Synthesis of new organophosphorus‐substituted mono‐ and bis(trimethylsilyl)amines with PCH2N fragments and their derivatives

Convenient procedures for the synthesis of new organophosphorus‐substituted mono‐ and bis(trimethylsilyl)amines with PCH₂N moiety are proposed, starting from trimethylsilyl esters of organophosphorus acids, as well as 1,3,5‐trialkylhexahydro‐1,3,5‐triazines and N‐alkoxymethyl bis(trimethylsilyl)amines as aminomethylating reagents. Certain properties of the resulting compounds are presented. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:71–77, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20580     

Synthesis of functionalized 1‐trimethylsiloxy‐substituted O‐trimethylsilyl alkylphosphonites and their derivatives

Nucleophilic addition of trimethylsilyl esters of tricoordinate organophosphorus acids to various functionalized aldehydes with vinyl, aryl, and heterocyclic fragments is proposed as a convenient method for the synthesis of new 1‐trimethylsiloxysubstituted alkylphosphonites and their derivatives at mild conditions. Also the new functionalized derivatives of these phosphonites, including amino groups as well as certain properties of these compounds as important precursors of new functionalized 1‐hydroxyalkylorganophosphorus acids, are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:352–359, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20430     

Synthesis and reactivity of substituted alkoxymethylphosphonites and their derivatives

Alkoxy‐substituted methylphosphonites and their derivatives are prepared using an organomagnesium method of synthesizing the organophosphorus compounds and alkoxymethylation of various PH acids and their derivatives. Also, certain properties of these promising compounds as important precursors of new functionalized organophosphorue compounds with alkoxymethyl fragments are presented. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:281–289, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21015     

Synthesis and functionalization of organophosphorus‐substituted amines with PCH2NH fragments

The convenient procedures for the synthesis of new organophosphorus‐substituted amines with the PCH₂NH moiety are proposed, starting from the derivatives of organophosphorus PH‐acids, as well as 1,3,5‐trisubstituted hexahydro‐1,3,5‐triazines as aminomethylating reagents. Various reactions of functionalization (such as acylation, carboxyethylation, pyridylethylation, and aminoethylation) of the obtained organophosphorus‐substituted amines are presented. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:236–241, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20602     

Synthesis and reactivity of substituted α‐carbonylphosphonites and their derivatives

Convenient methods for the synthesis of functionalized organophosphorus compounds containing carbonyl groups as well as di‐ or trialkoxymethyl fragments attached to phosphorus, and their derivatives, starting from the available derivatives of trivalent phosphorus acids, are proposed, and some properties of the new functionalized organophosphorus compounds are presented. So, the alkylation and acylation reaction of (dialkoxymethyl) phosphonites and their analogs have been studied. It is found that the Arbuzov rearrangement of these compounds was accompanied by the phosphorus–carbon bond cleavage with unique retention of the three‐coordinate phosphorus. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:352–372, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21024     

Synthesis of Organophosphorus‐Substituted Amides of Carbonic Acids with PCHNC(O) and 2,6‐Di‐tert‐butyl‐4‐methylphenol Fragments

Convenient procedures for the synthesis of new organophosphorus‐substituted amides of various carbonic acids with PCHNC(O) and 2,6‐di‐tert‐butyl‐4‐methylphenol (ionol) fragments, starting from the adducts of imines and acyl chlorides, are proposed. Some properties of the new synthesized organophosphorus amides are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:733–737, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20502     

Synthesis and biological activity of phosphorylated compounds of 2‐substituted benzazoles

A series of organophosphorus derivatives have been synthesized by the reaction of phosphorylchloride with 2‐(2′‐hydroxyphenyl)benzimidazole and 2‐(2′‐hydroxynaphthyl)benzimidazole in the presence of KHCO₃ in dry THF in different molar ratios. Newly synthesized derivatives were tested for their insecticidal activity against Periplenata americana. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:246–249, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20533     

Synthesis of new organophosphorus‐substituted derivatives of ethanesulfonic acid

Nucleophilic addition of trimethylsilyl esters of hypophosphorus acid to trimethylsilyl ester and diethylamide of vinylsulfonic acid is proposed as convenient methods for the synthesis of new 2‐sulfonylethylphosphonites and their derivatives under mild conditions. Also the new functionalized derivatives of these phosphonites, including aminomethyl fragments as well as certain properties of these compounds as important precursors of new organophosphorus‐substituted derivatives of ethanesulfonic acid, are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:470–473, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20448     

Synthesis of new organophosphorus compounds using the atherton–todd reaction as a versatile tool

