Synthesis and antimicrobialactivity of 2‐alkylcarbamato‐2,3‐dihydro‐5‐propylthio‐1H‐1,3,2‐benzodiazaphosphole 2‐oxides

Novel 2‐alkylcarbamato/thiocarbama‐to‐2,3‐dihydro‐5‐propylthio‐1H‐1,3,2‐benzodiazaphos‐phole 2‐oxides ( 4a–J ) were synthesized by cyclization of 4‐propylthio‐1,2‐phenylenediamine ( 3 ) with the corresponding dichlorophosphoryl carbamates/thiocarbamates ( 2a–J ) that were obtained by the addition of alcohols/thiols to isocyanatophosphoryl dichloride ( 1 ). The structures of the title compounds were confirmed by the ¹H, ¹³C, ³¹P NMR, and mass spectral studies. Some of these products were found to possess significant antimicrobial activity. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:336–340, 2000     

Crystallographic characterization of a stable 7‐phosphanorbornadiene‐7‐oxide: 2,3‐benzo‐1,4,5,6,7‐pentaphenyl‐7‐phosphabicyclo[2.2.1] hepta‐2,5‐diene‐7‐oxide

The stable 7‐phosphanorbornadiene derivative, 2,3‐benzo‐1,4,5,6,7‐pentaphenyl‐7‐phosphabicyclo[2.2.1]hepta‐2,5‐diene‐7‐oxide ( 1 ) was synthesized in 45% yield via the Diels‐Alder reaction of pentaphenylphosphole oxide and benzyne. The reaction occurs specifically to give a single isomer, which was characterized by use of X‐ray crystallography and ³¹P NMR spectroscopy. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:182–186, 2000     

The synthesis and characterization of 1,2‐O‐cyclohexylidene‐4‐aza‐8‐aminooctane and some of its transition metal complexes

1,2‐O‐Cyclohexylidene‐4‐aza‐8‐aminooctane (L) has been synthesized starting from 1‐chloro‐2,3‐O‐cyclohexylidene, which has been prepared by the reaction of epichlorohydrin with cyclohexanone. The complexes of this ligand with Co(II), Ni(II), Cu(II), and UO₂(VI) salts were prepared. The structures of the ligand and its complexes are proposed based on elemental analyses, IR, UV‐vis, ¹H, and ¹³C NMR spectra, magnetic susceptibility measurements, thermogravimetric analyses, and differential thermal analyses. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:254–260, 2000     

Synthesis and antibacterial activity of 2‐alkylcarbamato/trichloromethyl/chloroethoxy/aryloxy‐1,2,3,4‐tetrahydro‐1,3,2‐benzodiazaphosphorine 2‐oxides

Several 2‐trichloromethyl/2‐chloro‐ethoxy/2‐aryloxy‐1,2,3,4‐tetrahydro‐1,3,2‐benzodiaza‐phosphorine 2‐oxides ( 4a–d ), and 2‐alkyl/alkenyl/alkynylcarbamato 2‐oxides ( 7a‐f ) have been synthesized from reactions of equimolar quantities of 2‐aminobenzylamine ( 2 ) with various aryl or alkyl phosphorodichloridates ( 3b–d ), trichloromethylphosphonic dichloride ( 3a ) and dichlorophosphinyl carbamates ( 6a–f ) at 40–50°C in dry toluene in the presence of triethylamine. IR, ¹H, ¹³C, ³¹P NMR and mass spectral analyses were collected and analyzed and supported all structures. The title compounds were screened for antibacterial activity against Bacillus subtilis and Escherichia coli. Several of the agents exhibited significant activity in the assays. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:323–328, 2000     

Synthesis and biological activity of O,O′‐dialkyl‐5‐aryl‐1‐hydroxy‐2E,4E‐pentadienylphosphonates

A series of O,O‐dialkyl‐5‐aryl‐1‐hydroxy‐2E,4E‐pentadienylphosphonates with structures similar to that of abscisic acid were synthesized by the reactions of dialkyl phosphites with 5‐aryl‐2E,4E‐pentadienaldehydes. The structures of all new compounds have been confirmed by ¹H NMR, ³¹P NMR, and IR spectroscopy and by elemental analysis or MS. The configurations of carbon‐carbon double bonds were determined by X‐ray diffraction analyses. The bioassays showed that some of these compounds exhibit inhibitory activity on the elongation of wheat coleoptile. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:303–307, 2000     

