A simple and effective synthesis of enantiomerically pure 2-(N-aryl-, N-alkyl-aminomethyl)aziridines from (2S)-N-tritylaziridine-2-carboxylic acid methyl ester has been developed. Treating of this key ester with several primary and secondary amines in the presence of AlMe3 provided the correspon...

Catechol esters of ortho-methoxyalkylphenylboronic acids have been synthesized and characterized by 17O NMR spectroscopy. The results were compared with the data for the parent acids. The influence of intramolecular and intermolecular hydrogen bonds on the properties of the boronic acids has bee...

Syntheses of Boc-protected 4-amino- and 5-amino-pyrrole-2-carboxylic acid methyl esters have been achieved and the structures of these compounds have been fully characterized by detailed NMR studies.

A novel method for synthesis of 2-butyl-5-chloro-3H-imidazole-4-carbaldehyde 2, a key intermediate of Losartan was reported. The compound 2 was synthesized from starting material dimethyl malonate 6 and n-valeronitrile 8 by six steps with an overall yield of 40%. The key step including the react...

Fiftyeight prochiral ketones have been used inenantioselective hydrosilylation with diphenylsilane promoted by in-situ catalysts consisting of [Rh(cod)Cl]2 and the chiral ligands (4S-2-methyl-2-(2-pyridyl)-4-carbomethoxy-1,3-thiazolidine (A) and (4S)-2-(2-pyridyl)-4-carbethoxy-1,3-thiazolidine (...

A new class of cobalt complexes with optically active N,N′-ethylenebisketoiminato ligands was synthesized, and one of them was fully characterized by X-ray crystallographic analysis. These cobalt(II) complexes proved to be efficient catalysts in enantioselective borohydride reduction of aryl ke...

Starting from readily available o-phenylenediamines 1, ketones 2 and isocyanides 3, a variety of highly substituted 3,4-dihydroquinoxalin-2-amine derivatives 4 were efficiently synthesized in the presence of catalytic amount of cerium(IV) ammonium nitrate at room temperature. The flexibility of ...

Fluorine is probably another favorite hetero-atom for incorporation into small molecules after nitrogen. Among many fluorine-containing groups, trifluoromethyl aryl ethers (ArOCF3) have unique properties in drug design and are difficult to be synthesized, and many different methods were develope...

We investigated the palladium-catalyzed [2 + 2 + 1] cycloaddition of aryl- and trifluoromethyl-group-substituted internal alkynes and carbon monoxide, and revealed that the PdBr2 effectively catalyzed the intended reaction. The PdBr2-catalyzed reaction smoothly proceeded and provided aryl- and t...

A novel and efficient synthesis of both (±)-methyl epijasmonate and (±)-cis-3-(2-oxopropyl)-2-(pent-2Z-enyl)-cyclopentan-1-one is described. The key step to establish the cis-stereochemistry on the 5-membered ring is an ionic Diels–Alder reaction, which is high yielding and highly regioselect...

This paper describes the selective syntheses of two cis-isomer-enriched cyclopentanone fragrances: (Z)-3-(2-oxopropyl)-2-(pent-2-en-1-yl)cyclopentanone (four steps, 62% overall yield, 67% cis) and Magnolione® (five steps, 60% overall yield, 55% cis). In addition, the asymmetric synthesis of (3aR...

A series of original 2(3H)-benzoxazolone and 2(3H)-benzothiazolone derivatives were evaluated for their affinity at σ1 and σ2 receptor subtypes in competition binding experiments, using [3H](+)-pentazocine or [3H]1,3-di-o-tolyl-guanidine (DTG) in the presence of 100 nM (+)-N-allylnormetazocine...

6-acyl-2(3H)-benzoxazolone and 6-acyl-2(3H)-benzothiazolone derivatives have particularly interesting anti-inflammatory, antiepileptic, analgesic and antiviral properties. In this study, we report an original method of acylation on the 6-position of 2(3H)-benzoxazolone and 2(3H)-benzothiazolone ...

Reduction of esters, amides, and ketones by N,N-diethylaniline borane is accelerated by catalysts derived from spiroborate complexes. Esters are reduced at ambient temperature in less than 4 h with this amine borane and 5 mol % spiroborate 6. Functional group selectivity shows ketone and tertiar...

Both enantiomers of 1,1′-di-tert-butyl-2,2′-dibenzophosphetenyl were prepared from 2-bromobenzyl chloride and tert-butyldichlorophosphine. These ligands exhibited excellent enantioselectivity in the rhodium catalyzed asymmetric hydrogenation of methyl α-acetylamidocinnamate.

Ir-catalysed alkylation of tert-butyl cyanoacetate with a range of substituted benzyl and heteroaryl alcohols under solvent free conditions afforded the corresponding monoalkylated products in moderate to high yields.

A convenient and efficient copper-catalyzed aerobic oxidation of primary amines to aryl nitriles was described. Various benzylic and allylic amines were selectively oxidized to the corresponding nitriles in high yields using CuBr2/NMI as the catalyst and O2 as the oxidant. The oxidation reaction...

Eprosartan mesylate is an angiotensin receptor blocker which suffers from extremely poor bioavailability owing to its poor solubility and poor permeability. The rationale of the present work was to design the drug delivery system capable of overcoming these constraints. Nanoformulation of eprosa...

AimThe present work aim to develop a novel, sensitive and selective HPLC method for the determination of process impurities of Eprosartan mesylate Drug substance (EPM) and characterization of impurities using Mass Spectrometry and NMR.

Quality by design (QbD) principles were implemented to understand the product and process variables of sonoprecipitation technique, for preparation of eprosartan mesylate (EM) nanosuspension. Quality risk management approach was utilized to identify and assess high-risk attributes affecting crit...