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This review gives an account of the coordination chemistry of supramolecular Schiff base polymer complexes. The synthesis and structures of Schiff base monomers and their polymer complexes were described. Spectral techniques like (IR, 1H-NMR) and thermal analysis were investigated. ESR spectral data provided information about their structure on the basis Hamiltonian parameters and degree of covalency. The ESR data in connection with the structures and the nature of the bonding in these polymer complexes were investigated. This kind of investigation is fundamentally important to the structural estimation of various metallo-enzymes. The thermal stability was investigated using thermogravimetric analysis. The results showed that the Schiff base polymer complexes are mostly more stable than the homopolymer. The corrosion inhibition efficiency in absence and presence of ligands of aluminium in HCl was studied. The antimicrobial activity of all metal complexes compounds has also been demonstrated.

A variety of new functionalized triazolopyrimidine derivatives (VI) and pyrimidothiadiazines (IV) are synthesized from thiobarbituric acid (I).

Aliterature review studies of physicochemical properties and reactivity of naphthyridine derivatives due to their broad spectrum activity. The research work still looking for the promising compound of these derivatives and also the aim of our studies to activate this area of research and propose these derivatives as a target compounds that could be oriented as pharmaceutical compounds in medicine.

This describes the syntheses of a series of target compounds (V) and (VI) (selected examples shown).

Chemical investigation of the Red Sea soft coral Sarcophyton auritum led to the isolation and structure elucidation of two new diterpene cembranoids; 2- epi -sarcophine ( 2 ) and (1 R ,2 E ,4 S ,6 E ,8 R ,11 R ,12 R )-2,6-cembradiene-4,8,11,12-tetrol ( 4 ), as well as two known diterpene cembranoids, reported for the first time from this species, namely sarcophine ( 1 ) and (+)-7α,8β-dihydroxydeepoxysarcophine ( 3 ). Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. The isolated cembranoids were found to display high cytotoxicity against HepG2 (liver cancer cell line) and MCF-7 (breast cancer cell line).

Ynimines are used as excellent precursors of metalated ketenimines generated in situ by the reaction with organolithium reagents or strong bases.

A modular indole synthesis based on an intramolecular 5-endo-dig carbocupration starting from readily available N-aryl-ynamides is reported. A variety of ynamides are converted to indoles in moderate to good yields and with varying substitution pattern on the indole ring. This further extends the synthetic utility of ynamides in organic synthesis and provides additional insights on the use of intramolecular carbometalation reactions.

Samples of the title compound with 0 ≤ x ≤ 1.0 are prepared by reaction of CdSO4, InCl3, and TeCl4 in aqueous NH3 solution (pH 9) followed by addition of NaBH4 solution (85 °C, 2 h) to reduce the formed hydroxide phase to the alloy.

The new title compounds (IV) and (VI) show high antibacterial and antifungal activities at low concentrations.

The present synthesis of substituted pyridine derivatives relies on the facile lithiation of N-alkynyl-N-Boc-protected allylamines with subsequent highly regioselective intramolecular 6-endo-dig carbolithiation.

Cannabisol (1), a unique dimer of Δ9-tetrahydrocannabinol (Δ9-THC) with a methylene bridge, was isolated from Cannabis sativa. This is the first example of a C-bridged dimeric cannabinoid. The structure of 1 was unambiguously deduced by HRESIMS, GCMS, and NMR spectroscopy. A plausible biogenesis of 1 is described.

A series of dihydrobenzo[h]quinazoline derivatives is synthesized starting from compounds (I), (IX) or (XVII).

We have developed an efficient and general synthesis of ynimines based on an oxidative cross-coupling between imines and alkynylcopper reagents. Upon simple addition of 1,2-dimethylimidazole in the presence of oxygen, these bench-stable, crystalline, and readily available polymeric compounds were found to be especially suitable reagents for the introduction of an alkynyl group into a wide range of ketimines at room temperature and under especially mild conditions.

