Letters in Organic Chemistry - Volume 19, Issue 6, 2022

The regiospecific synthesis of 1H-pyrazole derivatives has been accomplished through the 1,3-dipolar cycloaddition of aryldiazoalkane to but-3-en-2-one. A convenient and inexpensive ultrasound- assisted preparation of cyclopropenes in good yields has been realized. The effect of solvent, ultrasonic power, frequency, reaction time and temperature of cyclopropenation were studied and the order of yield indicates ultrasoun Read More

The phenanthridine family is widely found in medicinal chemistry and material science because of the biological activity and its presence in a variety of significant natural products and synthetic dye stuffs. The phenanthridine has many clinical applications, for e.g., being used as an anticancer agent, possessing antibacterial, antiprotozoal, pharmaceutical, and optoelectronic properties. Many methods have been repo Read More

A convenient synthetic route of deuterium-labeled D5-cyhalothrin, D5-fenpropathrin, and D5-fenvalerate is described with 98.7%, 98.5%, and 98.3% isotopic enrichment and high chemical purities using D6-phenol as labeled starting material. These structures and isotope-abundance were confirmed by 1H NMR and mass spectrometry. The prepared D5-cyhalothrin, D5-fenpropathrin, and D5- fenvalerate can be used as a st Read More

We present a facile and environmentally benign protocol for the synthesis of tetrahydrobenzo[ b]pyran derivatives via multicomponent condensation of dimedon, malononitrile and different aromatic aldehydes in the presence of 1-ethyl-3-methylimidazolium cyanoborohydride ([EMIm][BH3CN]) as catalyst under microwave irradiation. The one-pot synthesis, facile solvent-free condition and good isolated yield illu Read More

An efficient one-pot multicomponent synthesis multicomponent synthesis of 3,4- dihydropyrimidin- 2(1H)-ones has been developed from aldehyde bisulfite adducts, ethyl acetoacetate and urea using recyclable polymer-supported sulfonic acid catalyst. This new method provides several advantages over the previous synthesis, including high product yields, commercially viable, minimal workup operations and sustainable Read More

The manuscript describes a facile and an efficient methodology for the synthesis of 1, 3, 4 trisubstituted-β-lactams by base mediated oxa-Michael addition reactions of 3-hydroxy-2- azetidinones with acetylenic esters under different reaction conditions. These functionalized 1, 3, 4-trisubstituted-azetidin-2-ones are useful organic synthons for the synthesis of various heterocyclic compounds having diverse pharmacological applications.

Esterified and alkyl amine derivatives of mangiferin were synthesized and evaluated for in vitro antioxidant and anticancer activities. The chemical structures of the derivatives were confirmed using elemental analysis and spectral data. The antioxidant activity was assessed using a 2,2-diphenyl-1-picrylhydrazy (DPHH) assay, and some derivatives displayed antioxidant activity better than mangiferin and standard drug ascorbic aci Read More

Photochemical decomposition of lomefloxacin (Lom) is supposed to result in the generation of C-8 substituted impurity and accompanied fluoride. The existence and amount of C-8 hydroxyl substituted Lom could be proposed as the marker to the stability and process consistency. The specific C-8 hydroxyl substituent impurity (1-ethyl-6-fluoro-8-hydroxy-7-(3- methylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid) w Read More

The calix[4]pyrrole is reported as a novel organocatalyst for regioselective ringopening of epoxides under mild reaction conditions. The reaction involves elemental halogen as a nucleophile to afford vicinal halohydrins in good to excellent yield (75-95%). The reactivity of the halide ion in the reaction is governed by different factors, including solvent polarity, temperature and non-covalent interactions of the functional group p Read More

An efficient and eco-friendly approach for the synthesis of β-enaminone derivatives is described by adding nitriles with β-dicarbonyl compounds under ultrasound irradiation conditions at room temperature. The scope and limitation of this strategy are also discussed. A variety of substituted amides can be obtained in moderate to good yields. We hope that this protocol for the efficient synthesis of β-enaminones will offer insig Read More

A set of triethylammonium 4-oxo-6-pyridinethiolate–1,3,4-thiadiazoline hybrids (3a-e) were prepared via the reaction of ethyl 2-chloro-6-cyclopropyl-3- nitro-4-oxothieno[2,3-b]pyridine- 5-carboxylate (2) with the appropriate thiobenzoyl- hydrazide (1a-e) in acetonitrile and triethylamine. These hybrids were readily converted, under neutral mild conditions, into the corresponding 4-hydroxy-6-thioxopyridine –t Read More