the toluene monooxygenases found in strains PKO1 and KR1 mimicked the behavior of the parent strains. In contrast, M. trichosporium OB3b expressing the particulate form of MMO, Burkholderia cepacia G4 expressing the toluene 2-monooxygenase, and Pseudomonas putida mt-2 expressing the toluene sidechain monooxygenase were not capable of NDMA degradation. In addition, bacteria expressing aromatic dioxygenases were not capable of NDMA degradation. Finally, Rhodococcus sp. RR1 exhibited the ability to degrade NDMA by an unidentified, constitutively expressed enzyme that, unlike the confirmed monooxygenases, was not inhibited by acetylene exposure.

Aerobiosis↗
PubMed2001

Drugs of abuse in a non-conventional sample; detection of methamphetamine and its main metabolite, amphetamine in abusers' clothes by HPLC with UV and fluorescence detection.

In this paper, we report the detection of methamphetamine and its major metabolite, amphetamine, in garments belong to known-abusers. These compounds were extracted from the textile using a mixture of chloroform:propan-2-ol (3:1, v/v), derivatized with 4-(4,5-diphenyl-1H-imidazol-2-yl) benzoyl chloride and separated using a reversed-phase high-performance liquid chromatography. The derivatives were detected by measuring either fluorescence at 440 nm or absorbance at 330 nm. By using 1-methyl-3-phenyl propylamine as an internal standard, calibration curves of spiked textile samples were linear over a wide range with correlation coefficients of 0.997 or better. Detection limits at a signal-to-noise ratio of 3 were less than or equal to 37.3 and 0.4 pg on column for the high-performance liquid chromatography-ultraviolet and -fluorescence detection methods, respectively. Intra- and inter-day variations at high and low concentrations (n > or = 3) were < or =12.7%. The developed methods were successfully applied to the determination of methamphetamine and amphetamine in clothes samples belong to abusers.

1-Propanol↗
PubMed1976

Mass spectral identification of the metabolites of alpha,alpha-dimethyl-4-(alpha,alpha,beta,beta-tetrafluorophenethyl)-benzylamine (MK-251), a novel antiarrhythmic agent, in various species.

The identification of a number of metabolites of the novel antiarrhythmic agent, alpha,alpha-dimethyl-4-(alpha,alpha,beta,beta-tetrafluorophenethyl)benzylamine (MK-251), is presented. The compound is extensively metabolized by dog, monkey, baboon and man. Similar metabolic profiles were obtained for all species. Isolation and purification were accomplished by solvent extraction and chromatographic (column, gas and thin-layer) procedures. Gas chromatography, derivatization, infrared, nuclear magnetic resonance and particularly combined gas chromatography low and high resolution mass spectrometry techniques were employed to characterize the metabolites. The major urinary and plasma metabolites were identified as 2-[4-(alpha,alpha,beta,beta-tetrafluorophenethyl)phenyl]-2-propanol and its glucuronide conjugate. Other metabolites characterized were: the N-glucuronide of MK-251; 2-[4-(alpha,alpha,beta,beta-tetrafluorophenethyl)phenyl]propene; 2-nitro-2-[4-)alpha,alpha,beta,beta-tetrafluorophenethyl)phenyl]propane; alpha,alpha-dimethyl-4(alpha,alpha,beta,beta-tetrafluorophenethyl)benzyl methyl ether; and 4-(alpha,alpha,beta,beta-tetrafluorophenethyl)acetophenone. The 0-methyl ether metabolite represents the first instance of in vivo alkylation of a tertiary alcohol. Tentative identification was made for the N-hydroxy analog of MK-251 and for the glycol analog of 2-[4-(alpha,alpha,beta,beta-tetrafluorophenethyl)phenyl]-2-propanol. The observed pharmacological response appears to result mainly from MK-251 and not from the four metabolites.

Amines↗
PubMed1981

Mass spectrometry of 2-substituted 5-nitro-2-furyl thiazoles. Identification of microsomal nitroreduction products by electron impact mass spectrometry.

The electron impact mass spectral fragmentation of nitro heterocyclic carcinogens N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide, 2-amino-4-(5-nitro-2-furyl)thiazole, 2-methyl-4-(5-nitro-2-furyl)thiazole and 2-methylamino-4-(5-nitro-2-furyl)thiazole were studied. The molecular ions undergo two modes of cleavage: one giving [M-84]+ ions which include the 2-substituted thiazole ring, while the other gives rise to the fragment [M-74]+ ions. The products of anaerobic microsomal nitroreduction of 2-methyl-4-(5-nitro-2-furyl)thiazole were isolated and purified by high-pressure liquid chromatography. The metabolites undergo different fragmentation patterns compared to the parent nitro analogs. Metabolites from anaerobic enzymatic reduction showed identical gas chromatographic, high-pressure liquid chromatographic and thin-layer chromatographic properties to the chemically synthesized material. The metabolites were identified as 1-(2-methyl-4-thiazolyl)-3-cyano-1-propenone and 1-(2-methyl-4-thiazolyl)-3-cyano-1-propane by mass spectral fragmentation pattern.

Animals↗
PubMed2001

Effects of phosphoprotein phosphatase inhibitors (phenylarsine oxide and cantharidin) on Tetrahymena.

