The recombinant thioesterase (TE) domain of the picromycin/methymycin synthase (PICS) catalyzes the macrolactonization of 3, the N-acetylcysteamine thioester of seco-10-deoxymethynolide to generate 10-deoxymethynolide (1) with high efficiency. By contrast, 4, the 7-dihydro derivative of seco-thi...

BackgroundA single modular polyketide synthase (PKS) gene cluster is responsible for production of both the 14-membered macrolide antibiotic picromycin and the 12-membered macrolide antibiotic methymycin in Streptomyces Venezuelas. Building on the success of the heterologous expression system en...

In this study we introduce the use of thiol-ene photopolymers as shape memory polymer systems. The thiol-ene polymer networks are compared to a commonly utilized acrylic shape memory polymer and shown to have significantly improved properties for two different thiol-ene based polymer formulation...

Soft poly(thioether) thermosets have been synthesized by employing a two-step curing procedure based on click chemistry. The first stage of curing is a thiol-Michael addition between acrylates (or methacrylates) and thiols in excess, catalyzed by a set of novel tertiary amine catalyst comonomers...

An amorphous co-network consisting of poly(ethylene glycol) diacrylate (PEGDA) and thiosiloxane was prepared by means of thiol-ene “click” reaction to impart high ion conduction via enhanced segmental mobility of the co-network. By varying PEGDA-thiosiloxane ratios, several polymer electrolyte...

The structure of the domains of phase-separated binary self-assembled monolayers (SAMs) composed of 3-mercapto-1-propanol and 1-tetradecanethiol (TDT) on Au(1 1 1) strongly depends on the thiol concentration of the solution from which the SAM is formed. Cyclic voltammograms and scanning tunnelin...

Titanocene or permethylzirconocene dichloride reacts with 1 molar equivalent of 3-mercapto-1-propanol (HOCH2CH2CH2SH) in the presence of NEt3 to give the monomeric chelate complex Cp2Ti(OCH2CH2CH2S) (1) or the oxygen-bonded monomeric complex Cp2∗ZrCl(OCH2CH2CH2SH) (2), respectively. When Cp2∗Zr(...

The lipase-catalyzed chemospecific O-acylation of 3-mercapto-1-propanol and 4-mercapto-1-butanol by several aliphatic carboxylic acid ethyl esters are described. Similar treatment on 1-mercapto-2-propanol and 3-mercapto-2-butanol did not yield the expected O-acyl derivatives.

Racemic as well as enantiomerically pure trans-1,1′-(cyclohexane-1,2-diyl)bis(imidazole N-oxides) were prepared from trans-cyclohexane-1,2-bis(methylidenamine) and 1,2-dione monooximes (α-hydroxyiminoketones). The enantiomeric purity of selected products was determined by means of 1H NMR spect...

During the stability study of Tolterodine tartrate drug product, two unknown impurities (Impurities I and II) were detected by ultra performance liquid chromatography (UPLC). Both impurities were isolated by preparative liquid chromatography and were subjected to mass and NMR spectral studies. B...

A range of N,N-dialkylanilines have been successfully converted to the parent substituted benzenes by a novel two-step pathway. The products are obtained in good yields and optical purity of adjacent stereocenters is maintained. This technology has been applied toward the synthesis of (R)-tolter...

Ladostigil is a pseudo reversible inhibitor of acetylcholinesterase (AChE) that differs from other carbamates in that the maximal enzyme inhibition obtainable does not exceed 50–55%. This could explain the low incidence of cholinergic adverse effects induced by ladostigil in rats and human subj...

The potent β2-adrenergic receptor agonist formoterol (R,R)-1 has been obtained in enantiomerically pure form by a convenient chemoenzymatic approach by coupling of epoxide (R)-6 with the unprotected primary amine (R)-9. Both chiral precursors have been prepared by enantiodifferentiation process...

A spectrometric approach for the sensitive detection of 2,4-dichlorophenoxyacetic acid (2.4-D) was developed based on the inhibitory effect of 2,4-D on the enzymatic activity of catalase. The magnetic Fe3O4-chitosan nanocomposites pre-activated with glutaraldehyde was used as support to improve ...

In this work, a novel molecularly imprinted electrochemical sensor based on the amino-functionalized silica nanoparticles was built for the sensitive and selective detection of 2,4-dichlorophenoxyacetic acid (2,4-D). The hierarchical porous dendrimer-like silica nanoparticles (HPSNs-NH2) were sy...

A method for determining urinary concentrations of 2,4-D in samples collected from non-occupationally, environmentally exposed individuals was developed. The 2,4-D was extracted from fortified human urine samples using octadecylsilane solid phase extraction cartridges. The average percent recove...

Three new silver complexes based on 2,6-dichlorophenylacetate (dcpa), namely [Ag2(dcpa)2]n (1), [Ag(NH3)2](dcpa) (2), and [Ag3(N,N-eten)(dcpa)3]2 (3) (N,N-eten = N,N-diethylethylenediamine), were synthesized and structurally characterized. The dcpa ligand adopts a µ2-η1:η1 bridging coordinati...

A high throughput, low environmental impact methodology for rapid determination of phenoxy carboxylic acids (PCAs) in water samples was developed by combing dispersive solid phase extraction (DSPE) using velvet-like graphitic carbon nitride (V-g-C3N4) and direct analysis in real time mass spectr...

A molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-dichlorophenoxyacetic acid (2,4-D) was prepared by a surface imprinting technique in combination with a sol-gel process. The 2,4-D-imprinted amino-functionalized silica sorbent was characterized by FT-IR, nitrogen ...

General method for preparation of high yields of novel N-protected carborane amino acid derivatives, 3-acylamino-1-carboxymethyl-2-R-o-carboranes (R = H, Me, Ph), is reported. The synthesis starts from readily available 3-amino-o-carboranes and includes the protection of amino group, introductio...