Transient Boronate Ester Mask Enables a Streamlined First Total Synthesis of Isoacteoside.

The first total synthesis of phenylpropanoid glycoside (PhG) isoacteoside 1 is presented. The synthesis employs a novel protection-free strategy leveraging phenylboronic acid as a transient masking agent to enable regioselective mono-rhamnosylation and caffeoylation. This method circumvents the need for traditional multi-step protection and deprotection steps and enhances overall efficiency and yield.

Concise first total synthesis of phenylethanoid glycosides parvifloroside A and crassifolioside.

The first total synthesis of phenylethanoid glycosides parvifloroside A 1 and crassifolioside 2 is disclosed, achieving excellent 31 % and 33 % overall yield, respectively. The synthesis exploited the inherent reactivity differences among the free hydroxyl groups on 4-O-caffeoyl glucopyranoside 3 intermediate, enabling regioselective caffeoylation and rhamnosylation. The key to the synthesis is using chiral 4-pyrrolidinopyridine organocatalyst 6 to achieve the regioselective caffeoylation and migration of acyl groups.

Concise Total Synthesis of Phenylethanoid Glycoside Acteoside.

Acteoside is a prominent phenylethanoid glycoside (PhG) with diverse pharmacological activities. However, its chemical synthesis has been challenging due to the reliance on extensive protection/deprotection strategies, leading to lengthy routes and low overall yields. Herein, we present a streamlined and efficient synthetic approach that minimizes synthetic complexity while improving overall efficiency.

Exclusive Solvent-Controlled Regioselective Catalytic Synthesis of Potentially Bioactive Imidazolidineiminodithiones: NMR Analysis, Computational Studies and X-ray Crystal Structures.

Herein, we describe the first consistent regiospecific reaction of isothiocyanates with a variety of substituted -arylcyanothioformamides in a 1:1 molar ratio to generate a series of imidazolidineiminodithiones decorated with a multitude of functional groups on both aromatic rings. The reaction is carried out at room temperature using a 20 mol% catalytic amount of triethylamine with DMF as the solvent to selectively form the mentioned products with exclusive regioselectivity. The methodology features wide substrate scope, no requirement for chromatography, and good to high reaction yields.

First X-ray Crystal Structure Characterization, Computational Studies, and Improved Synthetic Route to the Bioactive 5-Arylimino-1,3,4-thiadiazole Derivatives.

-arylcyanothioformamides are useful coupling components for building key chemical intermediates and biologically active molecules in an expedited and efficient manner. Similarly, substituted ()-2-oxo--phenylpropanehydrazonoyl chlorides have been utilized in numerous one-step heteroannulation reactions to assemble the structural core of several different types of heterocyclic compounds. Herein, we demonstrate the effectiveness of the reaction of -arylcyanothioformamides with various substituted ()-2-oxo--phenylpropanehydrazonoyl chlorides to produce, stereoselectively and regioselectively, a range of 5-arylimino-1,3,4-thiadiazole derivatives decorated with a multitude of functional groups on both aromatic rings.

A Concise Synthesis of Pyrrole-Based Drug Candidates from α-Hydroxyketones, 3-Oxobutanenitrile, and Anilines.

A simple and concise three-component synthesis of a key pyrrole framework was developed from the reaction between α-hydroxyketones, oxoacetonitriles, and anilines. The synthesis was used to obtain several pyrrole-based drug candidates, including COX-2 selective NSAID, antituberculosis lead candidates BM212, BM521, and BM533, as well as several analogues. This route has potential to obtain diverse libraries of these pyrrole candidates in a concise manner to develop optimum lead compounds.

Selective One-Pot Cascade Synthesis of N-Substituted Highly Functionalized Pyrroles from Unprotected Sugars, Primary Amines, and Oxoacetonitriles.

A one-pot, three-component cascade reaction between unprotected sugars, primary amines, and 3-oxoacetonitriles gave N-substituted 2,3,5-functionalized pyrroles or N-substituted 2,3,4-functionalized pyrroles in excellent yields and selectivities. The selectivity of the reaction was achieved by simple control of the sequence of substrate addition. The reaction showed a wide substrate scope, and various types of sugars, primary amines, and oxoacetonitriles reacted smoothly.

Selective One-Pot Multicomponent Synthesis of -Substituted 2,3,5-Functionalized 3-Cyanopyrroles via the Reaction between α-Hydroxyketones, Oxoacetonitriles, and Primary Amines.

A one-step, three-component reaction between α-hydroxyketones, oxoacetonitriles, and primary amines gives -substituted 2,3,5-functionalized 3-cyanopyrroles with complete selectivity in up to 90% isolated yields. The reaction worked on a wide substrate scope under mild reaction conditions (AcOH as a catalyst, EtOH, 70 °C, 3 h). The reaction proceeded with very high atom efficiency as water is the only molecule lost during the reaction.