This article discusses the behavior of seven organophosphorus compounds under Atherton–Todd conditions. Therefore, the reactivity and selectivity of different (phen)oxaphosphinines, dioxaphosphinines, dioxaphosphinanes, and diphenylphosphine oxide with three nucleophiles were systematically studied. The results prove the versatility of the Atherton–Todd reaction to a broad range of organophosphorus compounds with different phosphorus environments and reactive P H bonds. The nucleophiles studied in this article were chosen as model substrates for amines and alcohols. Because organophosphorus molecules are important and versatile compounds, for a broad field of applications, novel synthetic approaches are of interest to both academia and industry. As an example, the single‐step synthesis of the bridged 1,3‐phenylene bis(diphenylphosphinate) with potential flame‐retardant properties was added to this study. In addition, the reaction is utilized for the synthesis of a novel organophosphorus anhydride. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:216–222, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21006     

Quantum topological molecular descriptors in QSAR analysis of organophosphorus compounds

A Quantitative structure–activity relationship study is performed on a set of organophosphorus compounds to reveal structural and quantum‐chemical features influencing the toxic effect. The properties derived from the topological analysis of the electron density have been used to model the toxicity data. A multiple linear regression analysis in conjunction with genetic algorithm is used in the study, followed by subsequent validation of the results. Obtained QSAR models are beneficial for virtual screening of toxicity for new compounds of interest. Because toxicity of organophosphorus compounds is dependent on conformational properties, a conformational search has been performed before optimization of geometries. All quantum‐chemical calculations are carried out at DFT/B3LYP level of theory with 6‐311++G(d,p) basis set. Frequency calculations are performed after full geometry optimization. Ab initio wave functions were obtained for further analysis and evaluation of quantum topological properties of target molecules. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012     

Aminophosphines: their chemistry and role as ligands and synthons

In recent years, research in organophosphorus chemistry has mainly focused in designing newer and better phosphorus ligands for synthesizing novel metal complexes with improved catalytic activities. Aminophosphines [tricoordinate phosphorus(III)–nitrogen systems] are considered as versatile compounds owing to the presence of nitrogen centres which, in principle, can influence additional reactivity features. They are quite sensitive to air and moisture due to the presence of polar P? N bond(s). In spite of this, research in aminophosphine chemistry is gaining momentum day‐by‐day and this is due mainly to one reason: their rich behaviour as ligands in metal complex chemistry and subsequently in catalysis. Their role as synthons in inorganic heterocyclic chemistry has also helped produce new types of heterocycles. In this paper, the chemistry of simple acyclic aminophosphines (synthesis, characterization, reactivity and applications) is covered and particular focus is given to their ability to form chalcogenides along with their role played as ligands in coordination chemistry and as synthons in inorganic heterocyclic chemistry. Copyright © 2009 John Wiley & Sons, Ltd.     

Synthesis,structure, and antifungal activity of dihydropyridones containing boronate esters

We have prepared a series of novel 2,3‐dihydro‐4‐pyridones containing boronate esters using the aza Diels–Alder reaction with Danishefsky's diene and imines derived from formylphenylboronic acids. This reaction can be carried out in moderate to high yields using Yb(OTf)₃ as a Lewis acid catalyst. Two new boron compounds exhibited moderate antifungal activity (at 100 μg disk⁻¹) using Amphotericin B as a control. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:56–63, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20512     

Structural determination of two new triterpenoids biotransformed from glycyrrhetinic acid by Mucor polymorphosporus

Five hydroxylated derivatives of glycyrrhetinic acid by Mucor polymorphosporus were isolated. Among them, 6β, 7β‐dihydroxyglycyrrhentic acid (2) and 27‐hydroxyglycyrrhentic acid (3) are new compounds. Their chemical structures were identified by spectral methods including 2D‐NMR. Copyright © 2009 John Wiley & Sons, Ltd.     

Study of reaction between activated acetylenes and N,N′‐diethyl‐2‐thiobarbituric acid in the presence of isocyanides or triphenylphosphine

In a series of separate experiments reaction between N,N′‐diethyl‐2‐thiobarbituric acid and acetylenic diesters in the presence of isocyanides or triphenylphosphine led to highly functionalized 4H‐pyrano[2,3‐d]thiopyrimidine or 1,4‐di‐ionic organophosphorus derivatives. The ¹H NMR spectra of diethyl‐7‐(2,6‐dimethylphenylamino)‐4‐oxo‐2‐thio‐ 1,3‐diethyl‐4H‐pyrano[2,3‐d]pyrimidine‐5,6‐dicarboxylate showed dynamic NMR effect that was attributed to restricted rotation around the aryl‐nitrogen single bond. Activation free energy (ΔG^≠) for this process is about 54.85 ± 2 kJ mol⁻¹. Betaines as 1,4‐diionic organophosphorus compounds in this reaction are possessed of two vicinal stereogenic centers and exist in the solution as a mixture of two diastereoisomers. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:228–235, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20601     

Emerging drugs: mechanism of action,mass spectrometry and doping control analysis

