Synthesis and antioxidant activity of novel vanillin-based ferrocenyl chalcones

A small series of new ferrocenyl chalcones was prepared, starting from the corresponding aldehydes and monoacetyl ferrocene. Di-derivatives of vanillin and ethylvanillin were prepared and used as aldehydes for this synthesis. All new compounds were characterized by IR and NMR spectroscopy and physical data. The antioxidant potential of new compounds was evaluated using the DPPH test and the results showed moderate activity in vitro.Publishe

Synthesis of N-acetyl and N-formyl pyrazoline derivatives from vanillin and their antigenotoxic activity

Vanillin is one of the most important natural products, used as a starting material in the new drug design procedures. Starting from vanillin, we can prepare different chalcones, which are known for their pronounced pharmacological and biological activities. For this reason some chalcone analogues have been synthesized from the corresponding vanillin derivatives. Further reaction with hydrazine in formic acid or acetic acid yielded 20 new pyrazoline compounds with N-formyl and N-acetyl groups, respectively. All new compounds were well characterized by IR, 1H and 13C NMR spectroscopy and physical data. In vitro DNA protective potential of selected compounds on hydroxyl and peroxyl radical-induced DNA damage was investigated. The results showed that the new synthesized compounds had expressed potential to prevent DNA damage.Publishe

Normal and Reversed Phases Thin-Layer Chromatography of Arylidene 2- Thiohydantoin Derivatives

In this paper, the retention behavior of thirteen newly synthesized arylidene derivatives of 2-hydamthione was investigated by normal and reversed phases thin-layer chromatography. In normal phase chromatography, thin layers of silica gel and cyano-propyl (CN) silica gel with fluorescent indicator F254 were used as the stationary phase. As the mobile phase, binary systems of non-aqueous solvents benzene-ethyl acetate and hexane-ethyl acetate were used, 8:2 (v/v). Reversed phase chromatography was performed using a thin layer of octadecyl (C-18) silica gel with fluorescent indicator F254 as the stationary phase and a binary solvent mixture of acetonitrilewater in the ratio 7.5:2.5 (v/v) as the mobile phase. Observing under a UV lamp, the spots of all tested derivatives were clearly visible. The RF value was determined for each spot. Based on the obtained results the HPLC technique is recommended for further chromatographic examination of the newly synthesized arylidene derivatives of 2-hydamthione, using commercial columns with polar chemically bound phases and both non-aqueous and aqueous eluents.Publishe

Supporting information for: Water-Tuned Tautomer-Selective Tandem Synthesis of the 5,6-Dihydropyrimidin-4(3 H )-ones, Driven under the Umbrella of Sustainable Chemistry

The selective synthesis of 5,6-dihydropyrimidin-4(3H)-one scaffold (precursor of dihydrouracil) was a very difficult synthetic challenge that, so far, has not been achieved. For the first time, in this paper, green, selective and high-yields approach to 40 novel 5,6-dihydropyrimidin-4(3H)-ones (DHPMs) by one-pot reaction of aldehydes, Meldrum's acid and isothioureas under solvent-free conditions, in the presence of water, since an additive is presented. In the majority of cases, introduced methodology gave an unprecedented tautomer-selective fashion toward targeted compounds with excellent tautomeric purity (>99.9%), which reached 100% in few cases. The molecular structure of the five compounds has been determined by X-ray crystallography. In each one of them, very short length for the corresponding N2-C1 bond was noticed, making them especially interesting from a structural standpoint. This experimental fact can imply a highly localized electron π density in this part of each heterocyclic ring. The obtained experimental results, which are determined from NMR and ESI-MS study, indicate that this Biginelli-type reaction smoothly proceeds in a one-pot mode, pointing to the three-step tandem process, proceeding via the Knoevenagel, aza-Michael, and retro-Diels-Alder reactions. The presented strategy also had the following advantages: reduction amount of waste, excellent values of green chemistry metrics (cEF, EcoScale and GCIS), and it is the first eco-friendly strategy toward the DHPMs scaffold. © Copyright 2018 American Chemical Society.Supplementary data for the article: [https://dx.doi.org/10.1021/acssuschemeng.8b03127]Related to: [http://vinar.vin.bg.ac.rs/handle/123456789/7886

Dehydrozingerone analogues: Reaction of O-alkyl derivatives of vanillin and methyl cyclopropyl ketone

O-Alkyl vanillines and methyl cyclopropyl ketone reacts under Claisen- Schmidt conditions yielding corresponding enone derivatives, dehydrozingerone analogues with cyclopropane ring fragment, (E)-1-cyclopropyl-3-(4-alkoxy-3- methoxyphenyl)prop-2-en-1-ones. All new compounds were well characterized by IR, 1H and 13C NMR spectroscopy and physical data

Synthesis and antimelanogenic activity of N3-aryliden-2-thiohydantoin derivatives

The main goal of this study was to synthesize novel potent and safe inhibitors of melanogenesis based on the 2-thiohydantoin moiety for therapeutic application in the treatment of skin hyperpigmentation disorders in humans (freckles, chloasma, melasma, solar lentigo, senile lentigines, ephelides and melanoderma). A series of 15 N3-aryliden-2-thiohydantoin derivatives was synthesized, fully characterized, and subjected to extensive in vitro and in vivo biological evaluation. All compounds have been tested on the zebrafish model, a powerful and highly predictive animal platform used for toxicity assessment and biological activity evaluation of novel bioactive molecules, thus simplifying the path to clinical trials and reducing the failure at later stages of testing. Their antimelanogenic activity and toxicity were compared to those of kojic acid and hydroquinone, well-known depigmenting agents used for the treatment of skin hyperpigmentation disorders. Most of the compounds reduced body pigmentation of the treated zebrafish embryos with different efficacy. Derivatives which exhibited the best melanogenesis inhibitory activity exerted much better therapeutic profile than kojic acid and hydroquinone, the former of which was non-toxic and poorly effective and the latter highly effective but extremely toxic. The presented results of biological activity evaluation in vivo clearly demonstrate that compounds with 2-thiohydantoin moiety could present a novel effective and safe antimelanogenic compounds with a large potential for further clinical evaluation and therapeutic application in humans.Publishe

4-[(4-Methylphenyl)sulfanyl]butan-2-one

In the title compound, C(11)H(14)OS, all non-H atoms are essentially coplanar, with a mean deviation of 0.023 Å. In the crystal, centrosymmetrically related mol­ecules are weakly connected into dimers by pairs of C—H⋯O inter­actions. The dimers are further linked along the a axis by weak C—H⋯π and C—H⋯S inter­actions

4-Ethoxy-3-methoxybenzaldehyde

In the title compound, C10H12O3, all non-H atoms are approximately coplanar, with an r.m.s. deviation of 0.046 Å. In the crystal, very weak C-H⋯O interactions link the molecules into sheets parallel to (101)