The effects of phenylarsine oxide (PAO) (phosphotyrosine phosphatase inhibitor) and cantharidin (serine/threonine phosphatase [PP2A] inhibitor) treatments were analysed on the synthesis of phospholipids and glycolipids, and on the cytoskeletal elements (F-actin and tubulin containing structures) of Tetrahymena pyriformis. Both phosphatase inhibitors reduced the amount of incorporated 32P of the whole phospholipid content, but the ratio of phosphatidylserine (PS) and phosphatidylcholine (PC) to the total phospholipid content increased. Both treatments influenced the phosphatidylinositol (PI) system. These inhibitors also influenced the incorporation of palmitic acid into the phospholipids: in general PAO decreased, whereas cantharidin increased the amount of incorporated palmitic acid; 1 microM cantharidin significantly increased the labelling of PE and PA. The incorporation of mannose and glucosamine was influenced differently by PAO and cantharidin treatments: the latter elevated, while PAO decreased the labelling of glycolipids with these sugars. The effects of these treatments were visible also in the case of confocal scanning laser microscopic (CSLM) images: after treatments with both inhibitors, the F-actin containing cortical elements were destroyed, but the tubulin containing ones (longitudinal and transversal microtubules, oral apparatus and deep fibres) did not display significant alterations. The different effects of phosphatase inhibitors were visible also on the scanning electron microscopic (sEM) images: cantharidin treatments (1 microM) decreased the amount of dissolved membrane lipids after chemical dehydration of the cells with 2, 2-dimethoxy propane (DMP), but in the case of treatments with 10 microM, the surface pattern of cells was similar to the controls. On the other hand, after PAO treatments the surface pattern of Tetrahymena showed significant alterations. Both phosphatase inhibitors inhibited the phagocytotic activity of the cells. On the basis of present experiments we suppose that these treatments are able to influence signalling systems (e.g. PI) of Tetrahymena, and also the structure of the cytoskeleton and the functions (e.g. phagocytosis) which are connected with skeletal elements.

Actins↗
PubMed2003

Alteration of the substrate specificity of benzoylformate decarboxylase from Pseudomonas putida by directed evolution.

Alteration of the substrate specificity of thiamin diphosphate (ThDP)-dependent benzoylformate decarboxylase (BFD) by error-prone PCR is described. Two mutant enzymes, L476Q and M365L-L461S, were identified that accept ortho-substituted benzaldehyde derivatives as donor substrates, which leads to the formation of 2-hydroxy ketones. Both variants, L476Q and M365L-L461S, selectively catalyze the formation of enantiopure (S)-2-hydroxy-1-(2-methylphenyl)propan-1-one with excellent yields, a reaction which is only poorly catalyzed by the wild-type enzyme. Different ortho-substituted benzaldehyde derivatives, such as 2-chloro-, 2-methoxy-, or 2-bromobenzaldehyde are accepted as donor substrates by both BFD variants as well and conversion with acetaldehyde resulted in the corresponding (S)-2-hydroxy-1-phenylpropan-1-one derivatives. As deduced from modeling studies based on the 3D structure of wild-type BFD, reduction of the side chain size at position L461 probably results in an enlarged substrate binding site and facilitates the initial binding of ortho-substituted benzaldehyde derivatives to the cofactor ThDP.

Binding Sites↗
PubMed2005

Creating space for large secondary alcohols by rational redesign of Candida antarctica lipase B.

The active site of Candida antarctica lipase B (CALB) hosts the catalytic triad (Ser-His-Asp), an oxyanion hole and a stereospecificity pocket. During catalysis, the fast-reacting enantiomer of secondary alcohols places its medium-sized substituent in the stereospecificity pocket and its large substituent towards the active-site entrance. The largest group to fit comfortably in the stereospecificity pocket is ethyl, and this restricts the number of secondary alcohols that are good substrates for CALB. In order to overcome this limitation, the size of the stereospecificity pocket was redesigned by changing Trp104. The substrate specificity of the Trp104Ala mutant compared to that of the wild-type lipase increased 270 times towards heptan-4-ol and 5500 times towards nonan-5-ol; this resulted in the high specificity constants 1100 and 830 s(-1) M(-1), respectively. The substrate selectivity changed over 400,000 times for nonan-5-ol over propan-2-ol with both Trp104Ala and the Trp104Gln mutations.

Alcohols↗
PubMed2003

Square-planar coordinated polyanions of palladium, platinum, and gold stannaborate [SnB11H11]2- coordination chemistry.

The tetrasubstituted polyanions of platinum, palladium, and gold [M(SnB(11)H(11))(4)](x-) (x=6, M=Pd, Pt; x=5, M=Au) have been prepared and characterized by single-crystal X-ray diffraction, elemental analysis, IR, Raman, (11)B, and (119)Sn heteronuclear NMR spectroscopy. In the case of the platinum derivative [Bu(3)MeN](6)[Pt(SnB(11)H(11))(4)] (2) (119)Sn Mössbauer spectroscopy has been carried out. The isolated salts are stable towards moisture and air and the complexes 2 and 3 were treated with 1,3-bis(diphenylphosphino)propane (dppp) to give the respective substitution products [Bu(3)MeN](2)[(dppp)M(SnB(11)H(11))(2)] (M=Pd, Pt).

Journal Article↗