Preparation and physical properties of poly(4,4′‐diamino‐3′‐carbamoylbenzanilide terephthalamide) and poly(4,4′‐diamino‐3′‐carbamoylbenzanilide isophthalamide) films

To prepare thermally stable and high‐performance polymeric films, new solvent‐soluble aromatic polyamides with a carbamoyl pendant group, namely poly(4,4′‐diamino‐3′‐carbamoylbenzanilide terephthalamide) (p‐PDCBTA) and poly(4,4′‐diamino‐3′‐carbamoylbenzanilide isophthalamide) (m‐PDCBTA), were synthesized. The polymers were cyclized at around 200 to 350 °C to form quinazolone and benzoxazinone units along the polymer backbone. The decomposition onset temperatures of the cyclized m‐ and p‐PDCBTAs were 457 and 524 °C, respectively, lower than that of poly(p‐phenylene terephthalamide) (566 °C). For the p‐PDCBTA film drawn by 40% and heat‐treated, the tensile strength and Young's modulus were 421 MPa and 16.4 GPa, respectively. The film cyclized at 350 °C showed a storage modulus (E′) of 1 × 10¹¹ dyne/cm² (10 GPa) over the temperature range of room temperature to 400 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 775–780, 2000     

NMR study of the coordinating behavior of 2,6‐bis(benzimidazol‐2′‐yl)pyridine

The coordination sites of 2,6‐bis(benzimidazol‐2′‐yl)pyridine ( 1 ) toward protons and the diamagnetic metal ions Li⁺, Na⁺, and Co³⁺ were investigated by NMR spectroscopy. Variable temperature ¹H and ¹³C NMR experiments were performed on 1 in order to evaluate the tautomeric equilibrium and hydrogen bonding. Imidazole dicoordinated aromatic nitrogen atoms were protonated by trichloroacetic acid and the three N‐dicoordinated atoms by fuming H₂SO₄. Reactions of the ligand 1 and benzimidazole 2 with metallic sodium or LiH afforded anionic species; the alkali metal ions appeared solvated by THF, but not by the ligands 1 or 2 . In contrast, reaction of 1 with Co(III) produces the stable cation [Co( 1 ‐H)₂]⁺ with cobalt ion coordinated by two molecules of the monodeprotonated ligand. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:392–398, 2000     

Synthesis and characterization of a novel reactive ladderlike 4,4′‐phenylene ether‐bridged polyvinylsiloxane

A novel soluble, reactive ladderlike 4,4′‐phenylene ether‐bridged polyvinylsiloxane (L) was synthesized successfully for the first time by a stepwise coupling polymerization (SCP) including hydrolysis and polycondensation. The monomer, 4,4′‐bis(vinyldimethoxysilyl)phenylene ether (M), was synthesized by Grignard reaction. The structures of the monomer and the polymer were characterized by infrared spectrometry (IR), nuclear magnetic resonance (¹H NMR, ¹³C NMR, ²⁹Si NMR), mass spectrometry (MS), differential scanning calorimetry (DSC), X‐ray diffraction (XRD), and gel permeation chromatography (GPC). It is proposed from the characterization data that the polymer possesses an ordered ladderlike structure. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2702–2710, 2000     

Structural and 31P NMR solution studies on some cyclic triphosphenium ions and their 2‐arsa‐analogues

Several new cyclic triphosphenium ions and their 2‐arsa‐analogues have been identified in solution by ³¹P NMR spectroscopy. The crystal and molecular structures of the cations 1a,b , as their hexachlorostannate (IV) salts have shown that the five membered heterocyclic rings are planar, whereas the cation 9b as its diphosphanedioxide‐bis[pentachlorostannate(IV)] salt is nonplanar, like its saturated phosphorus counterpart. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:501–510, 2001     

Synthesis and characterization of the new ambidentate O‐cholesteryl‐O‐phenyl phosphorothioate ligand and its organoarsenic derivatives of phenoxarsin‐10‐yl and phenothiarsin‐10‐yl phosphorothioate

