Argentinian Rose Petals as a Source of Antioxidant and Antimicrobial Compounds.

The total phenolic, flavonoid, and anthocyanin contents were evaluated in 11 cultivars of Argentinian roses of different colors. HPLC-ESI-QTOF/MS was used to identify the components where ellagic and quinic acids, quercetin, and kaempferol glycosylated derivatives were found. The phenolic contents ranged from 78.8 ± 3.2 to 203.4 ± 3.1 mg GAE/g dw, the flavonoid content ranged from 19.1 ± 3.8 to 125.9 ± 6.5 mg QE/g dw, and the anthocyanin content ranged from less than 0.01 to 5.8 ± 0.1 mg CE/g dw. The dark red cultivars exhibited the greatest levels of the analyzed compounds and of the antioxidant activities, even higher than those of certain plants known for their high phenolic contents and antioxidant activity. Moreover, the addition of these extracts decreased the population of L. innocua and P. aeruginosa to undetectable levels 24 h after inoculation. Rose petal extracts, mainly those with a dark red color, can be used as natural additives in food, feed, and cosmetics, as they contain a high proportion of bioactive compounds with antioxidant and antimicrobial effects.

Synthesis and biological evaluation of new antiseizure compounds derived from valproic acid.

Background: New hybrid compounds were synthesized by linking the valproic acid (VPA) structure with other anticonvulsant/anti-inflammatory scaffolds. Materials & methods: The chemistry involved the incorporation of the linker oxymethyl ester into VPA, followed by reaction with the second scaffold. The antiseizure effects were investigated by the maximal electroshock seizure test, and the most active compound was additionally evaluated in the 6 Hz test and pentylenetetrazol test in mice. Results: The compounds showed protection against seizures. The hybrid structure with the butylparaben scaffold exhibited an ED50 of 8.265 mg/kg (0.0236 mmol/Kg) in the maximal electroshock seizure test and 50.00 mg/kg (0.147 mmol/kg) in the 6 Hz test. Conclusion: The antiseizure activity of the synthesized compounds highlighted the potential of hybrid structures to treat multifactorial diseases such as epilepsy.

This article focuses on the design of new anticonvulsant compounds that combine the chemical structure of valproic acid with other interesting scaffolds with anticonvulsant or anti-inflammatory properties. These compounds protected against in vivo acute seizure models (mice). The results revealed the capacity of combining known scaffolds into a single structure to generate new active compounds with multitarget purposes.

Effect of the Drying Method and Optimization of Extraction on Antioxidant Activity and Phenolic of Rose Petals.

The effect of freeze and hot air drying methods on the retention of total phenolics, antioxidant activity (AA), and color of different cultivars of rose petals was analyzed. Both methods similarly preserved the phenolic content and AA, while freeze drying showed better red color retention. Furthermore, the conditions of total phenolics and AA extraction from two rose cultivars, Lovely Red and Malu, were optimized by response surface methodology through a Box-Behnken design. The solvent exhibited a major effect on the total phenolic content (TPC) and AA. The selected parameters were ethanol 38%, 75 °C, and 30 min. Under these conditions, the predicted values for Lovely Red were 189.3 mg GA/g dw (TPC) and 535.6 mg Trolox/g dw (AA), and those for Malu were 108.5 mg GA/g dw (TPC) and 320.7 mg Trolox/g dw (AA). The experimental values were close to the predicted values, demonstrating the suitability of the model. Ultrasound-assisted extraction increased the AA of the extracts but not the TPC. Fifteen compounds were identified in the Lovely Red cultivar, with no differences between the two drying methods. The results obtained suggest that the analyzed cultivars, particularly the red ones, can be considered a natural source of powerful antioxidant compounds.

One-step synthesis of N,N'-substituted 4-imidazolidinones by an isocyanide-based pseudo-five-multicomponent reaction.

A pseudo-five-multicomponent reaction involving an isocyanide, a primary amine, two molecules of formaldehyde and water is reported, which gives N,N'-substituted 4-imidazolidinones when trifluoroethanol is used as the solvent. The reaction proceeds with good yields and with a wide variety of amines and isocyanides, providing an efficient new entry to these heterocycles. A preliminary study of the reaction mechanism suggests that trifluoroethanol, although acting as the solvent, is directly involved as a reagent in the reaction pathway.

Versatile supramolecular organogel with outstanding stability toward aqueous interfaces.

In this communication, we report on a novel and versatile low-molecular-weight organogelator. The methanolic gel exhibits an exceptional water-enhanced stability as evidenced by a 30 °C increase in Tg with up to 10%v/v of water. This atypical property not observed with other solvents makes of this supramolecular gel a highly stable matrix compatible with aqueous interfaces. As a proof of principle we present the sensing performance of a symmetric tricarbocyanine fluorophore bearing a Zn(II)chelator unit. The system retained its remarkable physical integrity for a long period of time opening new possibilities for other organic-aqueous interface applications.

QSAR on antiproliferative naphthoquinones based on a conformation-independent approach.

The antiproliferative activities of a series of 36 naphthoquinone derivatives were subjected to a Quantitative Structure-Activity Relationships (QSAR) study. For this purpose a panel of four human cancer cell lines was used, namely HBL-100 (breast), HeLa (cervix), SW-1573 (non-small cell lung) and WiDr (colon). A conformation-independent representation of the chemical structure was established in order to avoid leading with the scarce experimental information on X-ray crystal structure of the drug interaction. The 1179 theoretical descriptors derived with E-Dragon and Recon software were simultaneously analyzed through linear regression models based on the Replacement Method variable subset selection technique. The established models were validated and tested through the use of external test sets of compounds, the Leave-One-Out Cross Validation method, Y-Randomization and Applicability Domain analysis.

ß-Lapachone analogs with enhanced antiproliferative activity.

In this study, we describe the synthesis of a series of α- and ß-lapachone containing hydroxyl or methoxyl groups on the benzene ring, by means of the selective acid promoted cyclization of the appropriate lapachol analog. The evaluation of the antiproliferative activity in human solid tumor cell lines provided 7-hydroxy-ß-lapachone as lead with enhanced activity over the parent drug ß-lapachone. Cell cycle studies, protein expression experiments, and reactive oxygen species analysis revealed that, similarly to ß-lapachone, ROS formation and DNA damage are critical factors in the cellular toxicity of 7-hydroxy-ß-lapachone.

Antiproliferative activity of synthetic naphthoquinones related to lapachol. First synthesis of 5-hydroxylapachol.

A series of 5-hydroxy-1,4-naphthoquinones analogues was synthesized from juglone (6) and their antiproliferative activity against a representative panel of six human solid tumor cell lines has been investigated. The 2,5-dihydroxy-3-(3-methylbut-2-enyl)naphthalene-1,4-dione (4) and 2,3-dihydro-5-hydroxy-2-(prop-1-en-2-yl)naphtho[2,3-b]furan-4,9-dione (27) were the most potent antiproliferative agents with GI(50) values of 0.42-8.1 and 0.80-2.2microM, respectively. The results provide insight into the correlation between some structural properties of 5-hydroxynaphthoquinones and their antiproliferative activity.