Genetically encoded macrocyclic peptide libraries with unnatural pharmacophores are valuable sources for the discovery of ligands many targets interest. Traditionally, generation such employs “early stage” incorporation building blocks into chemically or translationally produced macrocycles. Here, we describe a divergent late-stage approach to starting from readily available material: genetical...

This article describe the applicability of 1,4-disulfopiperazine-1,4-diium chloride ([Piper-(SO3H)2].2Cl) as a green, versatile and Brönsted acidic ionic catalyst in the promotion of the synthesis of phthalazine derivatives via one-pot three component reaction between aromatic aldehydes, 1,3-diketone derivatives and phthalhydrazide under solvent-free reaction cond...

This article describe the applicability of 1,4-disulfopiperazine-1,4-diium chloride ([Piper-(SO3H)2].2Cl) as a green, versatile and Brönsted acidic ionic catalyst in the promotion of the synthesis of phthalazine derivatives via one-pot three component reaction between aromatic aldehydes, 1,3-diketone derivatives and phthalhydrazide under solvent-free reaction cond...

Treatment of a sulfide with catalytic amount 1,3-diketone in the presence silica sulfuric acid as co-catalyst and hydrogen peroxide (50% aq) stoichiometric oxidant leads to corresponding sulfoxide product. The reaction is effective for diaryl, aryl-alkyl dialkyl sulfides tolerant oxidisable sensitive functional groups. Investigations have shown that tris-peroxide 2, formed on pentane-2,4-dione ...

Molecular chains of four Co(II) ions stabilized by a bis-β-diketone/pyridyl ligand may be isolated or linked into molecular pairs of two semi-independent such units.

For the purpose of this review, strong hydrogen bonds have been defined on the basis of experimental data, such as OH stretching wavenumbers, νOH, and OH chemical shifts, δOH (in the latter case, after correction for ring current effects). Limits for O-H···Y systems are taken as 2800 > νOH > 1800 cm-1, and 19 ppm > δOH > 15 ppm. Recent results as well as an account of theoretical advances are p...

Three new resin glycosides, quamoclins V (1), VI (2), and VII (3) and a new tetrahydropyran derivative, quamopyran (4), were isolated from the seeds of Quamoclit pennata BOJER (Convolvulaceae). The chemical structures of these compounds were determined primarily on the basis of spectroscopic data. The carboxyl group of the aglycone, 11S-convolvulinolic acid, of 1 and 2 was linked intermolecular...

Genistein, daidzein, glycitein and quercetin are flavonoids present in soybean and other vegetables in high amounts. These flavonoids can be metabolically converted to more active forms, which may react with guanine in the DNA to form complexes and can lead to DNA depurination. We assumed two ultimate carcinogen forms of each of these flavonoids, diol epoxide form and diketone form. Density fun...

The synthetic route in this work is based on the classical Friedel-Crafts strategy, and began with 1,4-dimethoxybenzene (I), followed by alkylation and selective demethylation of 2-methoxy function in 0x0-acid (3). The orthoformylation to synthesize aldehyde (6) was based on the Reimer-Tieman reaction. Chain extension of this aldehyde required methylation of the hydroxyl group and condensat...