Synthesis and Acid–Base Properties of β-Octabromo-Substituted Unsymmetrical Nitrophenylporphyrins

Russian Journal of Organic Chemistry - The bromination of [5-(4-nitrophenyl)-10,15,20-triphenylporphyrinato]cobalt(II) and [5,10,15-tris-(4-nitrophenyl)-20-phenylporphyrinato]cobalt(II) with...     

Synthesis of Unsymmetrical Branched Polyether Dendrons from 3,4-Methylene- dioxybenzaldehyde

Unsymmetrical dendrons 1, 2 and 3 were easily prepared accordins to a novel convergent strategy from 3, 4-methylene-dioxybenzaldehyde as starting material.     

New Synthesis of β-Iodostyrenes

A general procedure for the synthesis of -iodostyrenes is proposed. Aromatic aldehyde and ketone hydrazones are converted into the corresponding -iodostyrenes by treatment with CHI₃ in the presence of a catalytic amount of CuCl.     

Synthesis of β-Sulfoximinopropionic Acids

2-Benzyl-3-(methylsulfoximino)propionic acid has been prepared from 2-benzyl-3-(methylthio)propionamide by cyclization to a isothiazolinone hydrochloride with N-chlorosuccinimide, followed by peracid oxidation and acidic hydrolysis.     

Synthesis of β-Stannyl Esters

A synthesis of β-stannyl esters from ester enolates and iodomethyl (tri-n-butyl) stannane (3) is described.     

Improved Synthesis of Icaritin and Total Synthesis of β-Anhydroicaritin

Natural products icaritin and β-anhydroicaritin with P-glycoprotein(P-gp) inhibitory activities were ciently synthesized in nine steps from commercially available phloroglucinol. A modified Algar-Flynn-Oyamada cyclization and relay Claisen-Cope rearrangement were employed in this concise route. Oiir synthesis offers opportunities to synthesize various icariin analogues for biological and pharmacological investigations.     

Synthesis of β-fluoro-β-proline

A synthetic strategy towards the novel amino acid β-fluoro-β-proline, a fluorinated analogue of β-proline, is elaborated. The synthesis commences from commercially available methyl 2-fluoroacrylate and involves three steps. The overall yield of β-fluoro-β-proline is 57%.     

A Convenient Synthesis of β-Ketosulfoxides

β-Ketosulfoxideshaveattractedmanyorganicchemistsbecauseoftheirwideuseinsynthesisofketones,a-ketols,glyoxals,a-ketoacids,glycols,a-hydroxyacidsandsoculGenerally,6-ketosulfoxidescanbepreparedbythereactionofesterwithsulfoxidel',acylchloridewithsulfoxi...     

Synthesis of β-D-xylopyranoside thiophosphate derivatives

A method of synthesis of β-D-xylopyranoside thiophosphate derivatives was developed. Biological testing revealed a high insecticidal activity in the synthesized compounds.     

Synthesis of monocationic β-cyclodextrin derivatives

Russian Journal of Organic Chemistry - Reactions of 6-bromo- and 6-iodo-6-deoxy-β-cyclodextrin with organic amines of diverse nature afforded a series of monocationic derivatives with aminium...     

Solid Phase Synthesis of β-Carbolines

Much attention has been paid to carbolines in recent years, owing to the wide range of their biological activity 1. Many papers have reported the synthesis and reactivity of carbolines2,3. Generally there are two ways to synthesize carbolines. One is through the Bischler-Napieralski reaction, and the other through Pictet-Spengler reaction. In the former method, the reaction of carboxylic acids with tryptophan using PPE or POCl3 as the condensing agent give dihydro-?-carbolines, which are c…     

Synthesis of β-nitramino derivatives ofgem-dinitroalkanes

A method for the synthesis of β-nitramino derivatives ofgem-dinitroalkanes by nitration of the products of condensation of sulfamic acid derivatives with the correspondinggem-dinitroalkanes was proposed.     

