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New derivatives of phosphoramido acid with the formula(C6H11NCH3)(NHCOCF3)P(O)(O−)(CH3–+NH2–C6H11)(1) (amidophosphoricacid), (C6H5)2P(O)(O−)(+NH3–C6H4–NH2)(2) (phosphonicacid), (C6H5O)2P(O)(O−)(+NH3–C6H4–NH2) (3) (phosphoricacidester) were synthesized and characterized by X-ray crystallography. The asymmetric unit of compounds 1–3consists of one molecule with the P atom in a tetrahedral environment. The X-ray structural analysis showed that the H-bond patterns depend on the kind of atoms linked to the P atom. In the crystal packing of compound 1, P(O)···H–N and C(O)···H–N hydrogen bonds in 3and P(O)···H–N distances in compounds 2 and 3 led to a one-dimensional arrangement. The energy of P–O···H–N hydrogen bond (EHB) model and stabilizing energies (E2) were calculated. Hirshfeld surface analysis demonstrated that the C···H contact is attributed to CH···πcontact in the 2 and 3 compounds and the F···H contact is referred to hydrogen bond in one O···H counterion interaction. Quantitative structure–activity relationship (QSAR) was used to comprehend the relationship between molecular structural features and the inhibitory of investigated compounds. The use of density functional theory along with the QSAR model for enzymes revealed the importance of QHparameter in describing the anti-AChE and anti-urease activities of monophosphoramidates including P(O)–NH2moiety.

Five new bisphosphoramide-based LnIIInitrate complexes [La2(NO3)6L3I]n(1), [Ce2(NO3)6L3I]n(2), [Sm2(NO3)6L3II]n(3), Sm2(NO3)6L3III(4), and Er(NO3)3L2III(5) [LI= piperazine-1,4-diylbis(diphenyl phosphine oxide), LII= N,N′-(ethane-1,2-diyl)bis(N-methyl-P,P-diphenylphosphinic amide, and LIII= N,N′-(ethane-1,2-diyl)bis(P,P-diphenylphosphinic amide)] have been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), and single crystal X-ray and powder diffractions. The results of the X-ray diffraction analysis revealed the new polymorph of LIII, and the structural diversity of the synthesized complexes in the solid state. Complexes 1–3display two-dimensional coordination polymers (2D-CP), containing layers with honeycomb (6, 3) topology. In these 2D-CPs, each Ln center (La, Ce, and Sm in 1, 2, and 3, respectively) could be considered as a triconnected node, linked by three bridging bisphosphoramide ligands as two-connecting linkers. In contrast, 4is a discrete binuclear complex, in which bidentate LIIIligand has two entirely different conformations: the syn chelating and the anti bridging. Cationic complex 5shows the monomeric structure, where bidentate LIIIadopts the syn-chelating conformation. A comprehensive luminescence investigation has been performed on free ligands and their corresponding complexes as well. The synthesized compounds display a variety of luminescence behavior, including the ligand-centered fluorescence in 1, 2, and 5, two distinct emission peaks in 1and 2, characteristic Sm-centered f–f emission in 3and 4, and excitation-dependent emission in LIII, 1, and 2. Furthermore, the time-dependent density functional theory (TD-DFT) study was carried out on the reported compounds to understand the nature of the emission peaks and the observed luminescence properties. The solid-state emission quantum yields of lanthanide complexes were also determined at different excitation wavelengths.

A series of temephos (Tem) derivatives with the general structure of P(O)NH–X–NHP(O) (1–22) were synthesized and characterized by 31P, 13C, 1H NMR and FT-IR spectral techniques. The electron density (ρ) value at the bond critical point (bcp) of P(1′)–O(1′)···(1)H–N(1) (0.040 e Å−3) P(1)–O(1)···(1′)H–N(1′) (0.031 e Å−3) as well as the stabilization energy of electronic delocalization of results of NBO analysis showed the hydrogen bonding energy in P(1′)–O(1′)···(1)H–N(1) model (E2= −72.15 kJ mol−1) and P(1)–O(1)···(1′)H–N(1′) (E2= −45.67 kJ mol−1) of the crystal cluster 7. The activities of Tem derivatives were evaluated using the modified Ellman’s method on cholinesterase (ChE) enzymes. The insecticide activity of Tem analogous appraised for the elm leaf beetle in which the 18had more effective than the other compounds in inhibition α-esterase of insect. Principal component analysis–quantitative structure activity relationship (PCA–QSAR) models indicated that it was deduced that the frontier molecular orbital energy parameters in PC1are predominated from those related to electronic in PC2and structural parameters in PC3equation. Multiple linear regressions–QSAR models clarified that the molecular descriptors like an integrated net charge of nitrogen atom (QN), polarizability (PLN–H) and lowest unoccupied molecular orbital (ELUMO) proved important in defining the activity of the candidates.