Fused heterocycles (III), (V), and (VII) are synthesized by reaction of thione (I) or its methyl derivative with hydrazonoyl halides of type (II).

In all reactions carried out under conditions A), formation of azine by-products is observed.

A new series of 6,7-dihydro-thiazolo[3,2- a ][1,3]diazepines ( 9 – 12 ), benzo[ d ]thiazolo[5,2- a ][12,6]diazepines ( 19 – 21) and benzo[ d ]oxazolo[5,2- a ][12,6]diazepine ( 24 ) analogues were synthesized and evaluated for their anticonvulsant activity. Compounds ( E )-2-bromo-6,7-dihydro-thiazolo[3,2- a ][1,3]diazepine-8(5 H )-thione ( 12 ), 3-chloro-benzo[ d ]thiazolo[5,2- a ][12,6]diazepin-10-one ( 20 ), and 4-chloro-benzo[ d ]oxazolo[5,2- a ][12,6] diazepin-10-one ( 24 ) showed 100% protection against PTZ- and bicuculline-induced seizures; 70%, 33%, 70% protection against MES-induced tonic extension; and 70%, 66%, 100% protection against picrotoxin-induced convulsions, respectively. Compounds 12 , 20 , and 24 proved to act as GABA A receptor agonists, with ED 50 values of 252, 380, 251 mg/kg; TD 50 values of 398, 417, 355 mg/kg; PI values of 1.58, 1.09, 1.41; LD 50 values of 380, 617, 537 mg/kg and TI values of 1.51, 1.62, 2.14, respectively.

This critical review summarizes existing knowledge on the use of diazonium salts as a new generation of surface modifiers and coupling agents for binding synthetic polymers, biomacromolecules, and nanoparticles to surfaces. Polymer grafts can be directly grown at surfaces through the so-called grafting from approaches based on several polymerization methods but can also be pre-formed in solution and then grafted to surfaces through grafting onto strategies including “click” reactions. Several routes are also described for binding biomacromolecules through aryl layers in view of developing biosensors and protein arrays, while the use of aryl diazonium coupling agents is extended to the attachment of nanoparticles. Patents and industrial applications of the surface chemistry of diazonium compounds are covered. This review stresses the paramount role of aryl diazonium coupling agents in adhesion, surface and materials sciences (114 references).

The hitherto unreported pyrazole compound (III) and its derivative (V) undergo regioselective 1,3-dipolar cycloaddition with in situ prepared nitrilimines to afford the pyrazole structures (VII) and (X).

Coupling the diazonium salt of aniline derivatives with (chlorobenzoylmethylene)methylpyrimidinone furnishes the arylhydrazono derivatives (III) in good yields.

A variety of new 1,5-diphenylpyrazole derivatives substituted by different triazole or triazole bioisosteres at position 3 is synthesized and evaluated for their anti-estrogenic effects and their cytotoxic properties against estrogen-dependent tumor cell lines.

1-(2-Adamantyl-3-(5-arylhydrazono-6-methyl-4-oxopyrimidin -2-yl)guanidines, 2-(2-adamantylamino)-4-amino-s-triazine and its 6-chloromethyl derivative were prepared by cyclization of 1-(2-adamantyl)biguanide.HCl with ethyl 2-arylhydrazono-3-oxobutyrates, ethyl formate and ethyl chloroacetate, respectively. 1-(2-damantyl)-3-(4,5-dioxo-2-imidazolidinylidene)guanidine was used as intermediate for the synthesis of amides, hydrazide and azomethine derivatives of alkyl 2-(2-adamantylamino)-4-amino-s-triazine-6-carboxylates. The antimicrobial testing of the prepared compounds proved that an azomethine derivative was the most active. It showed a marked bacteriostatic effect against Staphylococcus aureus and Bacillus subtilis.

