Structure of Compounds in Systems P-O-N and Me-P-N

Abstract

In resent years phosphorus-nitrogen compounds containing oxygen or metal have caused increasing interest. Structural basis of these compounds is formed by variously interconnected tetrahedra with phosphorus atoms located in the centre with nitrogen atoms situated on tetrahedra tops. Part of the nitrogen atoms can be substituted by those of oxygen.     

Some developments in the chemical direct oxygen determination

This paper discusses modifications of the direct determination of oxygen in organic compounds by reduction with carbon. Two versions are considered, (a) a microscale method for compounds containing metals, phosphorus or boron, and including automatic non-aqueous carbon dioxide titration, and (b) a manometric method capable of analysing samples containing traces of oxygen down to 5ppm.     

Siloxane Compounds of the Transition Metals

Heterosiloxanes of transition metals contain the characteristic grouping Si? O? X; in the compounds known so far, X may be Au, Zn, Cd, Hg, Ti, Zr, Hf, V, Nb, Ta, Cr, U, Re, Fe, Co, Ni, or Pt. Most of these compounds are obtained from silanols, metal silanolates, acyloxysilanes, disiloxanes, or alkoxysilanes, i.e. from compounds that already contain an Si? O bond. The transition metal may be introduced e.g. as a halide, as an organometailic compound, as an alkoxy compound, or as an oxide. Heterosiloxanes are also formed on reaction of many silicon compounds that do not contain oxygen with transition metal compounds containing oxygen. Some of these compounds, e.g. some titanosiloxanes, are very stable, whereas others decompose explosively. Oligomeric and polymeric heterosiloxanes exist in addition to the monomeric compounds.     

Paradigms and paradoxes: organic thermochemistry without hydrogen: carbon oxides and nitrides

All organic compounds contain carbon. Most contain hydrogen. This brief study discusses the enthalpy of formation of a collection of organic compounds containing only oxygen or nitrogen accompanying the carbon.     

Surface activity and fluorite flotation with myristic acid derivatives containing oxygen and sulphur atoms

Surface tension isotherms and fluorite flotation were studied in systems containing myristic acid derivatives in which carbon atoms in the hydrocarbon skeleton were partly replaced by oxygen and/or sulphur atoms. The location of the oxygen and sulphur atoms affects significantly compound hydrophobicity, adsorption at the air/water interface and fluorite flotation. The most effective collectors were the compounds with one oxygen or sulphur atom close to the carboxylic group.     

新型含硫(氧)肟醚衍生物的合成、杀虫活性及其结构活性关系研究

通过1-芳基含硫(氧)酮肟与相应的拟除虫菊醇卤化物在氢氧化钠和相转移催化剂条件下反应或1-芳基含硫(氧)酮肟与相应的拟除虫菊醇卤化物的三乙基季胺盐在氢氧化钠条件下反应, 合成了1-芳基含硫(氧)酮O-苄基肟醚C1～C96共96个化合物. 它们的结构经质谱, 1H NMR, IR和元素分析确证. 生物活性测定结果表明, 该类化合物对鳞翅目和同翅目害虫表现出显著活性, C74和C93对粘虫、叶蝉的活性[LC50/(mg•L－1)]分别为1.4, 0.63和0.31, 1.2. 优于对照药氰戊菊酯.     

Doubly charged ion mass spectra: V—Oxygen containing hydrocarbons

Doubly charged ion mass spectra were obtained for 46 low molecular weight oxygen containing compounds. A double focusing Hitachi RMU-7L mass spectrometer, operated at 3.2 kV accelerating voltage, was used to measure spectra for aliphatic alcohol, ketone, ether, aldehyde, ester and acid molecules, as well as several aromatic oxygen containing compounds. In general, the spectra were dominated by fragment ions which resulted from extensive H loss and C? C bond rupture as well as O elimination from the doubly charged molecular ions. Total product ion intensities from doubly charged ion spectra of aliphatic oxygen containing compounds were approximately 1% of the corresponding total ion intensity in the benzene doubly charged ion spectrum. Appearance energies for forming prominent doubly charged molecular and fragment ions were determined. Measured values ranged from 26 to 45 eV. A geometry optimized quantum mechanical SCF treatment was used to compute the energies, charge densities and structures for several of these oxygen containing doubly charged ions.     

Phosphorylated chitin as a chemically modified polymer for ecofriendly corrosion inhibition of copper in aqueous chloride environment

Research on Chemical Intermediates - Heterocyclic organic molecules containing oxygen, nitrogen or sulfur are generally used as inhibitors for corrosion protection of copper. These compounds form...     

Etude thermochimique de quelques benzoates de cuivre(II) solvates

Some compounds of copper(II) benzoate solvated by ligands containing either oxygen (water, alcohol, dioxan) or nitrogen (amines, amides) or both, have been prepared. The thermal decomposition has been studied by TG and ATD methods. The standard enthalpies of formation have been determined and verified by some estimation methods.     

Approaches to Total Synthesis of Heterocyclic Steroidal Systems

In heterocyclic steroids the carbon atoms of the steroid skeleton (positions I to 17) are replaced in part by hetero atoms. The term generally denotes compounds containing one or two nitrogen, oxygen, and/or sulfur atoms. The part of the molecule containing the hetero atom is either introduced as a preformed unit or is constructed by stepwise synthesis. The examples given in the present article contain the hetero atoms in ring A, ring B, between rings A and B, and/or between rings C and D.     

