Conjugates of polyhedral boron compounds with carbohydrates

Conjugates of β-lactosylamine derivatives bearing terminal amino groups in aglycon with ortho-carboranylacetic acid were synthesized. Five glycoconjugates with spacers of different length (from 9 to 18 atoms) and hydrophilicity containing di-, tri-, and pentapeptide fragments constructed of glycine and serine residues and spacers incorporating ethylenediamine and tartaric acid or tertiary amine residues were prepared Dedicated to the memory of outstanding chemist and biochemist V. N. Shibaev. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2033–2036, October, 2007.     

Synthesis and structure of the new binuclear complex η5-C5H5(CO)2Fe-η1-C5H4(CO)2Fe-CH3

Conclusions The new binuclear complex ⁵-C₅H₅(CO)₂Fe-¹-C₅H₄(CO)₂Fe-CH₃ was synthesized. Its structure was established by x-ray crystallographic analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 437–440, February, 1986.     

Infrared Spectroscopy and Structure of Trigonal Zirconium Orthophosphates with Lanthanides and Actinides

Binary zirconium orthophosphates R_1/3Zr₂(PO₄)₃ and M_1/4Zr₂(PO₄)₃, where R = Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu; M = Th, U, have been synthesized and studied by IR spectroscopy [structural family of NaZr₂(PO₄)₃ (NZP)]. Vibrational analysis for the PO₄ tetrahedron and investigation of symmetry relations among trigonal NZP phases showed that ordering of lanthanide atoms in structures of NaZr₂(PO₄)₃ type with space group R c leads to symmetry reduced to P c. The lanthanide atoms occupy the 2b sites. The phosphorus atoms occupy two independent sites: 6f with C ₂ symmetry and 12g with C ₁ symmetry. Factor group analysis admits that the IR spectrum can contain eight v₃ bands and two v₁ bands of the stretching vibrations of the PO₄ ions. The M atoms of actinides occupy statistical positions in the structure, and space group R c is retained.Original Russian Text Copyright © 2004 by V. S. Kurazhkovskaya, D. M. Bykov, and A. I. Orlova__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1013–1019, November–December, 2004.     

The use of thermal lensing for the determination of pyrogens

Based on the optimized spectrophotometric determination of pyrogens (of various classes ( p-aminophenol and endotoxins), thermal lensing was applied to the determination of these substances at the submicrogram level. The limit of detection of p-aminophenol, a pyrogenic impurity in pharmaceutical formulations of paracetamol, by reaction with resorcinol in alkaline solutions is 100 ng mL(-1). Phloroglucinol was considered as an analog of resorcinol as a reagent in this reaction. The conditions of spectrophotometric determination of pyrogenic lipopolysaccharides (endotoxins) by ion-pair formation with methylene blue (the limit of detection is 100 ng mL(-1)), by ion-pair formation with Stains-All (1-ethyl-2-[3-(1-ethylnaphtho[1,2-d]thiazolin-2-ylidene)-2-methylpropenyl]naphtho[1,2-d]thiazolium bromide) (the limit of detection is 500 ng mL(-1)), and by reaction of 2-keto-3-deoxyoctonic acid with thiobarbituric acid (the limit of detection is 800 ng mL(-1)) were proposed. The optimized procedure for 2-keto-3-deoxyoctonic acid was applied for thermal lensing that provided a decrease in the limit of detection to 70 ng mL(-1) and was also used for lipopolysaccharide determination in the endotoxin standard from E. coli.     

Effective account of 2p–2h excitations in molecular calculations by the equation-of-motion method

The excitation energies and oscillator strengths of transitions in the helium atom (as a test system) and carbon dioxide and ethylene molecules are calculated by a modified equation-of-motion method with effective account of the most important polarization effects, including the 2p−2h (two particles-two holes) interactions, in the quasiparticle approximation of the density functional. Two different types of the effective potential of the partile-hole polarization interaction are used. The accuracy of the calculations is sensitive to the type of the potential. It is shown that the account of the polarization corrections for the 2p−2h effects is of fundamental importance since it contributes up to 30% to the values of the excitation energies and oscillator strengths. Odessa Institute of Hydrometeorology. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 4, pp. 615–622, July–August, 1995. Translated by I. Izvekova     

Preparation of [76Br] 5-bromo-2-thiouracil, a positron-emitting melanoma localizing agent

Derivatives of 2-thiouracil are known to incorporate into the growing melanin pigment of melanomas as false melanin precursors. Animal and pilot patient studies have demonstrated, that radioiodinated 5-iodo-2-thiouracil is a promising agent for visualization of melanotic melanomas. In this study, 2-bromo-2-thiouracil was labeled using the positron-emitting isotope ⁷⁶Br (T _1/2 = 16.2 h), which potentially enables to use such advantages of PET as superior spatial resolution and possibility to quantify radioactivity concentration in vivo. The use of Chloramine-T as oxidant provided a labeling efficiency of about 70%.     

Methods for the detection of sulfur mustard metabolites in biological materials: An analytical review

This review surveys published data to generalize methods for the determination of sulfur mustard and its metabolites in various media. Attention is focused on biological materials. Data on the toxicokinetics and metabolism of sulfur mustard are cited, and the problem of choosing a biomarker for the indication of sulfur mustard poisoning is considered.     

Specific properties of hydroxyapatite as a potential transporter of copper ions and its complexes

Russian Chemical Bulletin - Modification of the cocrystallization method for producing hydroxyapatite (HAP) and an HAP-Cu combination to the enzymatic method using alkaline phosphatase leads to a...