A new anionic phosphorothioate ligand that incorporates the bioactive cholesteryl group was obtained ( 2 ), Na(RR′P(S)O; R, O‐phenyl; R′, O‐cholesteryl) from the phenylphosphoramidate ( 1 ) and NaH in dioxane. In order to test the coordination ability of 2, two organoarsenic derivatives were prepared, O(C₆H₄)₂AsS(O)PRR′ ( 3 ) and S(C₆H₄)₂AsS(O)PRR′ ( 4 ) by reacting 2 with 10‐chlorophenoxarsine or 10‐chlorophenothiarsine. Compounds 2, 3 , and 4 were characterized by elemental microanalysis, IR, multi‐element NMR (¹H, ¹³C, and ³¹P), and mass spectrometry. The spectroscopic data suggest that the ligand is bonded to the arsenic only through the sulfur donor atom in both organoarsenic derivatives. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:6–10, 2000     

Kinetic and ESR studies on the radical polymerization of α‐n‐(α′‐methylbenzyl) β‐ethyl itaconamates derived from racemic and (s)‐α‐methylbenzylamines

The polymerization of α‐N‐(α′‐methylbenzyl) β‐ethyl itaconamate derived from racemic α‐methylbenzylamine (RS‐MBEI) by initiation with dimethyl 2,2′‐azobisisobutyrate (MAIB) was studied in methanol kinetically and with ESR spectroscopy. The overall activation energy of polymerization was calculated to be 47 kJ/mol, a very low value. The polymerization rate (R_p ) at 60 °C was expressed by R_p = k[MAIB]^0.5±0.05[RS‐MBEI]^2.9±0.1. The rate constants of propagation (k_p ) and termination (k_t ) were determined by ESR. k_p was very low, ranging from 0.3 to 0.8 L/mol s, and increased with the monomer concentration, whereas k_t (4–17 × l0⁴ L/mol s) decreased with the monomer concentration. Such behaviors of k_p and k_t were responsible for the high dependence of R_p on the monomer concentration. R_p depended considerably on the solvent used. S‐MBEI, derived from (S)‐α‐methylbenzylamine, showed somewhat lower homopolymerizability than RS‐MBEI. The k_p value of RS‐MBEI at 60 °C in benzene was 1.5 times that of S‐MBEI. This was explicable in terms of the different molecular associations of RS‐MBEI and S‐MBEI, as analyzed by ¹H NMR. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4137–4146, 2000     

Pendent polymers of 1‐methyl‐2‐oxo‐4,5‐dicyanoimidazole and their electrochemical properties

The electron accepting 1‐methyl‐4,5‐dicyanoimidazole group was attached to vinyl polymers, via an alkoxy link, by nucleophilic aromatic substitution (NAS) of 1‐methyl‐2‐fluoro‐4,5‐dicyanoimidazole ( 1 ) with poly(vinyl alcohol), or conventional polymerizations of vinyl monomers containing 1‐methyl‐2‐oxo‐4,5‐dicyanoimidazole. The cyclic voltammetry (CV) studies show that monomeric and oligomeric model compounds are electrochemically quasi‐reversible and the degree of reversibility decreases as dicyanoimidazoles become more proximate within a molecule. On the other hand, the polymers show much less reversible reduction waves at −2.6∼−2.7 V vs Ag/Ag⁺, suggesting that there are chemical reactions among the pendent groups reduced at relatively high potential. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3828–3838, 2000     

Synthesis of chiral 2‐oxo‐ and 2‐thio‐1,3,2‐oxazaphospholidines via the asymmetric cyclization of l‐serinoates with (thio)phosphoryl dichlorides

In this article, we have described the asymmetric cyclization of L‐serinoates and N‐benzyl L‐serinoate with phosphoro(no‐)dichloridates or their thio‐analog, respectively, and we have investigated the asymmetric induction effect of the chiral carbon center on the forming of a chiral phosphorus center. The diastereomeric excess percentages (de%) of the desired products 2‐oxo‐ and 2‐thio‐1,3,2‐oxazaphospholidines, are obtained based on their ³¹P NMR data. In some cases, the cyclization products have been separated as pure diastereomers by column chromatography. Their configuration is preliminarily discussed. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:187–191, 2000     

Syntheses,antitumor activities,and antiangiogenesis of exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalimidoethanoyl‐ 5‐fluorouracil and its polymers