Chemiluminescence-HPLC for the assay of guanidino compounds

A chemiluminescence-HPLC system for the assay of serum guanidino compounds was established. In this study, we found that lucigenin added to the reaction mixture containing guanidino compounds and alkaline-ninhydrin reagent resulted in strong chemiluminescence. The lucigenin chemiluminescence was not derived from fluorescent derivatives of guanidino compounds or ninhydrin. The interaction of guanidino compounds and ninhydrin under alkaline conditions produced reactive oxygen species. We applied this phenomenon to the microanalysis of guanidino compounds.     

水溶性金属卟啉应用于催化反应的研究进展

综述了水溶性金属卟啉作为催化剂应用于均相或非均相的催化反应的研究进展,重点介绍了水溶性金属卟啉在水或水与有机溶剂混合介质中催化底物氧化反应的催化性能,其中包括烷烃的羟基化,烯烃的环氧化,含氧、含硫及含氮化合物的氧化反应.另外水溶性金属卟啉还可用于催化Suzuki-Miyaura反应、氧化偶联反应、C=C氧化断裂反应等.水溶性金属卟啉催化剂具有水溶性、催化效率高、反应条件温和等优点,因此将在催化反应特别是氧化反应中得到更广泛的应用.     

微波在合成六元杂环化合物中的应用

对微波技术在合成六员杂环化合物中的应用做了概述:(1)含氧六员杂环化合物;(2)含氮六员杂环化合物。     

The detection of oxygen in organic compounds with potassium tetrathiocyanato-cobaltate(II)

A new micro or Semimicro test for detection of oxygen in organic compounds is based on the blue colour given on treatment with a solid potassium thiocyanatocobaltate reagent. The test was checked with ca. 500 compounds containing various functional groups; very few anomalous reactions were observed.     

Adsorption of methyl red on sterchamol

The mode of retention of methyl red on Sterchamol is studied by the adsorption of compounds containing some of the functional groups active for hydrogen bonding in the methyl red molecule. It is shown that two types of adsorbing centres exist on the Sterchamol surface. An adsorbate with an oxygen or nitrogen electron-donor atom in its molecule deactivates only one type of centre. Both electron donors are present in a methyl red molecule, allowing both types of active sites to be deactivated by this adsorbate.     

Selected β2-, β3- and β2,3-Amino Acid Heterocyclic Derivatives and Their Biological Perspective

Heterocyclic moieties, especially five and six-membered rings containing nitrogen, oxygen or sulfur atoms, are broadly distributed in nature. Among them, synthetic and natural alike are pharmacologically active compounds and have always been at the forefront of attention due to their pharmacological properties. Heterocycles can be divided into different groups based on the presence of characteristic structural motifs. The presence of β-amino acid and heterocyclic core in one compound is very interesting; additionally, it very often plays a vital role in their biological activity. Usually, such compounds are not considered to be chemicals containing a β-amino acid motif; however, considering them as this class of compounds may open new routes of their preparation and application as new drug precursors or even drugs. The possibility of their application as nonproteinogenic amino acid residues in peptide or peptide derivatives synthesis to prepare a new class of compounds is also promising. This review highlights the actual state of knowledge about β-amino acid moiety-containing heterocycles presenting antiviral, anti-inflammatory, antibacterial compounds, anaplastic lymphoma kinase (ALK) inhibitors, as well as agonist and antagonists of the receptors.     

Determination of oxygen,fluorine and boron by 14-MeV INAA: A case of multiple interferences

Oxygen and fluorine have been simultaneously determined by 14-MeV INAA in samples containing boron. Both boron and fluorine can cause serious interferences in the determination of oxygen. The fluorine and boron interference corrections for oxygen determination have been determined to be 0.43±0.01 and 0.0832±0.0017 apparent g oxygen per g of fluorine and boron, respectively, for our system. Boron can be determined in the same sample by a second irradiation. Mutual interferences have been evaluated and the procedure has been applied to NIST SRM and several other compounds.     

The semi-micro determination of fluorine,chlorine, and nitrogen in organic compounds

The organic compounds are fused with sodium in a nickel bomb in the usual way and the fluoride, chloride, and cyanide ions produced are determined. The method cannot be used to determine nitrogen in organic compounds containing oxygen since, in such cases, some of the nitrogen is converted to cyanate ion.     

Carbohydrates Containing Nitrogen or Sulfur in the “Hemiacetal” Ring

In 5-amino-5-deoxy-and 5-thioaldoses, a 6-membered hemiacetal ring can be formed by incorporation of a nitrogen or sulfur atom into the ring instead of the oxygen present in pyranoses. In the case of 5-(N-acylamido) -5- deoxyaldoses, the nucleophilic strength of the amide grouping is lowered, with the result that ring closure occurs only when sterically favored, or when a side reaction with formation of furanose is not possible. On the other hand, 5-amino-5-deoxyaldoses containing a free amino group readily from 6-membered “hemiacetal” rings. The resulting piperidinoses possess properties that are unusual in sugars, since they contain the 2-hydroxypiperidine ring system. Piperidinoses are stable to alkalis and labile to acids; they rearrange in the presence of acids to give Amadori compounds, or lose three molecules of water to give derivatives of β-hydroxypyridines. Owing to the high reactivity of the mercapto group, 5-thioaldoses from only sugars with rings containing sulfur, the behavior of which resembles that of the oxygen analogues. 4-Amino-4-deoxy- and 4-thioaldoses can form 5-membered rings containing nitrogen and sulfur.