Alcohol Derivatives Research Articles

Construction of Axially Chiral 4-Aminoquinolines by Cycloaddition and Central-to-Axial Chirality Conversion.

A two-step strategy has been established for the enantioselective synthesis of 4-aminoquinolines possessing axial chirality. This approach involves a chiral phosphoric acid-catalyzed cycloaddition, followed by a DDQ oxidation step. The method offers efficient access to a variety of 1,1'-biaryl-2,2'-amino alcohol derivatives in excellent yields and enantioselectivities (up to 98% yield and 93% ee). Furthermore, the synthetic transformation of the products was also investigated.

Silylation of Nitrogen-Containing Compounds Using Trimethylsilylimidazole in the Active Medium of Hexamethyldisilazane

A new silylating system is suggested based on trimethylsilylimidazole in the active medium of hexamethyldisilazane, which allows for the introduction of trimethylsilyl units both at the OH and NH2 groups. The use of this system ensures the synthesis of trimethylsilyl derivatives of amino alcohols in one stage, and, in the case of aniline and N,N-dimethylhydrazine, significantly reduces the reaction time and increases the product yields.

Synthesis of β-lactams and transformation to β-amino acid ethyl ester derivatives: Theoretical calculations

Because of the important biological properties of β-amino acids in the present work, two new β-amino acid ethyl ester derivatives were synthesized, and their mechanistic occurrence was investigated. The title compounds were synthesized from related tetralone derivatives containing bromine and methoxy groups. Tetralone derivatives were reduced to their benzyl alcohol derivatives with NaBH4, followed by elimination with p-toluenesulfonic acid (pTSA) to give the desired 1,2-dihydronaphthalene derivatives. The reactions of 1,2-dihydronaphthalenes with chlorosulfonyl isocyanate (CSI) afforded β-lactams. β-Amino acids were obtained from the reaction of β-lactams with EtOH in HCl. Computational studies are concerned with synthesizing four-membered lactams (β-lactam) formed by the reaction between 1,2-dihydronaphthalene derivatives and CSI. The mechanism of the formation of compounds has been elucidated using DFT at M06-2X.

Structural Characterization and Anti-inflammatory Activities of a Purified Polysaccharide from Veronica persica Poir.

In this manuscript, the polysaccharide (VPP-I) from Veronica persica Poir., was characterized in detail by high performance gel permeation chromatography (HPGPC), high performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). In addition, lipopolysaccharide (LPS) induced inflammation model of RAW264.7 cells was used to evaluate the in vitro anti-inflammatory activity of VPP-I. The results showed that the relative molecular weight of VPP-I was 2.355 KDa, which was mainly composed of mannose (Man), glucose (Glc) and galactose (Gal) in a ratio of 1 : 32.46 : 28.76. Moreover, the VPP-I contained sugar alcohol derivatives of T-DGlcp(1→, →4)-D-Galp(1→, →3,6)-D-Manp(1→, →4)-D-Glcp(1→, →6)-D-Galp(1→ and →6)-D-Glcp(1→. In vitro anti-inflammatory results showed that VPP-I could inhibit the secretion of IL-β, IL-6 and TNF-α in RAW264.7 cells induced by LPS. Moreover, compared to the LPS group, the mRNA expression levels of iNOS, COX-2, IL-β, IL-6 and TNF-α produced by RAW264.7 were significantly decreased after treatment with VPP-I (P<0.05). In addition, VPP-I could increase the SOD and GSH-Px enzymes activity and decrease the content of MDA in LPS-induced RAW264.7 cells (P<0.05). In summary, this paper laid theoretical foundation for the application of Veronica persica Poir. in the field of medicine.

