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A series of tri-substituted ureas containing an N-methylpiperazine moiety as well as phenyl and N-heterocyclic substituents were synthesized and studied by 1H, 13C NMR and IR spectroscopies. From 1H and 13C NMR data, in CDCl3 solution at room temperature, a fast inter-conversion of the piperazine ring with the N-CH3 group in equatorial position can be proposed. Amino–imino tautomerism is observed for both thiazole and benzothiazole derivatives. Moreover, with the exception of the imino form of the thiazole derivative, the aryl substituted N-carbamoyl group rotates freely. IR data show that the compounds adopt a planar trans conformation of the single bondCOsingle bondNHsingle bond moiety.

Two oximes derived from 3-methyl-3-azabicyclo[3.2.1]octan-8-one (I) and 3-methyl-3-azabicyclo[3.3.1]nonan-9-one (II) were synthesized and studied by IR, 1H and 13C NMR spectroscopy. Compound I adopts in CDCl3 a chair-envelope conformation with the N–CH3 group in equatorial position. Compound II adopts a flattened chair–chair conformation with N–CH3 substituent in equatorial disposition.

The chemical constituents of 34 feline urinary calculi and five urethral plugs were analysed by infrared spectroscopy. The analysis revealed that 18 (52.9 per cent) of the calculi contained magnesium ammonium phosphate hexahydrate (struvite) as the major component; 10 (29.4 per cent) contained complex ammonium urates (three of them also containing calcium phosphate, mainly on the surface); three were composed of calcium phosphates and three were composed mainly of calcium oxalate mono and dihydrates. The urethral plugs were composed primarily of struvite, but also contained large amounts of organic matter. The examination of 16 selected samples by scanning electron microscopy and electron dispersive x-ray analysis revealed that their crystalline structures were similar to those of canine stones.

Presentamos un estudio de la situación de las científicas del área de Ciencia y Tecnologías Físicas en el CSIC, El estudio incluye datos numéricos en cuanto a presencia porcentual de mujeres en las distintas escalas y comisiones de evaluación, así como testimonios personales, reflexiones y consideraciones generales. Se pone de manifiesto el bajo porcentaje de investigadoras en esta Área, Se concluye el estudio con una serie de recomendaciones.

A series of amides derived from syn and anti 2-methyl-2-azabicyclo[2.2.2]octan-5-amines has been synthesized and studied by IR, Raman, 1H and 13C NMR spectroscopy. The crystal structure of 2-methyl-5-syn-(4-quinolinecarboxamide)-2-azabicyclo[2.2.2]octane Id has been determined by X-ray diffraction. It has been found that syn amides present a preferred conformation in CDCl3 solution, with the CH3-N bond in exo position. This is also observed for compound Id in the solid state. However, for anti amides the CH3-N bond adopts a favoured endo position. A conformational analysis using molecular modelling techniques was undertaken in order to gain additional information.

The structural study of several esters derived from syn and anti 5-arylcarbonyloxy-2-methyl-2-azabicyclo[2.2.2]octane hydrochlorides, has been carried out by infrared and Raman spectroscopy. In the case of 2-methyl-5anti-(3-pyridincarbonyloxy)-2-azabicyclo[2.2.2]octane dihydrochloride, the crystal structure has been determined by X-ray diffraction. The spectral differences found between syn and anti epimers and between mono and dihydrochlorides are discussed.

Atomic spectrometry has been used in 20 samples of equine urinary sabulous deposits in order to detect minor elements accompanying the predominant element, calcium, which is present in the form of calcium carbonate (calcite and/or vaterite). The elements measured have been (besides calcium) magnesium, sodium, potassium, iron, copper and manganese. Phosphates, sulphates and silica are frequently present as minor constituents of equine urinary sabulous deposits and uroliths, but their detection can be difficult by infrared (IR) spectroscopy in the original samples due to overlapping with the bands of calcium carbonate. For that reason, the calcination residues of six urinary calculi and 33 samples of sabulous material have been studied by IR spectroscopy and energy dispersive X-ray (EDX) analysis. The results confirm the presence of the above mentioned minor constituents in most samples studied.

The secondary constituents accompanying calcite and vaterite (crystalline forms of calcium carbonate) in the sabulous deposits from 140 vesical samples and one renal sample of equine urine were studied by infrared spectroscopy (IR), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Apatitic calcium phosphate, present in 12 per cent of the samples, generally appeared in the form of spherulites with smooth and rough surfaces. Calcium sulphate, clearly detected by IR in 12·7 per cent of the samples, did not have a characteristic structure under SEM. although EDX detected sulphur in the samples. Amorphous silica was observed in one case and had a nodular appearance. Organic fibres were not as common as might have been expected in equine urinary deposits.

