Reactions of 3-Hydroxy-2-phenyl-1H-benzo[e]isoindol-1-one: A Route to 3-Hydroxy-/3-anilinobenzo[e]indan-1-ones and Benzo[f]phthalazin-1(2H)-ones

New hydroxy- and anilinoindanone derivatives 3 and 4 were synthesized starting from 3-hydroxybenzo[e]isoindolinone 1 via the addition of alkyllithium (s-BuLi, n-BuLi, MeLi or i-PrLi) to the carbonyl group, followed by lactam ring opening and, finally, an intramolecular cyclization leading to target compounds. The same starting material was used for the preparation of the new benzo[f]phthalazinone derivatives 12–16 through multi-step reactions. The target derivative 16 was obtained from the corresponding bromolactam 15 by the Buchwald–Hartwig amination. Structures of the obtained compounds were confirmed by the NMR spectra.     

Synthesis and antineoplastic properties of (1H-1,2,3-triazol-1-yl)furazans

A method of 3-amino-4-[5-aryl(heteroaryl)-1H-1,2,3-triazol-1-yl)]furazan synthesis was optimized. Condensation of these compounds with 2,5-dimethoxytetrahydrofuran resulted in a series of previously unknown 4-[5-aryl(heteroaryl)-1H-1,2,3-triazol-1-yl)]-3-(pyrrol-1-yl)furazans. All target compounds were evaluated for both antimitotic microtubule destabilizing effect in a phenotypic sea urchin embryo assay and cytotoxicity in a panel of 60 human cancer cell lines. Pyrrolyl derivatives of triazolylfurazans were determined as antiproliferative compounds. The most potent microtubule targeting compounds 7a and 7e are of interest for further trials as antineoplastic agents.     

Stereoselective synthesis of 1-C-alkyl iminogalactitol derivatives,potential chaperones for galactosidase-linked LSDs: a real challenge

1-C-Alkyl iminogalactitol derivatives are highly desirable target compounds as potential pharmacological chaperones for the treatment of galactosidase-linked lysosomal storage disorders (LSDs). The synthesis of such compounds from d-galactose by a C-1 chain extension process by way of an open-chain 6-amino d-gulo nonulose intermediate was complicated by unexpected deoxygenation reactions leading to 3-deoxy iminogalactitol derivatives and epimers; an alternative, stereocontrolled synthesis from an l-tagatose derivative by C-6 chain-extension was therefore developed, which involved addition of organometallic reagents onto t-butanesulfinylimine intermediates in the key step.     

Synthesis,cytotoxic activity,and fluorescence properties of a set of novel 3-hydroxyquinolin-4(1H)-ones

The targeted solid-phase synthesis of 3-hydroxyquinolin-4(1H)-one derivatives is described. Primary and secondary amines, 3-amino-4-(methoxycarbonyl)benzoic acid and 2-bromo-1-(4-chloro-3-nitrophenyl)ethanone were used as starting materials. The structures of the final compounds were designed in accordance with previous information obtained from structure–activity relationship studies of similar cytotoxic derivatives. Representative prepared compounds were subjected to in vitro screening of cytotoxic activity against various cancer cell lines; the results obtained are discussed. Fluorescence properties of selected compounds were also studied to compare the data with those obtained in analogous derivatives.     

Synthesis of 1-thio-phytosphingolipid analogs by microwave promoted reactions of thiols and aziridine derivatives

A practical and versatile method for the synthesis of 1-thio-phytosphingolipid analogs through regioselective nucleophilic ring-opening reactions of phytosphingosine aziridine derivatives with thiols is described. The reactions were carried out with N-acylaziridines and a variety of thiol compounds. Microwave irradiation highly improved the yield of the ring-opening reaction and the intermediate N-acyl adducts were converted into 1-S-phytosphingolipid analogs, such as phytoceramide and phytosphingosine derivatives.     

Beiträge zur chemie des bors: 132. 1-phospha- und 1-arsa-4-bora-cyclohexadiene-2,5

The radical-initiated hydrophosphination and hydroarsination of diethylamino-dialkynylboranes with C₆H₅EH₂ (E = P, As) give the compounds 1-phospha- and 1-arsa-4-boracyclohexadienes-2,5 (IV and V, respectively). V is further reduced by C₆H₅AsH₂ to its dihydro derivative. Rather narrow boundaries exist for a substitution chemistry at the BN bond in IVa/IVb: methanolysis yields the B-methoxy derivative which in turn can be converted into the t-butyl compound. Alkali metals cleave the exocyclic PC bond. The anion formed reacts with RX yielding P-alkyl derivatives. Chalcogens convert the phosphorus(III) derivatives into phosphorus(V) compounds.     

Synthesis of derivatives of pyrrolo[1, 2-α]pyrmidine

Continuing investigations in the field of the synthesis of condensed heterocyclic systems containing pyrrole and indole fragments ¦1–3¦, we have condensed of 2-aminopyrrole derivatives with various 1, 3-dicarbonyl compounds. The reaction took place at the boil in solutions in pyridine or acetic acid, and also without a solvent at 150–160° C, forming in a single stage derivatives of pyrrolo[1, 2-a]pyrimidine (I–III) and pyrrolo[2, 1-b]-tetrahydroquinazoline (IV–VI). The condensation of 2-aminopyrrole with acetoacetic and substituted acetoacetic esters led to 4-oxo derivatives of pyrrolo[1, 2-β]pyrimidine (VII and VIII).     