Chemistry of trisindolines: natural occurrence, synthesis and bioactivity.

Heterocyclic nitrogen compounds are privileged structures with many applications in the pharmaceutical and nutraceutical industries since they possess wide bioactivities. Trisindolines are heterocyclic nitrogen compounds consisting of an isatin core bearing two indole moieties. Trisindolines have been synthesized by reacting isatins with indoles using various routes and the yield greatly depends on the catalyst used, reaction conditions, and the substituents on both the isatin and indole moieties.

Iodine-DMSO mediated conversion of -arylcyanothioformamides to -arylcyanoformamides and the unexpected formation of 2-cyanobenzothiazoles.

Cyanoformamides are ubiquitous as useful components for assembling key intermediates and bioactive molecules. The development of an efficient and simple approach to this motif is a challenge. Herein, we demonstrate the effectiveness of the I-DMSO oxidative system in the preparation of -arylcyanoformamides from -arylcyanothioformamides.

Synthesis, α-glucosidase inhibition, α-amylase inhibition, and molecular docking studies of 3,3-di(indolyl)indolin-2-ones.

The synthesized 3,3-di(indolyl)indolin-2-ones - showed desired higher α-glucosidase inhibitory activities and lower α-amylase inhibitory activities than standard drug acarbose. Particularly, compound showed favorable higher α-glucosidase % inhibition of 67 ± 13 and lower α-amylase % inhibition of 51 ± 4 in comparison to acarbose with % inhibition activities of 19 ± 5 and 90 ± 2, respectively. Docking studies of selected 3,3-di(indolyl)indolin-2-ones revealed key interactions with the active sites of both α-glucosidase and α-amylase, further supporting the observed % inhibitory activities.

Targeted Synthesis of 3,3'-, 3,4'- and 3,6'-Phenylpropanoid Sucrose Esters.

In this study, we report on an orthogonal strategy for the precise synthesis of 3,3'-, 3,4'-, and 3,6'-phenylpropanoid sucrose esters (PSEs). The strategy relies on carefully selected protecting groups and deprotecting agents, taking into consideration the reactivity of the four free hydroxyl groups of the key starting material: di-isopropylidene sucrose . The synthetic strategy is general, and potentially applies to the preparation of many natural and unnatural PSEs, especially those substituted at 3-, 3'-, 4'- and 6'-positions of PSEs.

A Practical Synthesis of Densely Functionalized Pyrroles via a Three-Component Cascade Reaction between Carbohydrates, Oxoacetonitriles, and Ammonium Acetate.

A practical three-component reaction between unactivated carbohydrates, oxoacetonitriles, and ammonium acetate gave densely functionalized pyrroles in 75-96% yields. Disaccharides afforded novel pyrrolo-glycosides. This metal-free, EtN-catalyzed cascade reaction proceeded with exclusive chemo-, regio-, and stereoselectivities and showed a wide substrate scope with high atom economy.

TMSOTf-Promoted Intermolecular Cascade Reaction of Aromatic Diazo Ketones with Olefins: Selective Synthesis of 3-Arylethylideneoxindoles.

A simple trimethylsilyl trifluoromethanesulfonate (TMSOTf)-promoted intermolecular cascade reaction of aromatic diazo ketones with olefins has been developed. This method directly gave 3-phenylethylideneoxindoles from 3-diazooxindoles and styrenes with exclusive regioselectivity, chemoselectivity, and E-stereoselectivity. The key to the success of the reaction and higher yields is the elegant use of TMSOTf, which gradually released the active triflic acid promoter .

Polymer-supported triphenylphosphine: application in organic synthesis and organometallic reactions.

This comprehensive review highlights the diverse chemistry and applications of polymer-supported triphenylphosphine (PS-TPP) in organic synthesis since its inception. Specifically, the review describes applications of the preceding reagent in functional group interconversions, heterocycle synthesis, metal complexes and their application in synthesis, and total synthesis of natural products. Many examples are provided from the literature to show the scope and selectivity (regio, stereo, and chemo) in these transformations.

Perfluorophenylboronic acid-catalyzed direct α-stereoselective synthesis of 2-deoxygalactosides from deactivated peracetylated d-galactal.

Perfluorophenylboronic acid 1c catalyzes the direct stereoselective addition of alcohol nucleophiles to deactivated peracetylated d-galactal to give 2-deoxygalactosides in 55-88% yield with complete α-selectivity. The unprecedented results reported here also enable the synthesis of disaccharides containing the 2-deoxygalactose moiety directly from the deactivated peracetylated d-galactal. This convenient and metal-free glycosylation method works well with a wide range of alcohol nucleophiles as acceptors and tolerates a range of functional groups without the formation of the Ferrier byproduct and without the need for a large excess of nucleophiles or additives.