In an attempt to introduce a new class of carbon steel corrosion inhibitors, the anti-corrosion properties of two heteroatom-containing phosphoramides; N-(5-methylisoxazol-3-yl)-P,P-diphenylphosphinic amide (MAPP) and diphenyl (5-methylisoxazol-3-yl)phosphoramidate (PMAP) were theoretically investigated. Density functional theory (DFT) calculations were performed using B3LYP functional and 6–31+G(d,p) basis set to evaluate the inhibition efficacy of MAPPand PMAPin the presence of HCl molecule. Based on the frontier molecular orbitals energy gap (Eg), dipole moment, global hardness, electrophilicity, and nucleophilicity values, we concluded that PMAPacts as a strong anti-corrosion. With the aim of identifying the most stable configuration of inhibitor-HCl, the HCl molecule was approached to all probable reactive sites of inhibitors determined by molecular electrostatic potential plots. It was revealed that molecule PMAPforms a stronger hydrogen bond with the HCl molecule and has a higher ΔH(-4.33 kcal.mol−1) than MAPP(ΔH = -3.50 kcal.mol−1). Adsorption behavior of MAPPand PMAPon a Fe (1 1 0) superlattice was studied using molecular dynamics (MD) simulations at T = 298, 308, and 318 K and in the presence of n = 1–4 molecules of MAPPand PMAP. Radial pair distribution function analysis revealed that molecules MAPPand PMAPhave the ability to form a chemical bond with metal, and thus protect it from corrosion. The best anti-corrosion performance occurs at T = 298 K and higher concentrations of inhibitors. The adsorption energy of the PMAPmolecule on the steel surface (-258.8 kcal.mol−1at 298 K and for n = 4) is more negative than that of MAPP(-239.5 kcal.mol−1) at the same conditions, indicating that PMAPcan be used as an effective corrosion inhibitor for carbon steel in acidic media.

New phosphorhydrazide compounds (1–7, 13, 15–16) and thiophosphorhydrazide (14and 17) were synthesized and characterized by 31P, 13C, 1H NMR and IR spectroscopy. Furthermore, the crystal structure of compound (C6H5NH)(C6H5O)P(O)(NH–NH2) (2) was investigated. The activities of derivatives on acetylcholinesterase (AChE) and urease were determined. Quantitative structure–activity relationship (QSAR) was used to understand the relationship between molecular structural features and inhibitory. DFT–QSAR models for enzymes demonstrated the importance of ELUMOparameter in describing the anti-AChE and anti-urease activities of the synthesized compounds. The correlation matrix of QSAR models and docking analysis confirmed that electrophilicity descriptor can control the influence of the polarizability properties of N–H functional group of PAH derivatives in the inhibition of enzymes.