1-Acylmethylbenzimidazole-2-sulfonic acids and their cyclization by N-nucleophiles

New preparation method was developed for derivatives of 1,4-dihydro-1,2,4-triazino[4,3-a]-, 2-aryl-1(9)H-, and 1-R-imidazo[1,2-a]benzimidazole underlain by newly synthesized 1-acylmethylbenzimidazole-2-sulfonic acids. The latter react with 2-aminoethanol affording along with the previously described compounds of the 1-(2-hydroxyethyl)imidazobenzimidazole series also compounds of formerly unknown polycyclic system, 2,3,11,12-tetrahydro-1,3-oxazolo[2,3-a]imidazo[1,2-a]benzimidazole.     

A one-pot synthesis of isoindolin-1-imine derivatives

A one-pot procedure was developed for the synthesis of isoindolin-1-imine derivatives by a simple three-component condensation of 2-cyanobenzaldhyde, ammonium acetate, and 4-hyroxycoumarin derivatives or 1,3-dicarbonyl compounds or 4-hydroxyquinolin-2(1H)-one in ethanol under reflux for 20–60 min with excellent yields. The advantages of this procedure are operational simplicity, excellent yields, and short reactive time, without catalyst, easy workup, and green environmental impact.     

Reactions of 6-methoxy-1,2,3,4-tetrahydro-β-carbolin-1-ones and their dichlorophosphoryl-substituted derivatives with acetic anhydride

2-Benzyl-, 9-benzyl-, and 2,9-dibenzyl-6-methoxy-1,2,3,4-tetrahydro-β-carbolin-1-ones were synthesized. It is shown that 6-methoxy-1,2,3,4-tetrahydro-β-carbolin-1-one and its 2- and 9-monobenzyl-substituted derivatives react with phosphorus oxychloride to give dichlorophosphoryl derivatives in which the dichlorophosphoryl residue enters into the composition of the cation and is bonded to the oxygen in the 1 position or (in the case of the pyrrole-nitrogen-unsubstituted compounds) the nitrogen atom in the 9 position. The possibility of acetylation of the dichlorophosphoryl compounds in the 5 position with acetic anhydride under mild conditions to give high yields of products was observed. The regularities in the mass spectra and PMR spectra of the β-carbolinone derivatives were exposed.     

In Vitro Inhibition Effect of Some Dihydroxy Coumarin Compounds on Purified Human Serum Paraoxonase 1 (PON1)

Human serum paraoxonase 1 (PON1; EC 3.1.8.1) is a high-density lipoprotein associated, calcium-dependent enzyme that hydrolyses aromatic esters, organophosphates and lactones and can protect the low-density lipoprotein against oxidation. In this study, in vitro inhibition effect of some dihydroxy coumarin compounds namely 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (A), 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (B) and 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (C) on purified PON1 were investigated by using paraoxon as a substrate. PON1 was purified using two-step procedures, namely ammonium sulphate precipitation and Sepharose-4B-l-tyrosine-1-naphthylamine hydrophobic interaction chromatography. The purified enzyme had a specific activity of 11.76?U/mg. The dihydroxy coumarin derivatives of A and B compounds inhibited PON1 enzyme activity in a noncompetitive inhibition manner with K _i of 0.0080?±?0.256 and 0.0003?±?0.018?mM values, respectively. C compound exerted an uncompetitive inhibition of PON1 enzyme activity with K _i of 0.0010?±?0.173?mM. Moreover, dihydroxy coumarin derivatives of A, B and C compounds were effective inhibitors on purified human serum PON1 activity with IC₅₀ of 0.012, 0.022 and 0.003?mM values, respectively. IC₅₀ value of unsubstituted 6,7 dihydroxy coumarin was found as 0.178?mM. The present study has demonstrated that PON1 activity is very highly sensitive to studied coumarin derivatives.     

The synthesis of blue emitting 3-Amino-1-hetarylfluorenes and their unprecedented alkylated derivatives

Novel 3-Amino-1-hetarylfluorene derivatives have medicinal uses and challenging transformation in organic synthesis have been synthesized via decyanation process. Surprisingly, the alkylated compounds derived from 3-Amino-1-hetarylfluorenes were obtained via further nucleophilic substitution to the 9-C and 3-N positions of the fluorene ring because of the harsh reaction condition employed. The synthesized compounds were characterized by spectroscopic techniques as well as X-ray single crystal diffraction analysis. This new family of blue emitting fluorene derivatives have low to moderate quantum yields (the largest value of Φ_F = 0.52 for compound 15).     