Synthesis and Stereochemistry of some New Unsymmetrical Phosphates with α-Poly-fluoroalkylbenzyl Fragments

Abstract

The methods of synthesis unsymmetrical polyfluoroalkyl phosphates (II) by catalytic phosphorylation of phenols or polyfluoroalkanols by chlorophosphates (I) were elaborated     

Synthesis of a New β-Mercaptoalcohol

Mercaptoalcohols are a rare class of natural products. Some optically active mercaptoalcohols have been used as catalysts in asymmetric reduction of prochiral Ketone1,2. In this letter, we report the synthesis of a new optically active (-mercaptoalcohols, (R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol 7, from L- valine.Our first attempt is showed in Scheme 1. According to literature's method L-valine was converted to (S)-2-Hydroxy-3-methylbutanoic acid 21,2. 2 was treated with MeOH/SOCl2…     

Synthesis based on β-phenylethylamines. IX. Synthesis of sulfides of β-phenylethylamines and of N-benzyltetrahydroisoquinolines

New bimolecular sulfur-containing -phenylethylamines and N-benzyltetrahydroisoquinolines have been synthesized from formyl derivatives of diaryl sulfides. The possibility of using metals as catalysts for obtaining diaryl sulfides in the reaction of ortho-substituted benzaldehydes with SCl₂ has been shown for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–735, September–October, 1995. Original article submitted November 11, 1994.     

Synthesis of Conjugated Polyphenylene Dendritic β-Diketones

An efficient synthesis of high generation conjugated polyphenylene dendrimer-based β-diketones was investi- gated using simple synthetic methods. The new dendrimer-based β-diketones were characterized by NMR, MS and elemental analysis. The UV-Vis and fluorescence spectra of these β-diketones in different solvents were investigated The photoluminescent （PL） quantum yield and TG and DSC curves were also investigated. A new intermediate, 1-bromo-3,5-diiodobenzene, was developed to synthesize high generation dendrimers with good yields.     

Synthesis of a 1,3,4,5-tetrahydrobenzindole β-ketoester

Pd(OAc)₂-catalyzed decomposition of ethyl 2-diazo-4-(4-indolyl)-3-oxobutanoate leads to a tricyclic tetrahydrobenzindole compound formed by a formal C-H insertion reaction. This tricyclic indole rearranges to a novel and thermodynamically more stable naphthalene derivative. Treatment of N-tosyl-protected ethyl 2-diazo-4-(4-indolyl)-3-oxobutanoate with a base induces facile pyrazole formation.     

A Facile Synthesis of β-Cyclodextrin Monoaldehyde

Cyclodextrinsandtheirderivativeshaveplayedimportantrolesinsuchdiversefieldsaschiralseperation,artificalenZymes,asymmetricsynthesisanddrugdelivery'.ThecyclodextrinmonoaldehydeisanewlydevelopedintermediatetosynthesizenovelderivativesthroughreductiveaminationinthepresenseofsodiumcyanoborohydrideThereportedsynthesisofcyclodextrinmonoaldehydeinvolvedtheoxidationofp-CDmonotosylatebyDMSOinthepresenceofcollidineordiisopropylethylamine",ordirectoxidationofP-CDwithDess-Martinperiodinane(DMP)'.Thel…     

Synthesis of new nanocopolymer containing β-lactams

Several new monocyclic β-lactam monomers bearing the NO₂ group 2a–g were synthesized via a [2 + 2] ketene–imine cycloaddition reaction (Staudinger reaction). Calculation of coupling constant of H-3 and H-4, and the X-ray crystallography of β-lactam 2e confirmed the cis stereochemistry of these β-lactams. Then aminophenyl β-lactams were synthesized by the reduction of NO₂ to NH₂ group in the presence of Raney Ni and hydrazine hydrate. Treatment of these aminophenyl β-lactams with acryloyl chloride and sodium bicarbonate (NaHCO₃), afforded the monomers bearing the NHCOCH=CH₂ group. These acrylated β-lactam monomers were dissolved in a warm mixture of butyl acrylate and styrene and then were converted to the corresponding polyacrylate nano β-lactams by emulsion polymerization in water. A unique feature of this methodology is the ability to incorporate water-insoluble compounds directly into the nanoparticle framework. Structures of the synthesized compounds were confirmed by physical and spectral analyses. Dynamic light scattering analysis and transmission electron microscopy of the final emulsions show that the nanoparticles were about 50–70 nm in diameter.     

Synthesis of Isoquinoline Derivatives from β-Hydroxyarylethanamides

A simple and efficient protocol for the construction of medicinally important substituted isoquinolines through intramolecular cyclization of β-hydroxyarylethanamides using acetic anhydride and phosphorous pentoxide in dioxane has been described. The chemo- and regioselectivities due to the influence of different catalysts were investigated and optimized for good to excellent yields. All the synthesized compounds have been characterized by NMR and mass spectral analyses.