Novel organophosphorus compounds, containing Nicotinamide, with formula C5H4NC(O)NHP(O)R2, R=Cl (1), OH (2), N(C2H5)2(3), N(C3H7)2(4), N(n-C4H9)2(5), NHC3H5(6), NHC5H9(7), were synthesized and characterized by 1H, 13C, 31P, NMR, IR, spectroscopy and elemental analysis. Single crystal structures of 3 7were determined by X-ray crystallography. 1HNMR spectra of compounds 2, 3, 6–8demonstrated interesting long-range coupling constant, nJP,H(n= 5 7). Crystallographic data revealed that in both molecules 3and 7, the phosphoryl and the carbonyl groups have anti-configurations and the phosphorus atoms in these structures have distorted tetrahedral configuration. All the hydrogen bonds and electrostatic interactions make a three dimensional polymeric network for both 3and 7. Interestingly, two independent conformers were detected in the unit cell of compound 7. The two conformers of the title compound can be observed in a solid phase but only one compound defined in a solution. These two conformers are connected to each other by a short contact, N (amine)···H–C (pyridine) with 2.626 Å distance. The molecular geometry of 7was calculated by DFT/B3LYP (6–31+G**) quantum chemical calculations. The computational optimized geometric parameters and vibrational frequencies showed a good agreement with the experimental results, considering reasonable variations arising from the differences between solid and gaseous phases. Theoretical calculations revealed that the more stable conformer of the title compound is conformer 1 with the energy of −1335.723996 a.u., which is about 1.17 kcal/mol lower than the energy of conformer 2.

Five new ammonium phosphinates with formula [XC6H4NHC(O)NHP(O)YO]−[H2Y]+ (Y = N(CH3)(CH2C6H5), X = H (IV), CH3 (V), NO2 (VI); Y = NH(CH2C6H5), X = H (VII), NO2 (VIII)) were synthesised by the reaction of N-arylureidophoshoryl dichlorides with N-methylbenzylamine or benzylamine in the presence of an excess amount of the corresponding amine. All new compounds were characterised by NMR and IR spectral data and elemental analysis. Their antimicrobial activity was tested against some Gram-positive and Gram-negative bacteria and fungi. Compounds IV and VIII exhibited moderate activity in vitro against Bacillus subtilis. In addition, compound VIII moderately inhibited Pseudomonas aeruginosa. The crystal structure of benzylmethylammonium(3-phenylureido)(benzylmethylamino)phosphinate (IV) was also determined. This compound crystallises in the orthorhombic system.

The reaction of 2‐morpholinoethylimino‐bis(methylenephosphonic acid) (H4L) with cobalt(II), nickel(II) acetate, and cadmium(II) chloride in ethanol/water mixed solvents afforded three new crystal‐engineered supramolecular metal phosphonates, Co(H3L)2·2H2O (1), Ni(H3L)2·2H2O (2), and [Cd2Cl4(H2O)6]0.5[H4L] (3) by using a layering technique. The cobalt(II) ions in complex 1are hexacoordinated by four phosphonate oxygen atoms and two imino nitrogen atoms. The mononuclear units of complex 1are connected through hydrogen bonds to form a three dimensional supramolecular network. The structure of compound 2is analogous to that of 1except that the cobalt(II) ion in compound 1is replaced by nickel(II) in compound 2. In the molecular structure of compound 3, cadmium is coordinated to three chloride ions and three aqua oxygen atoms to form a novel neutral dinuclear complex. Several hydrogen bonds connect the dinuclear complex and the neutral form of the ligand to build a supramolecular three dimensional structure.

The differences in the inhibition activity of organophosphorus agents are a manifestation of different molecular properties of the inhibitors involved in the interaction with the active site of enzyme. We were interested in comparing the inhibition potency of four known synthesized carbacylamidophosphates with the general formula RC(O)NHP(O)Cl2, constituting organophosphorus compounds, where R = CCl3(1), CHCl2(2), CH2Cl (3) and CF3(4), and four new ones with the general formula RC(O)NHP(O)(R')2, where R' = morpholine and R = CCl3(5), CHCl2(6), CH2Cl (7), CF3(8), on AChE and BuChE activities. In addition, in vitro activities of all eight compounds on BuChE were determined. Besides, in vivo inhibition potency of compounds 2 and 6, which had the highest inhibition potency among the tested compounds, was studied. The data demonstrated that compound 2 from the compound series 1 to 4 and compound 6 from the compound series 5 to 8 are the most sensitive as AChE and BuChE inhibitors, respectively. Comparing the IC50values of these compounds, it was clear that the inhibition potency of these compounds for AChE are 2- to 100-fold greater than for BuChE inhibition. Comparison of the kinetics (IC50, Ki, kp, KAand KD) of AChE and BuChE inactivation by these compounds resulted in no significant difference for the measured variables except for compounds 2 and 6, which appeared to be more sensitive to AChE and BuChE by significantly higher kpand Kivalues and a lower IC50value in comparison with the other compounds. The LD50value of compounds 2 and 6, after oral administration, and the changes of erythrocyte AChE and plasma BuChE activities in albino mice were studied. The in vivo experiments, similar to the in vitro results, showed that compound 2 is a stronger AChE and BuChE inhibitor than the other synthesized carbacylamidophosphates. Furthermore, in this study, the importance of electropositivity of the phosphorus atom, steric hindrance and leaving group specificity were reinforced as important determinants of inhibition activity