A new monomer, exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalimidoethanoyl‐5‐fluorouracil (ETFU), was synthesized by the reaction of exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalimidoethanoyl chloride (ETPC) and 5‐fluorouracil (5‐FU). The homopolymer of ETFU and its copolymers with acrylic acid (AA) and vinyl acetate (VAc) were prepared via photopolymerizations with 2,2‐dimethoxy‐2‐phenylacetophenone at 25 °C for 48 h. The structures of the synthesized monomer and polymers were identified by Fourier transform infrared, ¹H NMR, and ¹³C NMR spectroscopy and elemental analysis. The ETFU contents in poly(ETFU‐co‐AA) and poly(ETFU‐co‐VAc) were 26 mol % and 26 mol %, respectively. The number‐average molecular weights of the polymers, as determined by gel permeation chromatography, ranged from 5600 to 17,000. The in vitro cytotoxicities of 5‐FU and the synthesized samples against mouse mammary carcinoma and human histiocytic lymphoma cancer cell lines increased in the following order: ETFU > 5‐FU > poly(ETFU‐co‐AA) > poly(ETFU) > poly(ETFU‐co‐VAc). The in vivo antitumor activities of the polymers against Balb/C mice bearing the sarcoma 180 tumor cells were greater than those of 5‐FU at all doses tested. The inhibitions of the samples for SV40 DNA replication and antiangiogenesis were much greater than the inhibition of the control. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4272–4281, 2000     

Synthesis of a new monomer N′‐(β‐methacryloyloxyethyl)‐2‐pyrimidyl‐(p‐benzyloxycarbonyl)aminobenzenesulfonamide and its copolymerization with N‐phenyl maleimide

The new monomer N′‐(β‐methacryloyloxyethyl)‐2‐pyrimidyl‐(p‐benzyloxy‐ carbonyl)aminobenzenesulfonamide (MPBAS) (M₁) is synthesized using sulfadiazine as parent compound. It could be homopolymerized and copolymerized with N‐phenyl maleimide (NPMI) (M₂) by radical mechanism using AIBN as initiator at 60 °C in dimethylformamide. The new monomer MPBAS and polymers were identified by IR, element analysis and ¹H NMR in detail. The monomer reactivity ratios in copolymerization were determined by YBR method, and r₁ (MPBAS) = 2.39 ± 0.05, r₂ (NPMI) = 0.33 ± 0.02. In the presence of ammonium formate, benzyloxycarbonyl groups could be broken fluently from MPBAS segments of copolymer by catalytic transfer hydrogenation, and the copolymer with sulfadiazine side groups are recovered. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2548–2554, 2000     

Influence of the stereochemical configuration on the radical polymerization of methacrylic monomers: cis‐ and trans‐(2‐cyclohexyl‐1,3‐dioxan‐5‐yl) methacrylate

The synthesis of two new isomeric monomers, cis‐(2‐cyclohexyl‐1,3‐dioxan‐5‐yl) methacrylate (CCDM) and trans‐(2‐cyclohexyl‐1,3‐dioxan‐5‐yl) methacrylate (TCDM), starting from the reaction of glycerol and cyclohexanecarbaldehyde, is reported. The process involved the preparation of different alcohol acetals and esterification with methacryloyl chloride of the corresponding cis and trans 5‐hydroxy compounds of 2‐cyclohexyl‐1,3‐dioxane. The radical polymerization reactions of both monomers, under the same conditions of temperature, solvent, monomer, and initiator concentrations, were studied to investigate the influence of the monomer configuration on the values of the propagation and termination rate constants (k_p and k_t ).The values of the ratio k_p /k_t ^1/2 were determined by UV spectroscopy by the measurement of the changes of absorbance with time at several wavelengths in the range 275–285 nm, where an appropriate change in absorbance was observed. Reliable values of the kinetics constants were determined by UV spectroscopy, showing a very good reproducibility of the kinetic experiments. The values of k_p /k_t ^1/2, in the temperature interval 45–65 °C, lay in the range 0.40–0.50 L^1/2/mol^1/2s^1/2 and 0.20–0.30 L^1/2/mol^1/2s^1/2 for CCDM and TCDM, respectively. Measurements of both the radical concentrations and the absolute rate constants k_p and k_t were also carried out with electron paramagnetic resonance techniques. The values of k_p at 60 °C were nearly identical for both the trans and cis monomers, but the termination rate constant of the trans monomer was about three times that of the cis monomer at the same temperature. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3883–3891, 2000     

Synthesis and characterization of new soluble polyamides from 1,1‐bis[4‐(4‐carboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane and various diamines