Cell Dome-based transfection array for non-adherent suspension cells

Cell-based microarrays are valuable tools for analyzing cellular functions. However, a significant limitation of conventional microarrays is their inapplicability to non-adherent cells. In this study, we investigated the potential of the ‘Cell Dome’ (diameter: 1 mm, height: approximately 300 µm) with a 90 µm-thick hydrogel shell as a gene transfection array for non-adherent cells in suspension. The human lymphoma cell line (K562 cells), used as a model for non-adherent cells, was transfected more efficiently by Lipofectamine/pDNA complexes on a composite hydrogel made of polyvinyl alcohol derivative (PVA-Ph) and chitosan derivative (chitosan-Ph) than hydrogels composed of an alginate derivative or PVA-Ph alone. Moreover, no significant adverse effects on the viability and proliferation of the enclosed cells were observed for Cell Dome with a PVA-Ph/chitosan-Ph composite hydrogel shell. Lipofectamine/pDNA complexes released from the bottom of Cell Domes could transfect the enclosed cells without leaking or contaminating adjacent Cell Domes. These results demonstrate the potential of Cell Domes with an appropriate hydrogel shell as transfection arrays for non-adherent cells in suspension, thereby expanding the range of applications of cell-based array technologies. This novel Cell-Dome transfection array would be a valuable tool for analyzing the cellular function of non-adherent cells in suspension and showcases the potential for providing important biomedical insights for future research and developments.

Thiazolidine-4-one Analogues: Synthesis, In-Silico Molecular Modeling, and In-vivo Estimation for Anticonvulsant Potential.

Epilepsy is a critically deep-rooted CNS disorder affecting above 50 million people all over the world. Thus, a safe and effective treatment that proves its worth in this ailment is urgently needed. Thiazolidine-4-ones possess the molecules to be used as anticonvulsants. The thiazolidinedione is a cyclic analogue of thiosemicarbazides and thioureas as well as a (bio)isostere of hydantoin (imidazolidine-2,4-dione), which are recognized as novel anticonvulsant designs. This study aimed to develop and evaluate a novel thiazolidine-4-one derivative by three-component condensation in one pot reaction method. A novel thiazolidine-4-one derivative was formulated by three-component condensation. The selected OH (Alcohol) derivatives were found to be more potent; hence, a molecular docking study against a selected target LGI1 LRR domain was performed. Various analytical tests like FTIR and H1 NMR were accomplished. The FTIR was used to validate the existence of multiple functional moieties like C-S, O-H, C=O, C-N, N=O, C-NH, C-O in the wave region from 3075 cm-1 - 1236 cm-1 and H1 NMR was employed to ascertain if the synthesized analogues had the complete set of protons. Then, the anti-seizure activity of the selected compound was examined using PTZ models in mice at three successive doses, i.e., 25, 50, and 100mg/kg, and compared with standard ethosuximide. The docking simulations were initiated using PyMOL after the binding site was determined and the receptor and ligand were suitably prepared. It showed higher binding frequency in comparison to the standard marketed drug Ethosuximide. FTIR and H1 NMR spectroscopy were used to characterize the chemical components. Numerous functional groups, including O-H (alcohol), C=O (ketones), N=O, C-NH, C-N, C-S, and C-O bending stretching, were visible in the synthesized molecule accordingly. The synthesized compound was effective in inhibiting the convulsions at the concentration of 100 mg/kg. The novel thiazolidine-4-one derivative showed promising activity and could be considered for further investigation and dosage form preparation.

Nickel-Catalyzed Asymmetric (3 + 2) Annulations of Propargylic Carbonates and Vinylogous Donors via an Alkenylation Pathway.

The transition-metal-catalyzed alkenylation strategy of propargylic alcohol derivatives provides an efficient protocol to access multifunctional products in a double-nucleophilic attack pattern. While limited relevant asymmetric examples have been reported via palladium catalysis, here we first demonstrate that a nonprecious Ni(0)-based chiral complex can efficiently promote the tandem substitution process between propargylic carbonates and N-trifluoroethyl ketimines via consecutive aza-vinylogous activations, finally accomplishing a (3 + 2) annulation reaction to afford products embedding a 4-methylene-3,4-dihydro-2H-pyrrole framework with high regio-, diastereo-, and enantiocontrol. Their assemblies with a few all-carbon-based vinylogous precursors are also successful, and enantioenriched adducts containing a 3-methylenecyclopentene scaffold are furnished effectively. The substitution patterns for both types of substrates are substantial, and an array of synthetic elaborations is conducted to deliver more versatile architectures with high application potential. In addition, density functional theory calculations and control experiments have been conducted to rationalize the catalytic pathways and regio- and enantioselectivity control.

Selective and fast oxidation of alcohol to aldehyde using novel catalytic deep eutectic solvent surfactants.

