Synthesis and spectral properties of 2‐[(o‐ and p‐substituted)aminophenyl] ‐3H‐5‐[(o‐ and p‐substituted)phenyl]‐7‐chloro‐1,4‐benzodiazepines

A series of twelve new 2‐[(o‐ and p‐substituted)aminophenyl]‐3H‐5‐[(o‐ and p‐substituted)phenyl]‐7‐chloro‐1,4‐benzodiazepines, which have possible pharmacological properties has been obtained. The synthesis was carried out following six steps. The structure of all products was corroborated by ir, ¹H nmr, ¹³C nmr and ms. In addition for the compound 2‐(o‐chloroaminophenyl)‐3H‐5‐(o‐fluorophenyl)‐7‐chloro‐1,4‐benzodiazepine 7, its structure was confirmed by X‐ray diffraction.     

The Synthesis of 1,4‐Bis[N‐(4/6‐Substituted Benzothiazole‐2‐yl)‐N′‐Glycosylguanidino]Benzenes

The starting material O‐protected glycosyl isothiocyanate ( 1?3 ) was refluxed with 1,4‐diaminobenzene in CHCl₃ under nitrogen atmosphere to give 1,4‐bis(N‐glycosyl)thioureidobenzene ( 4?6 ). Then 1,4‐bis[N‐(4/6‐substituted benzothiazole‐2‐yl)‐N′‐glycosylguanidino]benzenes ( 8a?8e , 9a?9e , 10a?10e ) were obtained in good yield by reaction of compounds ( 4?6 ) with 2‐amino‐4/6‐benzothizoles ( 7a?7e ) and HgCl₂ in the presence of TEA in DMF. The structures of all 18 new compounds were confirmed by IR, ¹H NMR, LC‐MS and elemental analysis. The bioactivity of anti‐HIV‐1 protease (HIV‐1 PR) and against angiotensin converting enzyme (ACE) have been evaluated.     

Synthesis of a soluble conjugated cumulene polymer: poly(biphenyl‐4,4′‐diyl‐1,4‐bis(4‐dodecyloxyphenyl)‐buta‐1,2,3‐triene‐1,4‐diyl)

A conjugated polymer with a butatriene segment in the main chain, poly(biphenyl‐4,4′‐diyl‐1,4‐bis(4‐dodecyloxyphenyl)buta‐1,2,3‐triene‐1,4‐diyl), was synthesized from 1,4‐bis(4‐bromophenyl)‐1,4‐bis(4‐dodecyloxyphenyl)buta‐1,2,3‐triene by dehalogenative polycondensation using Ni(cod)₂. The polymer was well soluble in usual organic solvents such as CHCl₃ and THF. Structural analyses and characterizations were carried out by IR, NMR, UV‐Vis, PL, and Raman spectroscopy, as well as electrical conductivity. It is suggested that π‐conjugation is extended to some degree through biphenylylene and butatrienylene linkages.     

Synthesis of 5,6‐dihydro‐2‐trifluoromethyl‐1,4‐dioxin‐3‐carboxanilides through polymer‐bound activated ester: Construction of dihydro‐1,4‐dioxin

A new construction of dihydro‐1,4‐dioxin and a synthesis of 5,6‐dihydro‐2‐trifluoromethyl‐1,4‐dioxin‐3‐carboxanilides 22 through polymer‐bound activated ester are described. An intermediate β‐hydroxy ether 18 was prepared from the substitution reaction of α‐thio‐α‐chloro compound 8 with ethylene glycol followed by treatment with Raney Ni. Replacement of hydroxy by chlorine and then dehydrochlorination afforded trifluoromethyl dihydro‐1,4‐dioxin ester 15. The polymer‐bound trifluoromethyl dihydro‐1,4‐dioxin‐3‐carboxylic acid, 4‐hydroxy‐3‐nitrobenzophenone ester ( 21 ) was prepared through the reaction of polystyrene‐bound 4‐hydroxy‐3‐nitrobenzophenone ( 19 ) with the trifluoromethyl dihydro‐1,4‐dioxin‐3‐carbonyl chloride ( 20 ). Refluxing of 21 with substituted aniline in acetonitrile gave the corresponding carboxanilide 22. The reaction rate depended on the nucleophilicity of nitrogen of the aniline.     