A new dicarboxylic acid monomer, 1,1‐bis[4‐(4‐carboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane, bearing a pendent tert‐butylcyclohexylidene group was prepared in three steps from 4‐tert‐butylcyclohexanone. The monomer was reacted with various diamines to produce a series of new polyamides with triphenyl phosphite and pyridine as condensing agents. These polyamides were produced with inherent viscosities of 0.74 to 1.02 dL g⁻¹. All the polymers were characterized by X‐ray diffraction that revealed this amorphous nature. These polymers exhibited excellent solubility in a variety of solvents. Almost all the polymers could be dissolved in N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, dimethyl sulfoxide, pyridine, and even in tetrahydrofuran and cyclohexanone. These polymers showed glass‐transition temperatures between 223 and 256 °C and decomposition temperatures at 10% weight loss ranging from 468 to 491 °C and 469 to 498 °C in nitrogen and air atmospheres, respectively. Transparent, tough, and flexible films of these polymers were cast from the DMAc solutions. These polymer films had tensile strengths ranging from 76 to 99 MPa, elongations at break from 7 to 19%, and initial moduli from 2.1 to 2.7 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 797–803, 2000     

Effect of cosolvent on the volume of activation for base hydrolysis of tris(1.10‐phenanthroline)‐ and tris (2.2′‐bipyridine)iron(II) complexes

The kinetics of the base hydrolysis of Fe(phen)₃²⁺ and Fe(bipy)₃²⁺ (phen = 1,10‐phenanthroline and bipy = 2,2'‐bipyridine) in some aqueous alcohol mixtures at ambient and elevated pressures (up to 1kbar) have been monitored spectrophotometrically at 25.0°C. For a given pressure, the alcohol cosolvent increases the rate of reaction relative to the reaction in a wholly aqueous medium. In all cases, increasing pressure causes rate retardation and derived volumes of activation for the reactions in aqueous solvent mixtures vary between +15 and +25 cm³ mol⁻¹, indicating that solvation changes of a different magnitude occur upon reaching the transition state from those occurring for the reactions in aqueous medium. Since the reaction has been established earlier to be nucleophilic attack of the incoming hydroxide ion, the volumes of activation signify marked increases in the loss of electrostricted solvent from the vicinities of the hydroxide ion and the iron(II) complex ions. © 2000 John Wiley & Sons, Inc. Int J Chem Kinet 32: 263–270, 2000     

Addition of isocyanides to α‐(methylthio)‐benzylidenamidinium iodides: A surprising access to 2‐(dialkylamino)imidazoles and 3,5‐diamino‐2H‐pyrrolium salts

A number of 2‐(dialkylamino)‐5‐(methylthio)imidazoles 2 are obtained by treating the formamidinium iodides 1a,b with isocyanides R³ NC under mild conditions. Reduction of these species can occur in the reaction medium to furnish the corresponding imidazoles 3 . In some cases, double cycloaddition across the imine bond of starting salts 1 also provides the (azetidin‐1‐yl‐methylene)ammonium iodides 4 . Reactions with tert‐butyl and isopropyl isocyanides in refluxing acetonitrile convert the acetamidinium iodide 1c into the 3,5‐diamino‐2H‐pyrrolium salts 7 . Mechanisms are suggested to account for these ring‐closure processes. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:370–376, 2000     

Radical polymerization of new functional monomer: Methacryloyl isocyanate containing 4‐chloro‐1‐phenol

New functional monomer methacryloyl isocyanate containing 4‐chloro‐1‐phenol (CPHMAI) was prepared on reaction of methacryloyl isocyanate (MAI) with 4‐chloro‐1‐phenol (CPH) at low temperature and was characterized with IR, ¹H, and ¹³C‐NMR spectra. Radical polymerization of CPHMAI was studied in terms of the rate of polymerization, solvent effect, copolymerization, and thermal properties. The rate of polymerization of CPHMAI has been found to be smaller than that of styrene under the same conditions. Polar solvents such as dimethylsulfoxide (DMSO) and N,N‐dimethyl formamide (DMF) were found to slow the polymerization. Copolymerization of CPHMAI (M₁) with styrene (M₂) in tetrahydrofuran (THF) was studied at 60°C. The monomer reactivity ratio was calculated to be r₁ = 0.49 and r₂ = 0.66 according to the method of Fineman—Ross. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 469–473, 2000