A series of 3,7-dimethyl-9-[(N-substituted)-4-chlorobenzamido]-3,7-diazabicyclo[3.3.1]nonane-9-carboxamides1–3 have been synthesized and studied by infrared, Raman, H and C NMR spectroscopy and molecular modeling techniques. The crystal structure of 3,7-dimethyl-9-[(N-benzyl)-4-chlorobenzamido]-3,7-diazabicyclo[3.3.1]nonane-9-carboxamide (2) was determined by X-ray diffraction. In CDCl and CDOD solutions, these compounds adopt a non-distorted chair-chair conformation with the N-substituents in an equatorial position. Compound 2 prevented acetic acid induced writhing in mice. © 1995, All rights reserved.

The composition and structure of 15 equine uroliths were studied by infrared spectroscopy (IR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and atomic absorption spectrophotometry. Results revealed that the main constituent was calcium carbonate, in its crystalline form of calcite. Other components found in smaller proportions were calcium phosphates, calcium oxalates and, in minor quantities, calcium sulphates. Silica, as well as vaterite, were occasionally identified. SEM examination showed the characteristic morphology of the compounds. Element analysis of calcite crystals detected, besides calcium, significant and varying proportions of magnesium and potassium. The results revealed that calcite and vaterite were present mainly in a "substituted form" in the uroliths studied. © 1995 by William E. Jones. All rights reserved.

A series of amides derived from 3,7-dimethyl-3,7-diazabicyclo[3.3.1]nonan-9-amine (I) have been synthesized and examined by IR, 1H and 13C NMR spectroscopy, and the crystal structure of 9-(3-indolycarboxamido)-3,7-dimethyl-3,7-diazabicyclo[3.3.1]nonane hydrochloride (IV·HCl) has been determined by X-ray diffraction. The 1H and 13CNMR data of the parent amine (I) are also included. These compounds adopt an almost perfect chair-chair conformation with the NCH3 groups in the equatorial position.

In an attempt to synthesize the 3,7-dimethyl-3,7-diazabicyclo[3.3.1]nonan-9-one oxime hydrochloride, the corresponding tautomer imine N-oxide hydrochloride (I·HCl) was obtained, as deduced from X-ray and IR data. By neutralization of I·HCl, the corresponding oxime (II) was obtained and characterized by IR data. From the 1H and 13C NMR spectra of I·HCl and II, a twin-chair conformation for the bicyclic system, more flattened in II, was deduced. This conformation has also been shown by X-ray data for I·HCl. © 1994.

The methyl 2,6-diphenyl-1-methyl-4-oxopiperidine-3,5-dicarboxylates 1 were synthesized by the Mannich procedure from methyl 3-oxoglutarate, benzaldehyde and methylamine. Keto-enol tautomerism as well as configurational isomerism at C-2 were observed. The stereochemistry of the Ib and Ic enolic forms were determined by H and C nmr data. Copyright © 2013 HeteroCorporation.

The vibrational (IR and Raman) and H and C NMR spectra of the analgesic and anti‐inflammatory benzidamine salicylate (Benzasal) have been examined, and the results are described. The crystal structure of this compound has been determined by X‐ray diffraction. To assist in interpretation of the spectroscopic data, some measurements of benzidamine, benzidamine hydrochloride, and salicylic acid have also been made. The most important intermolecular interactions of benzidamine salicylate in the solid state are NH…C hydrogen bonds involving both salicylate oxygen atoms (d = 2.658 Å and 3.228 Å). At least the stronger hydrogen bond remains in CDCl solution. Moreover, the strong intramolecular hydrogen bond O‐H……C within the salicylate anion has also been observed in the solid state and in solution.

The chemical constituents of 171 specimens of canine urinary calculi have been analysed by infrared spectroscopy. The analysis revealed that 46 per cent of the total contained struvite as the major component; 26 per cent contained cystine; 16 per cent were found to be composed of whewellite and, or, weddellite; 8 per cent of urates; 3 per cent of calcium phosphate (apatite and, or, brushite) and 1 per cent of silica. A series of selected samples was also studied by scanning electron microscopy and energy dispersive X-ray analysis (EDAX). This examination revealed structures similar to human stones. Potassium and complex urates containing two or more cations were commonly found in many areas of ammonium orate and sodium urate calculi. Moreover, EDAx analysis detected a calcium enriched urate in several zones of urate calculi. © 1990.