Kinetics of chemical and electrochemical reduction of some 4-arylidene-5-pyrazolones were studied. The chemical reduction was performed using aluminum hydride. The electrochemical reduction in 0.1 mol dm−3 TEAP/DMF was studied by cyclic and convolution potential sweep voltammetry at HDME. The title compounds exhibit two diffusion-controlled irreversible mono electronic cv waves. Both waves follow EC kinetics and they are attributed to the reduction of the pyrazolin carbonyl group. The kinetics of the chemical and electrochemical reduction were proposed and discussed in terms of the molecular structure of the subject arylidenes.

New 2,3-dihydroquinazolin-4(1H)-ones combined with either chalcone (III), pyrazole (IV), or thiazole (VIII) moieties are synthesized and evaluated for their analgesic and antiinflammatory activity.

A series of non-peptide competitive antagonists of the human IMR 90 fetal lung fibroblast bradykinin B2 receptor have been designed and synthesized. Compound 15 binds with an affinity constant Ki = 60 nM. The SAR leading to the design of these non-peptide antagonists is described.

Cyclohexyl-based chiral auxiliaries can be used effectively in an asymmetric Pictet-Spengler synthesis of tetrahydroisoquinoline, aporphine and protoberbine alkaloids. Using this strategy, concise asymmetric syntheses of (−)-laudanosine, (+)-glaucine and (+)-xylopinine have been accomplished.

Four different types of metallosupramolecular structures are distinguishable for the title complexes. These types are described as: (a) The metal complex could react with other metal ions as a ligand, (b) Dimerization occurs through Lewis acid and Lewis base interactions of the metal ion and the coordinated oxygen atom of the ligand with those of an adjacent molecule, (c) Dimerization and chain formation occur using the donor-acceptor behaviour of the oxovanadium (IV) ion, and (d) Molecular association occurs through the bridged fluoride. Types (b), (c) and (d) are self-assembly. Chemical understanding of those types could lead to designing, and establishing procedures for, the preparation of new metallosupramolecular structures of homo- and heterobinuclear (as well as polynuclear) metal complexes with similar or mixed ligands.

Three series of novel pyrazole derivatives 2b-d, 4a-d and 6a-d were synthesized via two step procedure that utilizes hydrazonoyl chlorides 1a-d and enaminones 3a-d and 5a-d, respectively as starting materials. The structures of all the newly synthesized products have been established on the basis of analytical and spectral data. Moreover, some of the products 2-6 were tested against HCV and Subacute Sclerosing Panencephalitis (SSPE). In addition, compounds 2-6 were also tested for the inhibition of peroxynitrite-induced tyrosine nitration and antioxidant activity. The tested compounds are highly effective at very low concentration as anti-HCV, SSPE antioxidant and anticancer in the following ascending order 2d, 4c, 6b, 3b, 6c, 4d, 2b, 2c, 2a, 6a, 5b, 5a, 3a, 4b and 5c. It is worth to mention that all tested compounds are more potent than the reference standards used for comparing activity. All the measurements revealed that the mechanism of action of the anti cancer activities of all the tested compounds is topoisomerase I inhibitor.

The transformation of D-glucose to 5,6-disubstituted 5,6-dihydro-2H-pyran-2-one 3, an analogue of the (5R)-C6-pyranoid part of the natural α,β-unsaturated-δ-lactones is described.

Bis(pyridinyl-2,3-dihydrooxadiazolyl)benzenes 5a-e and 9a, b are obtained in 25-85% yields by heating the corresponding bis(hydrazones) 4a-f and 8a, d in refluxing Ac2O–AcOH for 3–5 h, while the bi...

Enantiomerically enriched epoxides are useful intermediates that have found many applications in asymmetric synthesis, and development of efficient catalysts for asymmetric epoxidation has received considerable attention. In this manuscript we describe the design, preparation, and use of new highly selective iminium salt organocatalysts for asymmetric epoxidation, based around a chiral binaphthalene motif coupled with a chiral substituted dioxane moiety. The new catalysts have been tested in the catalytic asymmetric epoxidation of unfunctionalized alkenes, and provide up to 95 % ee. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)