Deep eutectic solvent (DES) has been considered as a useful catalyst and reaction medium for various organic transformations. Herein, we report the catalytic application of novel deep eutectic solvent- based surfactant (DES surfactant) for the selective and fast oxidation of alcohols to aldehydes. The readily accessible DES surfactants (FeCl3/BHDC) was prepared using inexpensive ferric chloride (FeCl3) and benzyl hexadecyl dimethyl ammonium chloride in a simple manner. The synthesized FeCl3/BHDC was characterized using various techniques, including, FTIR spectroscopy, thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and energy- dispersive X-ray spectroscopy (EDS) to determine its structure. The catalytic activity of FeCl3/BHDC in the selective oxidation of various alcohols to corresponding aldehyde derivative was investigated. The results showed the reaction could be completed within very short reaction times ranging from 2 to 15min, while achieving good to excellent yields. This protocol offers a facile strategy and excellent efficiency in selectively oxidizing various alcohol derivatives to their respective aldehydes and ketones, utilizing hydrogen peroxide in the presence of catalytic DES surfactant.

Association of tobacco and alcohol consumption with hypertension among Hindu priests in Central India

Background: Alcohol and tobacco use are among the major risk factors for causing hypertension in the adult population globally as well as in India. India being a religious country harbor’s large number of Hindu temples which are conventionally managed by a dedicated population of Hindu priests. The prevalence of alcohol and tobacco use in this special population of priests in India is not well established along with the associated risk of hypertension. Aims and Objectives: First, to study the pattern of use of habit-forming substances; tobacco, alcohol, and cannabis derivatives among priests in central India. Second, to find the relationship between the use of tobacco smoking, chewing, and alcohol with hypertension. Materials and Methods: The current study is a cross-sectional survey on Hindu priests of registered temples of a Pilgrimage city in Central India. The study utilizes a pre-tested semi-structured questionnaire for interviewing 440 study participants. It included a sociodemographic profile, history of use of habit-forming substances, the presence of known hypertension, and measurement of blood pressure. Results: Out of 440 study participants; 280 (63.6%) were currently using habit-forming substances, whereas 160 (36.4%) number of participants had never used it. The current study found the prevalence of hypertension to be 31.9%. A statistically significant relationship of hypertension with the use of alcohol (χ2=44.2), tobacco chewing (χ2=106.1), and smoking (χ2=74.3) was found. Conclusion: The current study concludes that the use of Habit-forming substances, especially alcohol, tobacco chewing, and smoking, are prevalent among priests which are known risk factors for hypertension in the general population. Hence all screening/interventions applicable for these risk factors should be applied to this special population of priests.

Pickering Emulsion Promoted Interfacial Sequential Chemo-Biocatalytic Reaction for the Synthesis of Chiral Alcohols from Styrene.

Chemo-biocatalytic cascades have emerged as a promising approach in the realm of advanced synthesis. However, reconciling the incompatible reaction conditions among distinct catalytic species presents a significant challenge. Herein, we introduce an innovative solution using an emulsion system stabilized by Janus silica nanoparticles, which serve as a bridge for both chemo-catalysts and biocatalysts at the interface. The chemo-catalyst is securely anchored within a hydrophobic polymer matrix, ensuring its residence in an organic environment. Meanwhile, the negatively charged E. coli cells containing enzymes are attracted to the aqueous phase at the interface, facilitating their optimal positioning. We demonstrate the efficacy of this system through a two-step cascade reaction. Initially, the oxidation of styrene to acetophenone using palladium as a chemocatalyst achieves a 6-fold increase in yield compared to the control system. Subsequently, the reduction of achiral acetophenone to its chiral alcohol derivative presents a 17-fold yield enhancement relative to that of the control reaction. Importantly, our system exhibits versatility, accommodating a wide range of substrates for both individual and sequential reactions. This work not only validates the concept but also paves the way for the integration of chemo- and biocatalysts in the synthesis of a broader array of high-value chemical compounds.

Synthetic Methods and Pharmacological Potentials of Isothiocyanate Derivatives

The present review deals with different synthetic methods of isothiocyanates, including alcohols, aryl chlorides, primary amines, carboxylic acid or carboxylic acid derivatives, cleavage of heterocyclic compounds, and alkene derivatives as a starting material. Furthermore, the thermal rearrangement of thiocyanate, decomposition of thiourea derivatives, and natural isothiocyanates are discussed. It also includes the chemical reaction of isothiocyanates derivatives, such as reaction with alkenes and aromatic compounds, addition of water and amine derivatives, reaction with amino alcohol derivatives, reaction with amino acids and their derivatives, reaction with hydrazine and acid hydrazide derivatives, and miscellaneous reactions. In addition, this review summarizes different pharmaceutical applications of isothiocyanate derivatives, such as anticancer, antimicrobial, antioxidant, and anti-inflammatory activities.

