The phosphonic acid functional group, which is characterized by a phosphorus atom bonded to three oxygen atoms (two hydroxy groups and one P=O double bond) and one carbon atom, is employed for many applications due to its structural analogy with the phosphate moiety or to its coordination or supramolecular properties. Phosphonic acids were used for their bioactive properties (drug, pro-drug), f...

Z. Naturforsch. 50b, 855-858 (1995); received November 11, 1994 Organophosphonic Acid Anhydrides, Phosphonic Acid Anhydrides, Stereochemistry, NMR Spectra The phosphonic acid anhydrides of the general formula [R P 0 2]„ have been prepared with R = Me, Et, z-Pr, r-Bu, and Ph from the corresponding phosphonic acids and their chlorides and esters. Mass spectrometric data indicate that the trimers ...

DNA sequence analysis of the modABCD operon of Escherichia coli revealed the presence of four open reading frames. The first gene, modA, codes for a 257-amino-acid periplasmic binding protein enunciated by the presence of a signal peptide-like sequence. The second gene (modB) encodes a 229-amino-acid protein with a potential membrane location, while the 352-amino-acid ModC protein (modC product...

In this study, perfluorinated phosphonic acid modifications were utilized to modify zinc oxide (ZnO) nanoparticles because they create a more stable surface due to the electronegativity of the perfluoro head group. Specifically, 12-pentafluorophenoxydodecylphosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, and (1H,1H,2H,2H-perfluorododecyl)phosphonic acid have been used to form thin f...

The activation of silent natural product gene clusters is a synthetic biology problem of great interest. As the rate at which gene clusters are identified outpaces the discovery rate of new molecules, this unknown chemical space is rapidly growing, as too are the rewards for developing technologies to exploit it. One class of natural products that has been underrepresented is phosphonic acids, ...

The modABC gene products constitute the molybdate-specific transport system in Escherichia coli. Another operon coding for two proteins which diverges from the modABCD operon has been identified. The first gene of this operon codes for a 262-amino-acid protein, designated ModE (28 kDa), and the second genes codes for a 490-amino-acid protein. ModF (54 kDa). The role of ModF has not yet been det...

The Natural Product Discovery Institute contains a set of more than 30 000 fungal and actinomycete organisms that can be used for natural product discovery. The natural product library contains purified compounds, partially purified column fractions, and crude extracts from natural product-producing organisms. The collection is available for screening. This site describes a roadmap for analysin...

Rare earth ion-doped yttrium oxide (Y2O3) nanocrystals are nontoxic and can be prepared as upconversion materials for cellular imaging, but they do not suspend well in water. In contrast to their tendency to dissolve in acidic media, yttria (Y2O3) nanoparticles readily react with phosphonic acids to give phosphonate-bonded yttria particles. Through the choice of phosphonic acid, the hydrophilic...

High-resolution solid state 13C, 23Na and 31P NM R data have been obtained for the acid form and for several salts o f the phosphonic acids: ethane-1 ,2 -diphosphonic acid, ethane-l-hydroxy1.1-diphosphonic acid (H E D P ), and 3-am ino-l-hydroxypropane-l,l-diphosphonic acid. The data provide evidence by which sample purity and crystallinity may be examined and from which the size of the asymmet...