A synchrotron radiation study of the one‐dimensional complex of sodium with (1S)‐N‐carboxylato‐1‐(9‐deazaadenin‐9‐yl)‐1,4‐dideoxy‐1,4‐imino‐d‐ribitol,a member of the 'immucillin' family

The sodium salt of [immucillin‐A–CO₂H]⁻ (Imm‐A), namely catena‐poly[[[triaquadisodium(I)](μ‐aqua)[μ‐(1S)‐N‐carboxylato‐1‐(9‐deazaadenin‐9‐yl)‐1,4‐dideoxy‐1,4‐imino‐d ‐ribitol][triaquadisodium(I)][μ‐(1S)‐N‐carboxylato‐1‐(9‐deazaadenin‐9‐yl)‐1,4‐dideoxy‐1,4‐imino‐d ‐ribitol]] tetrahydrate], {[Na₂(C₁₂H₁₃N₄O₆)₂(H₂O)₇]·4H₂O}_n, (I), forms a polymeric chain via Na⁺—O interactions involving the carboxylate and keto O atoms of two independent Imm‐A molecules. Extensive N,O—H...O hydrogen bonding utilizing all water H atoms, including four waters of crystallization, provides crystal packing. The structural definition of this novel compound was made possible through the use of synchrotron radiation utilizing a minute fragment (volume ∼2.4 × 10⁻⁵ mm⁻³) on a beamline optimized for protein data collection. A summary of intra‐ring conformations for immucillin structures indicates considerable flexibility while retaining similar intra‐ring orientations.     

Polymerization of (E)‐1,3‐Pentadiene and (E)‐2‐methyl‐1,3‐pentadiene with neodymium catalysts: Examination of the factors that affect the stereoselectivity

(E)‐1,3‐Pentadiene (EP) and (E)‐2‐methyl‐1,3‐pentadiene (2MP) were polymerized to cis‐1,4 polymers with homogeneous and heterogeneous neodymium catalysts to examine the influence of the physical state of the catalyst on the polymerization stereoselectivity. Data on the polymerization of (E)‐1,3‐hexadiene (EH) are also reported. EP and EH gave cis‐1,4 isotactic polymers both with the homogeneous and with the heterogeneous system, whereas 2MP gave an isotactic cis‐1,4 polymer with the heterogeneous catalyst and a syndiotactic cis‐1,4 polymer, never reported earlier, with the homogeneous one. For comparison, the results obtained with the soluble CpTiCl₃‐based catalyst (Cp = cyclopentadienyl), which gives cis‐1,4 isotactic poly(2MP), are examined. A tentative interpretation is given for the mechanism of the formation of the stereoregular polymers obtained and a complete NMR characterization of the cis‐1,4‐syndiotactic poly(2MP) is reported. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3227–3232     

Synthesis and nuclear magnetic resonance analysis of starch‐g‐poly(1,4‐dioxan‐2‐one) copolymers

A new biodegradable starch graft copolymer, starch‐g‐poly(1,4‐dioxan‐2‐one), was synthesized through the ring‐opening graft polymerization of 1,4‐dioxan‐2‐one onto a starch backbone. The grafting reactions were conducted with various 1,4‐dioxan‐2‐one/starch feed ratios to obtain starch‐g‐poly(1,4‐dioxan‐2‐one) copolymers with various poly(1,4‐dioxan‐2‐one) graft structures. The microstructure of starch‐g‐poly(1,4‐dioxan‐2‐one) was characterized in detail with one‐ and two‐dimensional NMR spectroscopy. The effect of the feed composition on the resulting microstructure of starch‐g‐poly(1,4‐dioxan‐2‐one) was investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3417–3422, 2004     

2‐(Pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone and 2‐phenyl­sulfanyl‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone

The structure of 2‐(pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone, C₁₄H_12.95Cl_0.05NO₂, (I), is actually a 0.95:0.05 mixture including 2‐chloro‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone as a minor impurity, but (I) was resolved as a single molecule containing a Cl atom with 5% occupancy at the 3‐position. Compound (I) was prepared from the fully chloro‐substituted analogue in an attempt to produce the disubstituted pyrrolidinyl derivative. 2‐Phenyl­sulfanyl‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone, C₂₀H₁₇NO₂S, (II), was also prepared from 2‐chloro‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphtho­quinone, using a strong exocyclic nucleophile. The structure of (II) differs from previous structures of 2,3‐di­chloro‐1,4‐naphtho­quinone and its derivatives in that the naphtho­quinone ring is non‐planar.     

Three‐component One‐pot Synthetic Route to Functionalized N‐Phenyl‐ and N,N‐(1,4‐phenylene)‐2‐alkylimino‐2,3‐dihydrothiazoles under Mild,Solvent‐ and Catalyst‐free Conditions

A simple and efficient one‐pot synthesis of alkyl‐2‐(alkylimino)‐4‐methyl‐3‐phenyl‐2,3‐dihydrothiazole‐5‐carboxylate and dialkyl 3,3′‐(1,4‐phenylene)‐bis‐[2‐(alkylimino)‐4‐methyl‐2,3‐dihydrothiazole‐5‐carboxylate] derivatives from the reaction of phenylisothiocyanate (and also 1,4‐phenylene diisothiocyanate) and primary alkylamines in the presence of 2‐chloro‐1,3‐dicarbonyl compounds is described. This new protocol has several advantages such as lack of necessity of the catalyst and solvent, good yields,mild conditions and short times for reaction.     

Synthesis and characterization of some new 4,4′‐(1,4‐phenylene)dipyrimidine and 6,6′‐(1,4‐phenylene)‐di(pyridin‐2(1H)‐one) derivatives

A series of new 4,4′‐(1,4‐phenylene)dipyrimidines 5a–c, 8a–c , and 10a,b have been synthesized from the reaction of amidines 1a–c with the dienaminone 2 , bis‐chalcone 6 , or ylidenemalono‐ nitrile 9 . The reaction of malononitrile and ethyl cyanoacetate with 2 gave 6,6′‐(1,4‐phenylene)di(pyridin‐2(1H)‐ones) ( 15a,b ). The structures of the products were proved by elemental analyses, IR, MS, ¹H, and ¹³C NMR spectroscopy. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:507–512, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20150     

Synthesis and spectral properties of 7‐chloro‐5‐[(o‐ and p‐R1)phenyl]‐1‐R2‐3H‐[1,4]benzodiazepin‐2‐ones

A series of twelve new 7‐chloro‐5‐[(o‐ and p‐R₁)phenyl]‐1‐R₂‐3H‐[1,4] benzo‐diazepin‐2‐ones, which have possible pharmacological properties were synthesized. The synthesis of all the final compounds was carried out by four steps. The structure of all final products was corroborated by ir, ¹H nmr, ¹³C nmr and ms, and have been obtained in 35‐94% yield.     

Chain composition dependence of luminescence properties for copolymers of 2‐methoxy‐5‐2′‐ethyl‐hexyloxy‐1,4‐phenylenevinylene and 2,3‐diphenyl‐5‐octyl‐1,4‐phenylenevinylene

The copolymers of 2‐methoxy‐5‐2′‐ethyl‐hexyloxy‐1,4‐phenylenevinylene (MEH‐PV) and 2,3‐diphenyl‐5‐octyl‐1,4‐phenylenevinylene were prepared via the Gilch route with their chain compositions and the reactivity ratios of the monomers estimated by ¹H NMR spectroscopy. The results indicated that the copolymers tended to form an alternative copolymer as the feed ratio of the monomers closed to one‐half. When an individual copolymer solution in tetrahydrofuran was spun‐cast to form a film, the MEH‐PV units were able to attract the like units from the adjacent chains. As a result, the ultraviolet–visible absorption spectrum of the alternative copolymer in film form was broader than the spectra of those with different compositions. The photoluminescence spectra of the copolymers in film form exhibited the characteristic shoulder of poly(2‐methoxy‐5‐2′‐ethyl‐hexyloxy‐1,4‐phenylenevinylene), even though the content of MEH‐PV units was not great enough for the formation of repeat units in sequence. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2180–2186, 2003     