Using phosphorus pentachloride as a substrate, carbacylamidophosphates of the general formula (p‐X‐C6H4) C(O)NHP(O)(R)2; (X=Cl and R=Cl, 2a; X=Br and R=Cl, 3a; X=Me and R=Cl, 4a; X=Cl and R=piperidine, 2b; X=Br and R=piperidine, 3b; X=Me and R=piperidine, 4b; X=H and R=cyclohexylamine, 1c; X=Cl and R=cyclohexylamine, 2c; X=Br and R=cyclohexylamine, 3c; X=Me and R=cyclohexylamine, 4c; X=H and R=p‐Me‐cyclohexylamine, was prepared and characterized by 1H, 31P and 13C NMR and IR spectroscopy and elemental analysis. Different group attached on phosphorus nuclei affect on IR and NMR spectra. Three‐bond coupling constants between phosphorus and carbon nucleus, 3J(P,Caliphatic) in the 1b–4band 1c–4ccontaining piperidine or cyclohexylamine groups, were greather than two‐bond coupling constants, 2J(P,Caliphatic). The structures of 2band 3bwere determined by single‐crystal X‐ray diffraction techniques. The both molecule crystals are composed of a centrosymmetric dimer via N‐H···O bonds. 3bexists as two independent molecules in crystal lattice.

Some new N‐4‐Fluorobenzoyl phosphoric triamides with formula 4‐F‐C6H4C(O)N(H)P(O)X2, X = NH‐C(CH3)3(1), NH‐CH2‐CH=CH2(2), NH‐CH2C6H5(3), N(CH3)(C6H5) (4), NH‐CH(CH3)(C6H5) (5) were synthesized and characterized by 1H, 13C, 31P NMR, IR and Mass spectroscopy and elemental analysis. The structures of compounds 1, 3and 4were investigated by X‐ray crystallography. The P=O and C=O bonds in these compounds are anti. Compounds 1and 3form one dimensional polymeric chain produced by intra‐ and intermolecular ‐P=O···H‐N‐ hydrogen bonds. Compound 4forms only a centrosymmetric dimer in the crystalline lattice via two equal ‐P=O···H‐N‐ hydrogen bonds. 1H and 13C NMR spectra show two series of signals for the two amine groups in compound 1. This is also observed for the two α‐methylbenzylamine groups in 5due to the presence of chiral carbon atom in molecule. 13C NMR spectrum of compound 4shows that 2J(P,Caliphatic) coupling constant for CH2group is greater than for CH3in agreement with our previous study. Mass spectra of compounds 1‐3(containing 4‐F‐C6H4C(O)N(H)P(O) moiety) indicate the fragments of amidophosphoric acid and 4‐F‐C6H4CN+that formed in a pseudo McLafferty rearrangement pathway. Also, the fragments of aliphatic amines have high intensity in mass spectra.

Some new N‐carbonyl, phosphoramidates with formula C6H5C(O)N(H)P(O)R2(R = NC3H6(1), NC6H12(2), NHCH2CH=CH2(3), N(C3H7)2(4)) and CCl3C(O)N(H)P(O)R′2(R′ = NC3H6(5), NHCH2CH=CH2(6)) were synthesized and characterized by 1H, 13C, 31P NMR and IR spectroscopy and elemental analysis. The structures were determined for compounds 1and 2. Compound 1exists as two crystallographically independent molecules in crystal lattice. Both compounds 1and 2produced dimeric aggregates via intermolecular ‐P=O…H‐N‐ hydrogen bonds, which in compound 2is a centrosymmetric dimer. In compounds with four‐membered ring amine groups, 3J(P,C)>2J(P,C), in agreement with our previous studies about five‐membered ring amine groups. Also, 3J(P,C) values in compounds 1and 5are greater than in compounds with five‐, six‐ and seven‐membered ring amine groups.