Discovery of Quinazoline-2,4(1H,3H)-Dione Derivatives as Potential Antibacterial Agent: Design,Synthesis, and Their Antibacterial Activity

In this paper, we report on the design and synthesis of a novel series of quinazoline-2,4(1H,3H)-dione derivatives as fluoroquinolone-like inhibitors of bacterial gyrase and DNA topoisomerase IV to identify and develop antimicrobial agents to prevent bacterial resistance problems. Their structures were confirmed using spectroscopic analyses (IR, NMR, and EI-MS). The novel quinazoline-2,4(1H,3H)-dione derivatives were evaluated for their antimicrobial activities against Gram-positive and Gram-negative bacterial strains using the Agar well diffusion method to study the antimicrobial activities and compared them with the standard drugs. Most compounds displayed moderate activity. Among the tested compounds, the most promising compounds 13 and 15 provided broad bioactive spectrum against Gram-positive and Gram-negative strains compared to the standard drugs.     

Application of cyclic sulfates in the synthesis of enantiomers of 1-[3-(4-aryl-piperazin-1-yl)-2-hydroxy-propyl]-pyrrolidin-2-one

The synthesis of enantiomers of 1-[3-(4-aryl-piperazin-1-yl)-2-hydroxy-propyl]-pyrrolidin-2-one derivatives is described. These enantiomers were synthesized starting from (R)- or (S)-1-chloro-2,3-dihydroxypropane using relevant cyclic sulfates as chiral intermediates. The enantiomeric purities of the final compounds were in the range of 99.3–100.0%, as determined by high performance liquid chromatography. The final compounds were found to display moderate potency as ligands for α₁-adrenoreceptors.     

Divergent synthesis of arylated pyridin-2(1H)-one derivatives via metal-catalysed cross-coupling processes

1,5-Di(hetero)arylated-pyridin-2(1H)-one derivatives have been readily obtained in good yields starting from 2-fluoro-5-pyridylboronic acid. The sequence comprises three steps: (i) palladium-catalysed Suzuki-Miyaura reaction; (ii) base-catalysed hydrolysis; (iii) copper-catalysed C-N coupling. X-ray crystal structures are reported for selected pyridin-2(1H)-one derivatives. These compounds are of interest as new scaffolds for drug discovery.     

Investigation of the Anticancer Effect of α-Aminophosphonates and Arylidine Derivatives of 3-Acetyl-1-aminoquinolin-2(1H)-one on the DMBA Model of Breast Cancer in Albino Rats with In Silico Prediction of Their Thymidylate Synthase Inhibitory Effect

Breast cancer is a major cause of death in women worldwide. In this study, 60 female rats were classified into 6 groups; negative control, α-aminophosphonates, arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one, DMBA, DMBA & α-aminophosphonates, and DMBA & arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one. New α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one were synthesized and elucidated by different spectroscopic and elemental analysis. Histopathological examination showed marked proliferation of cancer cells in the DMBA group. Treatment with α-aminophosphonates mainly decreased tumor mass. Bcl2 expression increased in DMBA-administered rats and then declined in the treated groups, mostly with α-aminophosphonates. The level of CA15-3 markedly declined in DMBA groups treated with α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one. Gene expression of GST-P, PCNA, PDK, and PIK3CA decreased in the DMBA group treated with α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one, whereas PIK3R1 and BAX increased in the DMBA group treated with α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one. The molecular docking postulated that the investigated compounds can inhibt the Thymidylate synthase TM due to high hydrophobicity charachter.     

Synthesis,spectral characterization and electrochemical properties of 1H-3-(o-, m- and p-ferrocenylphenyl)-1-phenylpyrazole-4-carboxaldehydes

New ferrocene derivatives – 1H-1-phenylpyrazole-4-carboxaldehydes containing o-, m- and p-ferrocenylphenyl group at position 3 – were synthesized and characterized. The electrochemical investigation showed that the position of the ferrocenyl group does not affect the redox potential of these compounds. The X-ray crystal structure of the ortho-derivative is also presented. The screening for the in vitro antimicrobial activity against eleven bacterial and three fungal/yeast strains exhibited complete inactivity of these aldehydes, but n-butyl imines of ortho and meta derivatives showed moderate activity compared to those of the used standards.     

Eco-friendly synthesis of guanidinyltetrazole compounds and 5-substituted 1H-tetrazoles in water under microwave irradiation

We have developed simple, short time, cost effective, purification of products by non-chromatographic methods and environmentally benign protocol for the synthesis of guanidinyltetrazoles and 5-substituted 1H-tetrazoles derivatives via [2,3]cyclo-addition reaction of nitriles and azide derivatives in water under microwave irradiation. All the synthesized products are screened for their in vitro antimicrobial activity. The synthesized compounds were obtained in excellent yield (85–98%).     

Synthesis and biological activities of new 1H-1,2,4-triazole derivatives containing ferrocenyl moiety

Some new 1H-1,2,4-triazole derivatives containing ferrocenyl moiety were synthesized in various yields by the condensation of ferrocenecarboxaldehyde with 1-(1H-1,2,4-triazol-1-yl)-3-aryl-2-one in toluene. Their structures of all these new compounds have been confirmed with ¹H NMR, IR, MS and elemental analysis. Their results of bioassay showed that some title compounds exhibited some degree of antifungal and plant growth regulatory activities.