TMSCN-Promoted Difunctionalization of Alkenes for the Synthesis of Alcohol Derivatives.

A TMSCN-promoted difunctionalization of styrenes with CHCl3 and TBHP is reported via the radical addition/cross coupling process. A wide range of dichloromethyl-substituted alcohol derivatives were synthesized under transition-metal-free conditions. Besides, this method is also applicable to unactive alkenes. The key to this success lies in the role of TMSCN, which prevents the reaction toward dichloromethylperoxylation of olefins. This represents an alternative approach for synthesizing diverse alcohol derivatives using readily available substrates, holding significant promise in the fields of pharmaceutical chemistry and natural product synthesis.

Pd(0)/Xantphos-Catalyzed Benzylic C(sp3)-O Arylation of Benzyl Heteroaryl Ethers: Reduction of Pd(II) to Pd(0) by Xantphos.

Herein, we report the synthesis of 1,1-diarylmethanes via palladium-catalyzed benzylic C(sp3)-O arylation of benzyl alcohol derivatives. An efficient, straightforward approach to synthesizing Pd(0)(xantphos)2 was developed through in situ reduction of Pd(II) to Pd(0) with the bidentate tertiary phosphine xantphos, which proved to be a highly active precatalyst in the Suzuki-Miyaura cross-coupling reaction of benzyl heteroaryl ethers.

The utility of Streptococcus mutans undecaprenol kinase for the chemoenzymatic synthesis of diverse non-natural isoprenoids

Isoprene chemoenzymatic cascades (ICCs) overcome the complexity of natural pathways by leveraging a streamlined two-enzyme cascade, facilitating efficient synthesis of C5-isoprene diphosphate precursors from readily available alcohol derivatives. Despite the documented promiscuity of enzymes in ICCs, exploration of their potential for accessing novel compounds remains limited, and existing methods require additional enzymes for generating longer-chain diphosphates. In this study, we present the utility of Streptococcus mutans undecaprenol kinase (SmUdpK) for the chemoenzymatic synthesis of diverse non-natural isoprenoids. Using a library of 50 synthetic alcohols, we demonstrate that SmUdpK’s promiscuity extends to allylic chains as small as four carbons and benzylic alcohols with various substituents. Subsequently, SmUdpK is utilized in an ICC with isopentenyl phosphate kinase and aromatic prenyltransferase to generate multiple non-natural isoprenoids. This work provides evidence that, with proper optimization, SmUdpK can act as the first enzyme in these ICCs, enhancing access to both valuable and novel compounds.

Directing Group Guided Site−Selective Alkylation of Indoles by Epoxides: Synthesis of β‐Indolylethyl Alcohol Derivatives

A Palladium catalyzed C4‐ alkylation of indoles using epoxide as an alkylating agent and pivaloyl as a weak chelating group has been demonstrated. A variety of substituted epoxides and indoles furnished the desired β‐indolylethylalcohols in 38% ‐ 87% yields. Control experiments indicate that the C−H cleavage step is irreversible. The resultant hydroxyl group has been converted to various functional groups to demonstrate the synthetic utility of this protocol.

Metal‐Free Ammonia Borane‐Catalyzed Hydroboration of Lactones and Esters to Alcohols

AbstractHerein we describe an efficient methodology for metal‐free hydroborative cleavage of lactones and esters with HBPin (Pin=pinacol) to the corresponding alcohol derivatives using ammonia borane as a pre‐catalyst. The reactions proceed under mild conditions, can be performed in a solvent‐free manner, and do not require an inert atmosphere. Combined experimental and computational mechanistic studies suggest a novel mechanism that involves μ‐aminodiboranes as catalytically active species.

Designing Cobalt(II) Complex for Chemoselective Synthesis of 2-Aryl-3-Formyl Indoles from Amino Alcohols and Alcohols†.

