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), for bone targeting, for the design of supramolecular or hybrid materials, for the functionalization of surfaces, for analytical purposes, for medical imaging or as phosphoantigen. These applications are covering a large panel of research fields including chemistry, biology and physics thus making the synthesis of phosphonic acids a determinant question for numerous research projects. This review gives, first, an overview of the different fields of application of phosphonic acids that are illustrated with studies mainly selected over the last 20 years. Further, this review reports the different methods that can be used for the synthesis of phosphonic acids from dialkyl or diaryl phosphonate, from dichlorophosphine or dichlorophosphine oxide, from phosphonodiamide, or by oxidation of phosphinic acid. Direct methods that make use of phosphorous acid (H3PO3) and that produce a phosphonic acid functional group simultaneously to the formation of the P–C bond, are also surveyed. Among all these methods, the dealkylation of dialkyl phosphonates under either acidic conditions (HCl) or using the McKenna procedure (a two-step reaction that makes use of bromotrimethylsilane followed by methanolysis) constitute the best methods to prepare phosphonic acids.

SK3 channels are abnormaly expressed in metastatic cells, and Ohmline (OHM), an ether lipid, has been shown to reduce the activity of SK3 channels and the migration capacity of cancer cells. OHM incorporation into the plasma membrane is proposed to dissociate the protein complex formed between SK3 and Orai1, a potassium and a calcium channel, respectively, and would lead to a modification in the lipid environment of both the proteins. Here, we report the synthesis of deuterated OHM that affords the determination, through solid-state NMR, of its entire partitioning into membranes mimicking the SK3 environment. Use of deuterated lipids affords the demonstration of an OHM-induced membrane disordering, which is dose-dependent and increases with increasing amounts of cholesterol (CHOL). Molecular dynamics simulations comfort the disordering action and show that OHM interacts with the carbonyl and phosphate groups of stearoylphosphatidylcholine and sphingomyelin and to a minor extent with CHOL. OHM is thus proposed to remove the CHOL OH moieties away from their main binding sites, forcing a new rearrangement with other lipid groups. Such an interaction takes its origin at the lipid–water interface, but it propagates toward the entire lipid molecules and leads to a cooperative destabilization of the lipid acyl chains, that is, membrane disordering. The consequences of this reorganization of the lipid phases are discussed in the context of the OHM-induced inhibition of SK3 channels.

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Very few hybrid organic-inorganic framework (HOIF) exhibit direct coupling between spins and dipoles and are also restricted to a particular COOH-based system. It is shown how one can design a hybrid system to obtain such coupling based on the rational design of the organic ligands. The layered phosphonate, MnO 3 PC 6 H 5 ⋅H 2 O, consisting of perovskite layers stacked with organic phenyl layers, is used as a starting potential candidate. To introduce dipole moment, a closely related metal phosphonate, MnO 3 PC 6 H 4 -m-Br⋅H 2 O is designed. For this purpose, this phosphonate is prepared from 3-bromophenylphosphonic acid that features one electronegative bromine atom directly attached on the aromatic ring in the meta position, lowering the symmetry of precursor itself. Thus, bromobenzene moieties in MnO 3 PC 6 H 4 -m-Br⋅H 2 O induce a finite dipole moment. This new designedcompound exhibits complex magnetism, as observed in layered alkyl chains MnO 3 PC n H 2n+1 ⋅H 2 O materials, namely, 2D magnetic ordering ≈20 K followed by weak ferromagnetic ordering below 12 K (T 1 ) with a magnetic field (H)-induced transition ≈25 kOe below T 1 . All these magnetic features are exactly captured in the T and H-dependent dielectric constant, ε′(T) and ε′(H). This demonstrates direct magnetodielectric coupling in this designed hybrid and yields a new path to tune multiferroic ordering and magnetodielectric coupling.

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Novel polyheterocycles were prepared from a new annellation reaction which proceeds by nucleophilic substitution followed by an intramolecular Horner‐Wadsworth‐Emmons reaction between imides and β‐functionalized phosphonates.

Natural O-alkyl-glycerolipids, also known as alkyl-ether-lipids (AEL), feature a long fatty alkyl chain linked to the glycerol unit by an ether bond. AEL are ubiquitously found in different tissues but, are abundant in shark liver oil, breast milk, red blood cells, blood plasma, and bone marrow. Only a few AEL are commercially available, while many others with saturated or mono-unsaturated alkyl chains of variable length are not available. These compounds are, however, necessary as standards for analytical methods. Here, we investigated different reported procedures and we adapted some of them to prepare a series of 1-O-alkyl-glycerols featuring mainly saturated alkyl chains of various lengths (14:0, 16:0, 17:0, 19:0, 20:0, 22:0) and two monounsaturated chains (16:1, 18:1). All of these standards were fully characterized by NMR and GC-MS. Finally, we used these standards to identify the AEL subtypes in shark and chimera liver oils. The distribution of the identified AEL were: 14:0 (20–24%), 16:0 (42–54%) and 18:1 (6–16%) and, to a lesser extent, (0.2–2%) for each of the following: 16:1, 17:0, 18:0, and 20:0. These standards open the possibilities to identify AEL subtypes in tumours and compare their composition to those of non-tumour tissues.