The number of compounds and doping methods in sports is in a state of constant flux. In addition to ‘traditional’ doping agents, such as anabolic androgenic steroids or erythropoietin, new therapeutics and emerging drugs have considerable potential for misuse in elite sport. Such compounds are commonly based on new chemical structures, and the mechanisms underlying their modes of action represent new therapeutic approaches arising from recent advances in medical research; therefore, sports drug testing procedures need to be continuously modified and complementary methods developed, preferably based on mass spectrometry, to enable comprehensive doping controls. This tutorial not only discusses emerging drugs that can be categorized as anabolic agents (selective androgen receptor modulators, SARMs), gene doping [hypoxia‐inducible factor stabilizers, peroxisome‐proliferator‐activated receptor (PPAR)δ‐agonists] and erythropoietin‐mimetics (Hematide) but also compounds with potentially performance‐enhancing properties that are not classified in the current list of the World Anti‐Doping Agency. Compounds such as ryanodine‐calstabin‐complex modulators (benzothiazepines) are included, their mass spectrometric properties discussed, and current approaches in sports drug testing outlined. Copyright © 2009 John Wiley & Sons, Ltd.     

Structure elucidation and NMR assignments of two new pyrrolidinyl quinoline alkaloids from chestnut honey

The complete ¹H, ¹³C and ¹⁵N NMR spectral assignments of two new alkaloids isolated from chestnut honey and structurally related to kynurenic acid have been made using 1‐D and 2‐D NMR techniques, including COSY, HMQC and HMBC experiments. The new compounds have been identified as 3‐(2′‐pyrrolidinyl)‐kynurenic acid and its γ‐lactam derivative. Copyright © 2009 John Wiley & Sons, Ltd.     

Indium trichloride–catalyzed synthesis of some novel 2,2′‐(N,N′‐diarylamino)‐ 4,4′‐diaryl‐5,5′‐arylidenebisthiazoles and their insecticidal activity

A series of novel 2,2′‐(N,N′‐diarylamino)‐4,4′‐diaryl‐5,5′‐arylidene‐bisthiazoles 2 were rapidly and smoothly prepared in good yields by using non conventional techniques i.e. microwave or ultrasonic irradiation, through indium trichloride catalyzed electrophilic substitution reaction of 2‐(N‐arylamino)‐4‐arylthiazoles 1 with various arylaldehydes. All the synthesized compounds were characterized on the basis of their elemental analyses and spectral data (IR, PMR and Mass). The synthesized compounds were also evaluated for their insecticidal activity against Helicoverpa armigera and gave promising results. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:224–231, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20537     

Microwave‐assisted synthesis of some 2,4‐thiazolidinedione derivatives

The condensation of 5‐[4′‐(2″‐halo‐ethoxy)benzylidenyl]‐2,4‐thiazolidinediones 2 when separately carried with different 2‐amino thiazoles 3 and different sulphanilamides 4 in DMF, using potassium hydroxide in the presence of a catalytic amount of a phase transfer catalyst, gave new 5‐[4′‐(4″‐aryl‐thiazol‐2″‐yl‐aminoethoxy)‐3′/5′‐substituted benzylidenyl]‐2,4‐thiazolidinediones 5 and 5‐[4′‐(2″/4″‐sulphonamidophenyl aminoethoxy)‐3′/5′‐substituted benzylidenyl]‐2,4‐thiazolidinediones 6 derivatives in good yields, respectively. The structures of all new compounds were established from analytical and spectral data. All the reaction sequences were carried under microwave irradiation, as an efficient tool. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:151–156, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20528     

Synthesis and characterization of new O,O‐diethyl phosphorothioates derived from substituted tetrazolo[1,5‐a]quinolin‐ 4‐ylmethanol derivatives

A simple and convenient method is developed for the synthesis of new O,O‐diethyl O‐(substituted tetrazolo[1,5‐a]quinolin‐4‐yl)methyl phosphorothioates, which has been synthesized for the first time from tetrazolo[1,5‐a] quinolines via tetrazolo[1,5‐a]quinolin‐4‐ylmethanol derivatives. The structures of the all newly synthesized compounds were elucidated by analytical and spectral methods. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 20:436–441, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20570     

C3‐symmetric trialkyl phosphites as starting compounds of asymmetric synthesis

Chiral C₃‐symmetric trialkyl phosphites, derivatives, of (−)‐(1R,2S,5R)‐menthol, and (−)‐di‐O‐isopropylidene‐1,2:5,6‐α‐D ‐glucofuranose, have been studied as starting reagents for the preparation of chiral organophosphorus compounds. The reactions involve induction at the α‐carbon atom of substituted α‐alkylphosphonates. The stereoselectivity of the reaction depends on the structure of the starting compounds and the reaction conditions. The configurations of the alkylphosphonates were defined by means of NMR spectroscopy and by transformation into corresponding alkylphosphonic acids. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:138–143, 2000