Using phosphoryl chloride as a substrate, a family of 1,3,2‐bis(arylamino) phospholidine, 2‐oxide of the general formula $\rm (X)(O)\overline{PN(Ar)CH_{2}CH_{2}N}(Ar)$; (X=Cl, 6a; X=NMe2, 1b; X=N(CH2C6H5)(CH3), 2b; X=NHC(O)C6H5, 3b; X=4Me‐C6H4O, 4b; X=C6H5O, 5b; X=NHC6H11, 6b; X=OC4H8N, 7b; X=C5H10N, 8b; X=NH2, 9b; X=F, 10band Ar=4Me‐C6H4) was prepared and characterized by 1H, 19F, 31P and 13C NMR and IR spectroscopy, and elemental analysis. A general and practical method for the synthesis of these compounds was selected. The structures of 6aand 2bwere determined by single‐crystal X‐ray diffraction techniques. The low temperature NMR spectra of 2brevealed the restricted rotation of P‐N bond according to two independent molecules in crystalline lattice.

Some new phosphoramidates were synthesized and characterized by 1H, 13C, 31P NMR, IR spectroscopy and elemental analysis. The structures of CF3C(O)N(H)P(O)[N(CH3)(CH2C6H5)]2(1) and 4‐NO2‐C6H4N(H)P(O)[4‐CH3‐NC5H9]2(6) were confirmed by X‐ray single crystal determination. Compound 1forms a centrosymmetric dimer and compound 6forms a polymeric zigzag chain, both via ‐N‐H…O=P‐ intermolecular hydrogen bonds. Also, weak C‐H…F and C‐H…O hydrogen bonds were observed in compounds 1and 6, respectively. 13C NMR spectra were used for study of 2J(P,C) and 3J(P,C) coupling constants that were showed in the molecules containing N(C2H5)2and N(C2H5)(CH2C6H5) moieties, 2J(P,C)>3J(P,C). A contrast result was obtained for the compounds involving a five‐membered ring aliphatic amine group, NC4H8. 2J(P,C) for N(C2H5)2moiety and in NC4H8are nearly the same, but 3J(P, C) values are larger than those in molecules with a pyrrolidinyl ring. This comparison was done for compounds with six and seven‐membered ring amine groups. In compounds with formula XP(O)[N(CH2R)(CH2C6H5)]2, 2J(P,CH2)benzylic>2J(P,CH2)aliphatic, in an agreement with our previous study.

New phosphoramidates with the general formulae Me2NP(O)Cl(p-NHC6H4-R) (A) and Me2NP(O)(p-NHC6H4-R)2(B), where R = H, CH3and NO2, F, Cl, Br, I, were synthesized and characterized by 1H, 13C, 31P NMR and IR spectroscopy and elemental analysis. The electronic effects of donor, acceptor and neutral groups on nJPXcoupling constants (n = 2, 3; X = H, C) and phosphorus chemical shifts are discussed. NMR data show that only the 4-nitroaniline substituent resulted in the disappearance of all coupling (nJPX= 0.0 Hz). Two nearly linear correlations were obtained between para-substituent constants (σp) and phosphorus chemical shifts for the two series A and B.

Two new phosphoramidates with formula RC(O)NHP(O)[NH(tert‐C4H9)]2, R=C6H5, (1) and CCl3, (2) were synthesized and characterized by IR, 1H‐, 13C‐, 31P NMR, mass spectroscopy and elemental analysis. The structures confirmed by X‐ray single crystal determination. Compound 1appears as two conformers (1aand 1b) in solid state as well as solution. Both compounds (1and 2) exist in the polymeric chains in crystalline lattice produced by hydrogen bonding that for compound 1, there are two independent infinite chains; each of them composed of one of the two conformers.

