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Search for "solubility" in Full Text gives 988 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Dipeptide analogues of fluorinated aminophosphonic acid sodium salts as moderate competitive inhibitors of cathepsin C
Beilstein J. Org. Chem. 2023, 19, 434–439, doi:10.3762/bjoc.19.33
- result of the reactions carried out, the dipeptide analogues of α- and β-fluorinated aminophosphonic acids 8 and 10 were obtained. All the samples were solids, with very poor solubility in water and organic solvents such as DMSO and MeOH. The final step of the synthesis was the reaction of the resulting
Combretastatins D series and analogues: from isolation, synthetic challenges and biological activities
Beilstein J. Org. Chem. 2023, 19, 399–427, doi:10.3762/bjoc.19.31
- bond of 28 leads to compounds of increasing activity, being the more polar hydroxy-substituted derivatives the most active (Table 2) [73]. One of the major obstacles in the development of highly potent drugs is the water solubility. Pettit and co-workers [55] conducted an extensive study in an attempt
- to improve the water solubility of combretastatin D-2 (2) by converting it into a series of phosphate salts and other prodrugs. Thus, phosphorylation of combretastatin D-2 (2) using dibenzyl phosphite gave derivative 183. Further cleavage of the benzyl groups using TMSBr followed by the reaction of
- the obtained phosphoric acid derivative with a series of bases led to the formation of different phosphate salts 184–187 (Scheme 35) [55]. The authors observed that the prodrug salts had substantially improved solubility in water, an important feature for transport to metastatic cancer (Table 3) [75
Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis
Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30
- solubility and bioaccessibility of the hazelnut oil components and antioxidants can be increased, as well as the controlled release of bioactive compounds (fatty acid glycerides and antioxidant flavonoids, namely hesperidin, naringin, rutin, and silymarin). The appropriate method for obtaining the ternary
- , leading to high water solubility. On the other hand, the tetrahydropyran moieties of the Glcp units provide the hydrophobic property of the CD cavity [4]. As a consequence of their unique structure, CDs can encapsulate hydrophobic molecules or hydrophobic moieties of geometrically compatible bioactive
- compounds [5]. The resulting supramolecular inclusion complexes provide enhanced water solubility and bioavailability/bioaccessibility of the nanoencapsulated bioactive compounds, higher oxidative and thermal stability or photostability of labile compounds, and their controlled release [6][7]. Vegetable oil
CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview
Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29
- -base analogues 41a,b were also obtained by the treatment with HCl in dioxane. The conjugation of carbohydrate with porphyrin improves the solubility of porphyrin in aqueous medium and also improves the optical and medicinal properties of porphyrins [30]. Considering these properties of glycoporphyrins
- porphyrin 174 and stirred at room temperature for 24 h, solubilization occurred, resulting in a homogeneous solution. This is due to the formation of a supramolecular assembly in which the hydrophobic adamantane arms of 176b are sequestered by the β-CD arms of porphyrin 174, resulting in water solubility
Synthesis and reactivity of azole-based iodazinium salts
Beilstein J. Org. Chem. 2023, 19, 317–324, doi:10.3762/bjoc.19.27
- , the reaction of 4aa in DCE at 50 °C gave the product 5aa in 23% yield (Table 1, entries 1 and 2). A larger amount of TfOH turned out to increase the solubility of the product and therefore impeded the purification process. However, an excess of acid is required for the electrophilic aromatic
Continuous flow synthesis of 6-monoamino-6-monodeoxy-β-cyclodextrin
Beilstein J. Org. Chem. 2023, 19, 294–302, doi:10.3762/bjoc.19.25
- complexation can lead to a significant solubility enhancement of poorly water-soluble molecules, and therefore it can enable the biological testing of drugs, which would otherwise not be possible by any other means [2][3]. Monosubstituted CDs contain only one hydroxy group modified with a functional group. In