New photoluminescent conjugated polymers with 1,4‐dioxo‐3,6‐diphenylpyrrolo[3,4‐c]pyrrole (DPP) and 1,4‐phenylene units in the main chain

A series of π‐conjugated polymers and copolymers containing 1,4‐dioxo‐3,6‐diphenylpyrrolo[3,4‐c]pyrrole (also known as 2,5‐dihydro‐3,6‐diphenylpyrrolo[3,4‐c]pyrrole‐1,4‐dione) (DPP) and 1,4‐phenylene units in the main chain is described. The polymers are synthesised using the palladium‐catalysed aryl‐aryl coupling reaction (Suzuki coupling) of 2,5‐dihexylbenzene‐1,4‐diboronic acid with 1,4‐dioxo‐2,5‐dihexyl‐3,6‐di(4‐bromophenyl)pyrrolo[3,4‐c]pyrrole and 1,4‐dibromo‐2,5‐dihexylbenzene in different molar ratios. Soluble hairy rod‐type polymers with molecular weights up to 21 000 are obtained. Polymer solutions in common organic solvents such as chloroform or xylene are of orange colour (λ_max = 488 nm) and show strong photoluminescence (λ_max = 544 nm). The photochemical stability is found to be higher than for corresponding saturated polymers containing isolated DPP units in the main chain. Good solubility and processability into thin films render the compounds suitable for electronic applications.     

The Synthesis of 2‐(Chromon‐2/3‐yl)‐3‐(5‐thione‐4‐hydro‐1,3,4‐thiadiazol‐2‐yl)‐4‐oxo‐thiazolidine

2‐Formylchromones and 3‐formylchromones as the first materials singly reacted with 2‐amino‐5‐mercapto‐1,3,4‐thiadiazole to give the corresponding Schiff bases, which on cyclocondensation with mercapto‐acetic acid in 1,4‐dioxane yielded target compounds named 4‐oxo‐thiazolidines. The structures of all the synthetic compounds were confirmed by elemental analysis and IR, ¹H NMR, LC‐MS (ESI) spectral data.     

Ultrasound‐Promoted Catalyst‐Free Synthesis of 2,2′‐(1,4‐Phenylene)bis[1‐acetyl‐1,2‐dihydro‐4H‐3,1‐benzoxazin‐4‐one] Derivatives

A convenient approach to 2,2′‐(1,4‐phenylene)bis[1‐acetyl‐1,2‐dihydro‐4H‐3,1‐benzoxazin‐4‐one] derivatives 4 was explored employing the one‐pot condensation of anthranilic acids (=2‐aminobenzoic acids) 1 with terephthalaldehyde (=benzene‐1,4‐dicarboxaldehyde; 2 ) under ultrasound‐irradiation conditions (Scheme 1). The reactions proceeded smoothly in the presence of excess Ac₂O in the absence of any other catalyst and solvent to afford the respective products in high yields.     

Synthesis,characterization and 1,3‐butadiene polymerization behaviors of cobalt complexes bearing 2‐pyrazolyl‐substituted 1,10‐phenanthroline ligands

A series of cobalt(II) complexes containing tridentate 2‐pyrazolyl‐substituted 1,10‐phenanthroline ligands (L) with the general formula [LCoCl₂] have been successfully synthesized and fully identified by IR spectroscopy, elemental analysis and mass spectroscopy. Cobalt complexes Co4–Co8 were further confirmed by X‐ray crystallographic analysis, and all the complexes adopted distorted trigonal pyramid geometries around the cobalt center. In combination with methylaluminoxane, the complexes exhibit high cis‐1,4‐selectivity for 1,3‐butadiene polymerization. The catalytic activities of the complexes mainly depend on the nature of the substituent and its position at the pyrazolyl ring of the ligand. Complexes having a bulkier substituent on the pyrazolyl ring of the ligand show lower catalytic activity and the incorporation of electron‐withdrawing substituent enhances the activity. Polymerization behaviors were almost not affected with varying [Al]/[Co] ratio, but both activity and the cis‐1,4 content decrease slightly as polymerization temperature increasing. Copyright © 2013 John Wiley & Sons, Ltd.     