The examination of spectra of a selected series of phosphoramidates showed that, in addition to a double bond, whenever there are one or two partial multiple bonds in the molecule the long-range coupling constant, such as ⁶JP–H, ⁷JP–H and ³JP–H, either disappears or at least reduces. In particular, the experimental data indicate the unexpected effect of a partial multiple bond between phosphorus and fluorine in ⁷JP–H and ³JP–H. The preparation of the compounds p-CH3C6H4NHP(O)Cl2 (II), p-CH3C6H4NHP(O)(Cl)OC6H4CH3-p (XIV), m-CH3C6H4NHP(O)(Cl)OC6H4CH3-p (XV), m-CH3C6H4NHP(O)(Cl)OC6H4CH3-m (XVI) and the rigid molecule CH3C6H3(NH)2P(O)Cl (XVII) are described and they are characterized by ¹H, ¹³C, ³¹P NMR, IR spectroscopy and elemental analysis. Copyright © 2001 John Wiley & Sons, Ltd.

Matrix samples of F-CO-N3, and X-CO-NF2(X = H, NF2, CF3) were photolyzed by mercury arc light and the new infrared bands at 2172, 861, 695, 646, 529 cm-1assigned to the F-NCO molecule. 15N isotopic substitution confirmed the assignment of the IR bands of the new compound.

The nature of instability of sulfur dichloride was examined in the gas phase. Purification of this compound was performed by trap-to-trap condensation in the absence of light. In this condition, sulfur dichloride was quite stable for several days at room temperature and even up to 80°C in gas phase. The UV-Vis and IR spectra of the compound were reinvestigated. New data on the electronic absorption spectra of pure sulfur dichloride were obtained. Our observations reveal that the instability of sulfur dichloride is due to its photochemical decomposition until establishment of the equilibrium: 2SCl2 ⇆ S2Cl2+Cl2

Synthesis of 4-methylphenyl esters of N,N-dimethyl phosphoramidochloridic acid (1) and N,N-dimethyl phosphoramidofluoridic acid (2) is reported. 18-Crown-6 with potassium fluoride was found an effective reagent for the conversion of 1 to 2. These compounds were characterized by using 1H, 31P NMR, infrared and mass spectroscopic data. Analysis of the 1H NMR spectrum of ester 1 gives a long-range 31P-1H spin spin coupling (7JP-H = 1.2 Hz). A possible explanation for this unusual seven-bond coupling is discussed. In this study, a reasonable correlation between 31P chemical shifts and P=O vibration frequencies is suggested.

New 1,3,2-diazaphosphorinanes with the formula (X = F (1), Cl (2), Br (3), and I (4)) were synthesized and characterized by 1H, 13C, and 31P NMR and IR spectroscopy, and elemental analysis. The structures have been determined for compounds 3and 4by X-ray crystallography.

The compounds (III), (V), and (VII) are screened in vitro for their cytotoxic effects against the human cancer cell lines K562, MDA‐MB‐231, and HepG2.

Borax‐supported POCl3efficiently catalyzes the synthesis of 1,5‐benzodiazepine derivatives (9 examples) via condensation of o‐phenylenediamines with ketones both in solvent‐free and solution conditions.

Various β‐acetamido ketones are obtained by a one‐pot reaction of aryl aldehydes, enolizable ketones, acetyl chloride, and acetonitrile in a solvent‐free medium using borax‐supported POCl3as catalyst.

AbstractIn 13NMR study organophosphorus compounds, sign and magnitude of 13C-31P spin-spin couplings has been of great interest to elucidate stereochemistry and electronic state of phosphorus central atom. However, a discussion about the mechanisms of carbon-phosphorus couplings is still complicated specially in the case of long-range couplings that also are not frequently observed. In this study, 13C NMR chemical shifts and coupling constants have been determined for a series of aryl esters of phosphoramidochloridic acid with the general formula: R2NP(O)(OAr)Cl, in which R = methyl and/or benzyl, Ar = p-tolyl. p-nitrophenyl, and phenyl. Besides usual W-couplings that could be found in these systems, we detected long-range couplings through five and six bonds. It has been shown that, these couplings are highly dependent on substituents on phosphorus nuclei. The data for some related compounds have been also obtained for a comparison.