- -toluenesulfonyl)-β-CD (Ts-β-CD, 2) There are three standard methods for the preparation of this general and functional CD derivative. Two of them take advantage of the lower aqueous solubility of β-CD (1) and Ts-β-CD (2) compared to α- and γ-CD analogs. The third method is mainly used for Ts-α-CD and Ts-γ-CD
Investigation of cationic ring-opening polymerization of 2-oxazolines in the “green” solvent dihydrolevoglucosenone
Beilstein J. Org. Chem. 2023, 19, 217–230, doi:10.3762/bjoc.19.21
- biomedical applications, in particular as an alternative to the hydrophilic poly(ethylene glycol) (PEG), which is the polymer of choice for many biomedical applications due to its high solubility, low cytotoxicity and biocompatibility [3][4][5][6][7][8][9]. However, an ongoing discussion about pre-existing
- /or initiator did not yield considerable improvements. It is known that MeOx polymerization can be challenging due to the poor solubility of PMeOx in some solvents [30][31][34]. However, no precipitation was observed during polymerization, which rules out the solubility as an issue. Therefore, we
Sequential hydrozirconation/Pd-catalyzed cross coupling of acyl chlorides towards conjugated (2E,4E)-dienones
Beilstein J. Org. Chem. 2023, 19, 176–185, doi:10.3762/bjoc.19.17
- ). Accordingly, the internal double bond in 25a stayed unaffected whereas the triple bond, as expected, selectively formed the double bond with (E)-configuration. Note that a reaction temperature of 50 °C is required in the first step of the sequence to obtain rapid solubility of the Schwartz reagent in the
Synthesis and characterisation of new antimalarial fluorinated triazolopyrazine compounds
Beilstein J. Org. Chem. 2023, 19, 107–114, doi:10.3762/bjoc.19.11
- improve solubility and metabolic stability while retaining potency [5]. Late-stage functionalisation (LSF) is a strategy involving the use of C–H bonds as chemical handles for the introduction of various functional groups, which has been widely employed by medicinal chemists to generate new analogues of
Catalytic aza-Nazarov cyclization reactions to access α-methylene-γ-lactam heterocycles
Beilstein J. Org. Chem. 2023, 19, 66–77, doi:10.3762/bjoc.19.6
- the reactivity of a thiophene-fused dihydropyridine as a cyclic imine. The tricyclic α-methylene-γ-lactam product 19k was obtained in 40% yield and as single diastereomer. It should be noted that due to the low solubility of the imine substrate in CH3CN, this reaction was carried out in CH2Cl2 at 23
Two-step continuous-flow synthesis of 6-membered cyclic iodonium salts via anodic oxidation
Beilstein J. Org. Chem. 2023, 19, 27–32, doi:10.3762/bjoc.19.2
- further by increasing the charge (Table 2, entry 5). For a final combination of the two reaction steps, benzyl acetate 3a was chosen as a model substrate due to its high solubility and good reactivity as was previously demonstrated by us (Table 3) [28]. We determined an optimal reaction time of 20 min for
Inclusion complexes of the steroid hormones 17β-estradiol and progesterone with β- and γ-cyclodextrin hosts: syntheses, X-ray structures, thermal analyses and API solubility enhancements
Beilstein J. Org. Chem. 2022, 18, 1749–1762, doi:10.3762/bjoc.18.184
- Alexios I. Vicatos Zakiena Hoossen Mino R. Caira Centre for Supramolecular Chemistry Research (CSCR), Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa 10.3762/bjoc.18.184 Abstract Overcoming the challenges of poor aqueous solubility of active pharmaceutical
- ingredients (APIs) is necessary to render them bioavailable. This study addresses the poor solubility of two potent steroid hormones, 17β-estradiol (BES) and progesterone (PRO), via their complexation with two water-soluble native cyclodextrins (CDs) namely β-CD and γ-CD. The hydrated inclusion complexes β
- 1H NMR spectroscopy. Subsequent measurements of the aqueous solubilities of the four complexes confirmed significant solubility improvements effected by encapsulation of the steroids within the CDs, yielding solubility enhancement factors for BES and PRO in the approximate range 5–20. Keywords
Synthesis of (−)-halichonic acid and (−)-halichonic acid B
