Abstract:Background:

Abstract:Growing interest in the biological activity of aminobisphosphonates has stimulated the development of methods for their synthesis. Although several general procedures were previously elaborated to reach this goal, aminobisphosphonate chemistry is still developing quite substantially. Thus, innovative modifications of the existing commonly used reactions, as well as development of new procedures, are presented in this review, concentrating on recent achievements. Additionally, selected examples of aminobisphosphonate derivatization illustrate their usefulness for obtaining new diagnostic and therapeutic agents.

The sensing characteristics of a Bragg grating imprinted in a specially developed highly birefringent side-hole fiber were investigated in detail. We showed that such a grating has almost identical sensitivities to temperature for both linearly polarized modes LP01(x) and LP01(y) (approximately 5.9 pm/K) and significantly different sensitivities to hydrostatic pressure (-1.93 pm/MPa for LP01(x) and +5.37 pm/MPa for LP01(y) mode). The sensitivity differences versus mode polarization are so high that this effect can be employed for simultaneous sensing of temperature and pressure by interrogation of the wavelength shifts at LP01(x) and LP01(y) modes. Applying interferometric methods, we also measured the sensitivity of the host side-hole fiber to temperature and hydrostatic pressure for each polarization mode. Our results show that there is good agreement between the normalized sensitivities of the host side-hole fiber and those of the grating for the same polarization modes.

A method for measuring the sensitivity of Bragg gratings to external parameters for different spatial and polarization modes is presented together with the results of measurements of sensitivity to temperature and elongation for LPx01, LPy01, LPx11 and LPy11 modes. The difference in response according to the type of mode shows the possibility of performing simultaneous temperature and elongation measurements using two-mode Bragg gratings.

We present a statistical analysis of 66 days of observations of quiescent (non-erupting) coronal cavities and associated velocity and thermal structures. We find that nested rings of LOS-oriented velocity are common in occurrence and spatially well correlated with cavities observed in emission. We find that the majority of cavities possess multiple rings, and a range in velocity on the order of several km/sec. We find that the tops of prominences lie systematically below the cavity center and location of largest Doppler velocity. Finally, we use DEM analysis to consider the temperature structure of two cavities in relation to cavity, prominence, and flows. These observations yield new constraints on the magnetic structure of cavities, and on the conditions leading up to solar eruptions.

The reaction of diethyl phosphite with triethyl orthoformate and a primary amine followed by hydrolysis is presented, and the reaction was suitable for the preparation of (aminomethylene)bisphosphonates. 3-Amino-1,2,4-triazole was chosen as an interesting substrate for this reaction because it possesses multiple groups that can serve as the amino component in the reaction—namely, the side-chain and triazole amines. This substrate readily forms 1,2,4-triazolyl-3-yl-aminomethylenebisphosphonic acid (compound 1) as a major product, along with N-ethylated bisphosphonates as side products. The in vitro antiproliferative effects of the synthesized aminomethylenebisphosphonic acids against J774E macrophages were determined. These compounds exhibit similar activity to zoledronic acid and higher activity than incadronic acid.

SummaryA convenient approach has been developed to α-aminoalkylidenebisphosphonates and their asymmetric phosphonyl-phosphinyl and phosphonyl-phosphinoyl analogues by α-phosphonylation, α-phosphinylation or α-phosphinoylation of 1-(N-acylamino)alkylphosphonates, that, in turn, are easily accessible from N-acyl-α-amino acids. Effective electrophilic activation of the α-position of 1-(N-acetylamino)alkylphosphonates was achieved by electrochemical α-methoxylation of these compounds in methanol, mediated with NaCl, followed by displacement of the methoxy group with triphenylphosphonium tetrafluoroborate to give hitherto unknown 1-(N-acetylamino)-1-triphenylphosphoniumalkylphosphonate tetrafluoroborates. The latter compounds react smoothly with trialkyl phosphites, dialkyl phosphonites or alkyl phosphinites in the presence of Hünig’s base and methyltriphenylphosphonium iodide in a Michaelis–Arbuzov-like reaction to give the expected alkylidenebisphosphonates, 1-phosphinylalkylphosphonates or 1-phosphinoylalkylphosphonates, respectively, in good yields.

The aim of the study was to determine the impact of steroidal medications on the structure and mechanical properties of supporting tissues of sheep under experimentally-induced osteoporosis. A total of 21 sheep were used, divided into three groups: a negative control (KN) (n = 3), a positive control (KP) (n = 3) with ovariectomy, and a steroidal group (KS) (n = 15) with ovariectomy and glucocorticosteroids. All animals were kept on a low protein and mineral diet and had limited physical activity and access to sunlight. Quantitative computed tomography was the examination method. The declines in the examined parameter values in the KS group were more than three times higher than in the KN group. The study suggests that a glucocorticosteroidal therapy accelerates and intensifies processes taking place in the course of osteoporosis. The combination of glucocorticosteroids with ovariectomy, a restrictive diet, limited physical activity, and no access to sunlight leads to a decrease in radiological bone density.