An air-stable, inexpensive, and isolable cobalt(II) complex (C1) of N-((1-methyl-1H-imidazol-2-yl)methyl)-2-(phenylselanyl)ethan amine (L1) was synthesized and characterized. The complex was used to catalyze a one-pot cascade reaction between 2-(2-aminophenyl)ethanols and benzyl alcohol derivatives. Interestingly, 2-aryl-3-formylindole derivatives were formed instead of N-alkylated or C-3 alkylated indoles. A broad substrate scope can be activated using this protocol with only 5.0 mol % catalyst loading to achieve up to 87 % yield of 2-aryl-3-formylindole derivatives. The mechanistic studies suggested that the reaction proceeds through tandem imine formation followed by cyclization.

Development of an Easy-To-Handle Redox Active Group for Alcohols: Catalytic Transformation of Tertiary Alcohols to Nitriles.

The generation of radical intermediates via SET-mediated deoxygenation of activated alcohol derivatives is desirable, as alcohols can be utilized in various radical-mediated reactions. Herein, we introduce α-N-phthalimido-oxy isobutyrate (NPIB) as a novel activating group for alcohols. Essentially, it is a more chemically robust alternative to Overman's N-phthalimidoyl oxalate group. The utility of the NPIB group is showcased in the conversion of tertiary alcohols to nitriles under Ir/Cu dual catalysts and in the presence of TMSCN upon blue LED irradiation. With our newly developed NPIB handle, the reactivities of N-hydroxyphthalimide esters derived from carboxylic acids would be achievable with naturally and commercially more abundant alcohol substrates.

Polygonal mesopores microflower catalysts for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene to 2-nitro-4-methylsulfonylbenzoic acid in a continuous-flow microreactor

The development of efficient systems for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene (NMST) to 2-nitro-4-methylsulfonyl benzoic acid (NMSBA) with atmospheric air or molecular oxygen in alkaline medium presents a significant challenge for the chemical industry. Here, we report the synthesis of FeOOH/Fe3O4/MOF polygonal mesopores microflower templated from a MIL-88B(Fe) at room temperature, which exposes polygonal mesopores with atomistic edge steps and lattice defects. The obtained FeOOH/Fe3O4/MOF catalyst was adsorbed onto glass beads and then introduced into the microchannel reactor. In the alkaline environment, oxygen was used as oxidant to catalyze the oxidation of NMST to NMSBA, showing impressive performance. This sustainable system utilizes oxygen as a clean oxidant in an inexpensive and environmentally friendly NaOH/methanol mixture. The position and type of substituent critically affect the products. Additionally, this sustainable protocol enabled gram-scale preparation of carboxylic acid and benzyl alcohol derivatives with high chemoselectivities. Finally, the reactions can be conducted in a pressure reactor, which can conserve oxygen and prevent solvent loss. Moreover, compared with the traditional batch reactor, the self-built microchannel reactor can accelerate the reaction rate, shorten the reaction time and enhance the selectivity of catalytic oxidation reactions. This approach contributes to environmental protection and holds potential for industrial applications.

Circularly Polarized Room Temperature Phosphorescence through Twisting‐Induced Helical Structures from Polyvinyl Alcohol‐Based Fibers Containing Hydrogen‐Bonded Dyes

AbstractRoom temperature phosphorescence (RTP) materials have garnered significant attention owing to its distinctive optical characteristics and broad range of potential applications. However, the challenge remains in producing RTP materials with more simplicity, versatility, and practicality on a large scale, particularly in achieving chiral signals within a single system. Herein, we show that a straightforward and effective combination of wet spinning and twisting technique enables continuously fabricating RTP fibers with twisting‐induced helical chirality. By leveraging the hydrogen bonding interactions between polyvinyl alcohol (PVA) and quinoline derivatives, along with the rigid microenvironment provided by PVA chains, typically, Q‐NH2@PVA fiber demonstrates outstanding phosphorescent characteristics with RTP lifetime of 1.08 s and phosphorescence quantum yield of 24.6 %, and the improved tensile strength being 1.7 times than pure PVA fiber (172±5.82 vs 100±5.65 MPa). Impressively, the transformation from RTP to circularly polarized room temperature phosphorescence (CP‐RTP) is readily achieved by imparting left‐ or right‐hand helical structure through simply twisting, enabling large‐scale production of chiral Q‐NH2@PVA fiber with dissymmetry factor of 10−2. Besides, an array of displays and encryption patterns are crafted by weaving or seaming to exemplify the promising applications of these PVA‐based fibers with outstanding adaptivity in cutting‐edge anti‐counterfeiting technology.