Synthesis of biological based hennotannic acid-based salts over porous bismuth coordination polymer with phosphorous acid tags

In this paper, a novel porous polymer capable of coordinating to bismuth (PCPs-Bi) was synthesized. The Bi-PCPs was then reacted with phosphorous acid to produce a novel polymer PCPs(Bi)N(CH(2)PO(3)H(2))(2) which is shown to act as an efficient and recyclable catalyst. The mentioned catalyst was applied for the efficient synthesis of new mono and bis naphthoquinone-based salts of piperidine and/or piperazine via the reaction of hennotannic acid with various aldehydes, piperidine and/or piperazine, respectively. The structure of the resulting mono and bis substituted piperazine or piperidine-based naphthoquinone salts was thoroughly characterized spectroscopically. The electrochemical behavior of the products was also investigated. The presented protocol has the advantages of excellent yields (82–95%), short reaction times (4–30 min) and simple work-up

Enhancing encapsulation of hydrophobic phyto-drugs naringenin and baicalein in polymeric nano-micelles

Pluronic micelles hold great potential to act as hydrophobic drug delivery carriers; however, there is a pressing need to optimize their use in commercial formulations. This is the first report that describes the loading of phyto-drugs naringenin (NAR) and baicalein (BAC) in different Pluronics F108, F127 and P84 using solvent evaporation method (S.Ev.M) and Direct dissolution method (D.D.M.). Pluronic P84 micelles were able to encapsulate significantly higher amount of both phyto-drugs as compared to other Pluronic micelles. S.Ev.M appreciably enhanced the encapsulation of NAR (19.2 ± 0.438 mg/mL) and BAC (2.593 ± 0.223 mg/mL) compared to D.D.M. (NAR, 10.95 ± 0.212 mg/mL, and BAC, 1.058 ± 0.049 mg/mL) in 5% w/v and 12% w/v Pluronic P84, respectively. SEM (Scanning Electron Microscopy) results showed a spherical morphology after the incorporation of NAR into Pluronic micelles and evidenced that S.Ev.M did not affect the morphology. Sustained release behavior of phyto-drugs was observed from the loaded Pluronic micelles, which was conformed via in vitro release studies. Finally, antioxidant activity was analyzed by ABTS•+ (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging assays, with both NAR and BAC loaded P84 micelles (IC50 7.185 and 28.90 μg/mL) showcasing a marked increase in antioxidant properties compared to the pure phyto-drugs NAR and BAC (IC50 13.25 and 53.68 μg/mL) or other Pluronic formulations. Interaction of phyto-drugs and Pluronic P84 has been screened using 1H NMR Spectroscopy (proton nuclear magnetic spectroscopy) and revealed that the whole NAR molecule was encapsulated within the Pluronic micelles. These phyto-drugs hold great potential for use as nutraceuticals and other pharmaceutical applications but currently can't be used due to poor solubilization. Therefore, it can be suggested that preparation of drug loaded Pluronic formulations using S.Ev.M. would be more convenient, fast, and efficient method over D.D.M

Synthesis of an Advanced Intermediate of the Jatrophane Diterpene Pl‑4: A Dibromide Coupling Approach

The preparation of an advanced intermediate toward the synthesis of the jatrophane diterpene Pl-4 is described. The key step is a regioselective chelation-controlled lithiation of the (<i>Z</i>)-configured bromide in the corresponding vinyl dibromide precursor. The method outlined within this Article is suitable for the facile access of sterically hindered internal vinyl halides for further coupling reactions

Fiber Spinning from Cellulose Solutions in Imidazolium Ionic Liquids: Effects of Natural Antioxidants on Molecular Weight, Dope Discoloration, and Yellowing Behavior

Spinning of cellulosic fibers requires the prior dissolution of cellulose. 3-Alkyl-1-methylimidazolium ionic liquids have proven to be suitable solvents for that purpose, but the degradation of cellulose in the spinning dope can be severe. Suitable stabilizers are therefore required that prevent cellulose degradation, but do not adversely affect spinnability or the long-term yellowing behavior of the fibers. A group of twelve renewables-based antioxidants was selected for stabilizing 5% cellulose solutions in the ionic liquids and their effects on cellulose integrity, dope discoloration, and aging behavior were tested by gel permeation chromatography (GPC) and ISO brightness measurements. Propyl gallate (a gallic acid derivative), hydroxytyrosol (from olives), and tocopheramines (a vitamin E derivative) performed best in the three test categories, minimizing both cellulose degradation, chromophore formation in the spinning dope, and yellowing upon accelerating aging of the spun fibers. The use of these stabilizers for cellulose solutions in the imidazolium-based solvent system can therefore be recommended from the point of view of both performance and sustainability

Structure–Activity Relationships, Ligand Efficiency, and Lipophilic Efficiency Profiles of Benzophenone-Type Inhibitors of the Multidrug Transporter P-Glycoprotein

The drug efflux pump P-glycoprotein (P-gp) has been shown to promote multidrug resistance (MDR) in tumors as well as to influence ADME properties of drug candidates. Here we synthesized and tested a series of benzophenone derivatives structurally analogous to propafenone-type inhibitors of P-gp. Some of the compounds showed ligand efficiency and lipophilic efficiency (LipE) values in the range of compounds which entered clinical trials as MDR modulators. Interestingly, although lipophilicity plays a dominant role for P-gp inhibitors, all compounds investigated showed LipE values below the threshold for promising drug candidates. Docking studies of selected analogues into a homology model of P-glycoprotein suggest that benzophenones show an interaction pattern similar to that previously identified for propafenone-type inhibitors

Specific activity of <i>S. coelicolor</i> Hms for a range of aliphatic 2-oxo acids and corresponding calculated substrate log <i>D</i> values.

<p>Measurements were performed in air saturated 20 mM Tris buffer at pH 7.5 and 25°C. Values for HPP are given in comparison. The limit of detection under assay conditions was a specific rate of 10⁻⁵ s⁻¹.</p

Preparation of α-oxo acids VII, VIII, and IX from the corresponding aromatic aldehydes.

<p>Preparation of α-oxo acids VII, VIII, and IX from the corresponding aromatic aldehydes.</p