Robust perfluorophenylboronic acid-catalyzed stereoselective synthesis of 2,3-unsaturated -, -, - and -linked glycosides.

A convenient protocol was developed for the synthesis of 2,3-unsaturated , - and -linked glycosides (enosides) using 20 mol % perflurophenylboronic acid catalyst via Ferrier rearrangement. Using this protocol, D-glucals and L-rhamnals reacted with various , - and -nucleophiles to give a wide range of glycosides in up to 98% yields with mainly α-anomeric selectivity. The perflurophenylboronic acid successfully catalyzed a wide range of substrates (both glucals and nucleophiles) under very mild reaction conditions.

Impact of the type of emulsifier on the physicochemical characteristics of the prepared fish oil-loaded microcapsules.

Fish oil microcapsules were successfully prepared from fish oil-in-water emulsions using chitosan as shell material and anionic surfactants sodium dodecyl sulphate (SDS), sodium dodecylbenzenesulfonate (SDBS), sodium cholate (cholate), and sodium deoxycholate (DOC) as emulsifiers. The type of emulsifier influenced the physicochemical characteristics of the prepared microcapsules to different extents. The microcapsules formed with DOC showed the least mean effective diameter (MED) of 500 nm.

Total synthesis of phenylpropanoid glycoside osmanthuside-B facilitated by double isomerisation of glucose-rhamnose orthoesters.

A convenient synthesis of phenylpropanoid glycoside osmanthuside-B is disclosed. The key steps involved regioselective coumaroylation and rhamnosylation of unprotected phenylethyl-β-d-glucopyranoside to give 2- and 3-O-rhamnosyl orthoester glucopyranosides. Rearrangement of these orthoesters followed by selective removal of their acetyl and allyl groups gave osmanthuside-B in 22% overall yield.

Short synthesis of phenylpropanoid glycoside grayanoside-A and analogues.

A short synthesis of phenylethyl glycosides grayanoside-A 1, 2 and analogues 3-4 in high 43-65% overall yields is described. The main synthetic step involved regioselective O-6 acylation of unprotected 2-phenylethyl-β-D-glucoside 7 with cinnamoyl chlorides 8a-d using MeSnCl as catalyst. The acylation at O-6 is regioselective regardless of the type of cinnamoyl chloride used.

Encapsulation of fish oil with N-stearoyl O-butylglyceryl chitosan using membrane and ultrasonic emulsification processes.

Fish oil-loaded microcapsules were prepared from oil-in-water emulsions using N-stearoyl O-butylglyceryl chitosan as shell material. The emulsions were prepared by both membrane and ultrasonic emulsification processes under variable conditions to examine the effect of the emulsification process and encapsulation conditions on the characteristics of the microcapsules. The microcapsules were characterized with respect to their morphologies, colloidal stability, loading capacity, encapsulation efficiency and release profile.

Synthesis, characterization and the antimicrobial activity of new eco-friendly ionic liquids.

A green microwave-assisted procedure for the preparation of a series of 24 new 1-alkyl-3-ethylimidazolium ionic liquids with different functional groups in the alkyl chain is described. Moreover, the synthesis of a variety of ten new geminal dicationic ionic liquids is reported. Their structures were characterized by FT-IR, (1)H NMR, (13)C NMR, (11)B, (19)F, (31)P, and mass spectrometry.

Synthesis and antiproliferative activity of helonioside A, 3',4',6'-tri-O-feruloylsucrose, lapathoside C and their analogs.

The first total synthesis of natural phenylpropanoid sucrose esters (PSEs) helonioside A 1, 3',4',6'-tri-O-feruloylsucrose 2 and lapathoside C 3 along with 17 unnatural PSE analogs has been successfully accomplished in a short and simple synthetic route. A selected set of 17 synthesized PSEs were evaluated for the antiproliferative activity against human cervical epithelioid carcinoma (HeLa) cell lines using MTS assay method. Eleven (11) compounds showed significant antiproliferative activity with their IC(50)values ranging from 0.

Synthesis and antitumor activity of lapathoside D and its analogs.

Phenylpropanoid sucrose esters are important class of plant-derived natural products and have greater potential to be leads for new drugs because of their structural diversity and broad-array of pharmacological and biological activities. Regio- and chemo-selective acylation of 2,1':4,6-O-di-isopropylidene sucrose 4 with cinnamoyl chloride 5 and p-acetoxycinnamoyl chloride 6 afforded mono-, di-, tri- and tetra- variant PSEs in moderate yields. The first total synthesis of di-substituted PSE, lapathoside D 1' has been achieved successfully in short and simple synthetic steps from sucrose 3 as an inexpensive starting material.