Beilstein J. Org. Chem. 2022, 18, 1629–1635, doi:10.3762/bjoc.18.174
- reducing agent sodium bis(2-methoxyethoxy)aluminum hydride (Red-Al®), which is a convenient alternative to LiAlH4 that exhibits high solubility in organic solvents and is also known to reduce amides [17]. When a solution of amide 5 in toluene was treated with an excess of Red-Al® at 0 °C, rapid gas
A new route for the synthesis of 1-deazaguanine and 1-deazahypoxanthine
Beilstein J. Org. Chem. 2022, 18, 1617–1624, doi:10.3762/bjoc.18.172
- alcohol. We build on a commercially available imidazopyridine derivative and conceived a protecting group strategy to enhance solubility and selectivity to orchestrate the installation of the exocyclic amino and hydroxy groups. Results and Discussion 1-Deazaguanine Previously described syntheses for 1
- be easily prepared from its commercially available 6-chloro derivative [16]. To enable C–O coupling with benzyl alcohol, protection of the N9 with a tetrahydropyranyl group was necessary due to limited solubility of the aryl iodide. Therefore, 6-iodo-1-deazapurine was treated with tosylic acid and
- the cross coupling reaction. We also mention that we did not decide for a direct transformation [27][28] of 6-iodo-1-deazapurine into 6-hydroxy-1-deazapurine for reasons of solubility and desired regioselectivity of the subsequent nitration reaction. 1-Deazahypoxanthine Synthesis of 1
Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene
Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170
- 1H NMR and NOESY NMR imply the dependence of molecular symmetry on the type of spacer. The ability of synthesized dimers to increase the solubility of tetracene in DMSO was evaluated and compared to native cyclodextrins and their methylated derivatives. The newly synthesized compounds expressed
- substituted rims are partially methylated CDs. Methylation reduces the formation of intramolecular hydrogen bonds, enhancing CDs water solubility, and also extends the hydrophobic cavity, thus improving its binding potential. A substantial increase of binding constant (K) for per-6-methylated CD compared to
- native CD was described, but an order of magnitude decrease of K was found for permethylated CD [2]. Also, methylation changes the solubility of CDs in organic solvents, expanding their potential field of application. CDs form the most stable complexes with hydrophobic compounds in polar solvents such as
Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface
Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156
- diblock copolymer. Binding between the integrin receptor and the RGD peptide on the polymer increased the solubility of the polymer above the associated electrodes and in so doing increased the current associated with the mediator. This change in current relative to the concentration of integrin in
One-pot synthesis of 2-arylated and 2-alkylated benzoxazoles and benzimidazoles based on triphenylbismuth dichloride-promoted desulfurization of thioamides
Beilstein J. Org. Chem. 2022, 18, 1479–1487, doi:10.3762/bjoc.18.155
- furnished the tricyclic compound 8v in 84% yield. In contrast, the reaction with 3-amino-2-anthracenol resulted in a low yield of the tetracyclic compound 8w due to the low solubility of aminoanthracenol. The reaction of 2a with 2-aminothiophenol instead of 2-aminophenol proceeded smoothly, and the
Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides
Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147
- due to the strong electron-withdrawing effect of bromine, enhancing the electrophilic property of bromo-substituted salicylaldehyde. Because of the poor solubility in the eluent, the yield of dichloro-containing 1c (88%) was lower than 1a after isolating by column chromatography. This was also found
On drug discovery against infectious diseases and academic medicinal chemistry contributions
Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141
- , current trends are found in reports from the industry. A paper from Novartis describes that solubility and cell permeability are, for phenotype-based screenings, the favorite criteria along with structural diversity in regard with previously observed biological effects [86]. Along with such parameters, a
Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies
Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140
- various organic molecules have been described so far. It was proved that the complexation of volatile organic compounds, such as aldehydes, into the CD’s cavity reduces the volatility and increases the solubility and bioavailability of these compounds [5][6][7][8][9][10][11][12][13][14]. The release of
- phosphate buffer solutions of pH 1.08, 2.00, 3.00, 4.00, 5.00, 6.00, 7.00, 8.00, 9.00, 10.00 11.00, 12.00, and 12.80 were prepared (see Experimental section) using deuterium oxide instead of water to facilitate NMR spectroscopy experiments. Because of the low solubility of the pro-fragrance in water, it had
- of a pH meter. Because of the poor solubility of the pro-fragrance in water, it had to be dissolved in 0.5 mL of deuterated dimethyl sulfoxide. Then, the buffer solutions (0.5 mL) were added and mixed just before starting the measurements. The samples were kept at ambient temperature (20–25 °C
Make or break: the thermodynamic equilibrium of polyphosphate kinase-catalysed reactions
Beilstein J. Org. Chem. 2022, 18, 1278–1288, doi:10.3762/bjoc.18.134
- soluble enzymes and could be easily purified via Ni-NTA affinity chromatography using N-terminal His-tags, the PPK1 enzymes required an N-terminal maltose binding protein (MBP-tag) to improve solubility [46][47]. Trials to cleave the MBP-tag were unsuccessful and resulted in inactive protein aggregates
Heterogeneous metallaphotoredox catalysis in a continuous-flow packed-bed reactor
Beilstein J. Org. Chem. 2022, 18, 1123–1130, doi:10.3762/bjoc.18.115
- concentration as in the original batch report [28]. This was unlike the C–S coupling, where the limited solubility of the sulfinate salt required a dilution of the reaction conditions to obtain a homogenous reaction mixture. As previously observed [28], the reaction concentration has a significant impact on the
Electrochemical Friedel–Crafts-type amidomethylation of arenes by a novel electrochemical oxidation system using a quasi-divided cell and trialkylammonium tetrafluoroborate
Beilstein J. Org. Chem. 2022, 18, 1040–1046, doi:10.3762/bjoc.18.105
- likely nucleophile in this reaction medium was the trifluoroacetate ion, which was produced by electrochemical reduction of TFA at the cathode, although we could not detect the coupling product of trifluoroacetate and the corresponding N-acyliminium ion due to the high solubility in water. In addition to
- M iPr2NHEtBF4 using a quasi-divided cell gave 3-amidomethylated N-methylindole 9 in 47% 1H NMR yield and 44% isolated yield at full conversion (Scheme 4). The moderate yield of 9 is thought to be due to its high solubility in water. A probable reaction pathway is shown in Scheme 5. The present
First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell
Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98
- recycle them, good stability, low flammability, good solubility ability for many molecules, salts and gases, the possibility to use them as reagents and/or solvents, large electrochemical window, good electrical conductivity, their ionic nature sometimes increases the reactivity and the selectivity of
Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials
Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94
- -withdrawing keto groups. To enable solubility in common organic solvents, the fused system is flanked by ethylhexylthiophene groups. The material is a dark, amorphous solid with an onset of absorption at 638 nm in CH2Cl2 solution, which corresponds to an optical gap of 1.94 eV. In films, the absorption onset
- to poor solubility as a consequence of strong π–π interactions between the planar molecules [4]. Thus, attaching solubilising alkyl chains is necessary [5]. A common way to further decrease the HOMO–LUMO gap is attaching electron-donating and electron-accepting groups. Electron-rich units raise the
- a certain application, for example where charge transport is more important than photoluminescence quantum yield or vice versa. Introducing alkyl chains can provide solubility, enabling facile solution processing, such as device printing techniques [13]. Hence, there is an ongoing interest in
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