Efficient synthesis and spectral determination of 11‐[(o‐ m‐ and p‐substituted)‐phenyl]‐8‐chloro‐3,3‐dimethyl‐2,3,4,5,10,11‐hexahydro‐1H‐dibenzo[b,e][1,4]diazepin‐1‐ones

A new synthesis to obtain eleven novel derivatives of 11‐[(o‐ m‐ and p‐substituted)‐phenyl]‐8‐chloro‐3,3‐dimethyl‐2,3,4,5,10,11‐hexahydro‐1H‐dibenzo[b,e][1,4]diazepin‐1‐ones with possible pharmacological activity in the central nervous system in two efficient steps has been developed. The final products were obtained by condensation and cyclization between 3‐[4‐chloro‐1,2‐phenylenediamine]‐5,5‐dimethyl‐2‐cyclohexenone with (o‐ m‐ and p‐substituted)benzaldehyde. The structure of all products was corroborated by ir, ¹H‐nmr, ¹³C‐nmr and high resolution in ms.     

Synthesis and Antimicrobial Activity of 2‐(4‐(Hydroxyalkyl)‐1H‐1,2,3‐triazol‐1‐yl)‐N‐substituted propanamides

A series of 21 2‐(4‐(hydroxyalkyl)‐1H ‐1,2,3‐triazol‐1‐yl)‐N ‐substituted propanamides (1,4‐disubstituted 1,2,3‐triazoles having amide linkage and hydroxyl group) have been synthesized from click reaction between terminal alkyne and 2‐azido‐N ‐substituted propanamide (generated in situ from reaction of 2‐bromo‐N ‐substituted propanamide and sodium azide) and characterized by FTIR, ¹H NMR, ¹³C NMR spectroscopy, and HRMS. All the newly synthesized triazoles were tested in vitro for antimicrobial activity against four bacterial cultures – Escherichia coli , Enterobacter aerogenes , Klebsiella pneumoniae , and Staphylococcus aureus – and two fungal cultures – Candida albicans and Aspergillus niger . The synthesized 1,4‐disubstituted 1,2,3‐triazoles displayed moderate to good antimicrobial potential against the tested strains.     

Synthesis of 2‐Aryl‐ and 2‐Heteroaryl‐3,5‐dimethoxy‐1,4‐benzoquinones Involving Pd‐Catalyzed Cross‐Coupling of (2,3,4,6‐Tetramethoxyphenyl)boronic Acid

A series of 2‐aryl‐ and 2‐heteroaryl‐substituted 3,5‐dimethoxy‐1,4‐benzoquinones (compounds 27 – 36 ) have been synthesized by cross‐coupling of (2,3,4,6‐tetramethoxyphenyl)boronic acid ( 2 ) with aromatic bromides or iodides in the presence of [Pd⁰(Ph₃)₄] and Na₂CO₃, followed by AgO‐promoted oxidation of the resulting biaryl compounds 17 – 26 .     

Blue photo‐ and electroluminescence based on poly(2‐benzoyl‐1,4‐phenylene) and poly(2,5‐dibenzoyl‐1,4‐phenylene)

Poly(2‐benzoyl‐1,4‐phenylene) (PBP) and poly(2,5‐dibenzoyl‐1,4‐phenylene) (PDBP) were synthesized by coupling polymerization using a Ni catalyst of 2,5‐dichlorobenzophenone and 2,5‐dichloro‐1,4‐dibenzophenone, respectively. These polymers are soluble in common organic solvents, have high thermal stability and show bright blue photoluminescence. Light‐emitting diodes fabricated with these polymers as the active layer emit blue electroluminescence with wavelength at 433 nm for PBP and 475 nm for PDBP. Copyright © 1999 John Wiley & Sons, Ltd.